KR102635637B1 - Catalyst for Depolymerisation of Polyethylene Terephthalate and Preparing Method of the Same - Google Patents
Catalyst for Depolymerisation of Polyethylene Terephthalate and Preparing Method of the Same Download PDFInfo
- Publication number
- KR102635637B1 KR102635637B1 KR1020210154415A KR20210154415A KR102635637B1 KR 102635637 B1 KR102635637 B1 KR 102635637B1 KR 1020210154415 A KR1020210154415 A KR 1020210154415A KR 20210154415 A KR20210154415 A KR 20210154415A KR 102635637 B1 KR102635637 B1 KR 102635637B1
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- KR
- South Korea
- Prior art keywords
- catalyst
- polyethylene terephthalate
- iron
- reaction
- pet
- Prior art date
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- 229920000139 polyethylene terephthalate Polymers 0.000 title claims abstract description 144
- 239000005020 polyethylene terephthalate Substances 0.000 title claims abstract description 144
- 239000003054 catalyst Substances 0.000 title claims abstract description 140
- -1 Polyethylene Terephthalate Polymers 0.000 title claims abstract description 56
- 238000000034 method Methods 0.000 title description 24
- QPKOBORKPHRBPS-UHFFFAOYSA-N bis(2-hydroxyethyl) terephthalate Chemical compound OCCOC(=O)C1=CC=C(C(=O)OCCO)C=C1 QPKOBORKPHRBPS-UHFFFAOYSA-N 0.000 claims abstract description 75
- 238000012691 depolymerization reaction Methods 0.000 claims abstract description 50
- 238000004519 manufacturing process Methods 0.000 claims abstract description 41
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 94
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- 238000006243 chemical reaction Methods 0.000 claims description 78
- 239000013110 organic ligand Substances 0.000 claims description 41
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 30
- 229910052742 iron Inorganic materials 0.000 claims description 28
- 229910052799 carbon Inorganic materials 0.000 claims description 26
- 229910052751 metal Inorganic materials 0.000 claims description 19
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- 238000003763 carbonization Methods 0.000 claims description 12
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- KKEYFWRCBNTPAC-UHFFFAOYSA-N Terephthalic acid Chemical compound OC(=O)C1=CC=C(C(O)=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-N 0.000 description 9
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- AFCARXCZXQIEQB-UHFFFAOYSA-N N-[3-oxo-3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propyl]-2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidine-5-carboxamide Chemical compound O=C(CCNC(=O)C=1C=NC(=NC=1)NCC1=CC(=CC=C1)OC(F)(F)F)N1CC2=C(CC1)NN=N2 AFCARXCZXQIEQB-UHFFFAOYSA-N 0.000 description 3
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 description 3
- 239000002253 acid Substances 0.000 description 3
- UJMDYLWCYJJYMO-UHFFFAOYSA-N benzene-1,2,3-tricarboxylic acid Chemical compound OC(=O)C1=CC=CC(C(O)=O)=C1C(O)=O UJMDYLWCYJJYMO-UHFFFAOYSA-N 0.000 description 3
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- KKEYFWRCBNTPAC-UHFFFAOYSA-L terephthalate(2-) Chemical compound [O-]C(=O)C1=CC=C(C([O-])=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-L 0.000 description 3
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- 150000003624 transition metals Chemical class 0.000 description 1
- ZIBGPFATKBEMQZ-UHFFFAOYSA-N triethylene glycol Chemical compound OCCOCCOCCO ZIBGPFATKBEMQZ-UHFFFAOYSA-N 0.000 description 1
- 239000013638 trimer Substances 0.000 description 1
- 239000010457 zeolite Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/74—Iron group metals
- B01J23/745—Iron
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/0009—Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
- B01J37/0018—Addition of a binding agent or of material, later completely removed among others as result of heat treatment, leaching or washing,(e.g. forming of pores; protective layer, desintegrating by heat)
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/08—Heat treatment
- B01J37/082—Decomposition and pyrolysis
- B01J37/084—Decomposition of carbon-containing compounds into carbon
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J11/00—Recovery or working-up of waste materials
- C08J11/04—Recovery or working-up of waste materials of polymers
- C08J11/10—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation
- C08J11/16—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation by treatment with inorganic material
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J11/00—Recovery or working-up of waste materials
- C08J11/04—Recovery or working-up of waste materials of polymers
- C08J11/10—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation
- C08J11/18—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation by treatment with organic material
- C08J11/22—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation by treatment with organic material by treatment with organic oxygen-containing compounds
- C08J11/24—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation by treatment with organic material by treatment with organic oxygen-containing compounds containing hydroxyl groups
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2367/00—Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers
- C08J2367/02—Polyesters derived from dicarboxylic acids and dihydroxy compounds
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/62—Plastics recycling; Rubber recycling
Abstract
본 발명은 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매 및 그 제조방법에 관한 것으로, 보다 상세하게는 무색 뿐만 아니라, 안료가 함유된 유색 PET를 원료로 하는 글리콜리시스 해중합 반응에서 있어서 높은 수율로 BHET 생성시킬 수 있는 동시에 내구성이 우수하고, 촉매의 회수 및 재사용이 유리하여 촉매를 반복 재사용하더라도 수율을 그대로 유지할 수 있는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매 및 그 제조방법에 관한 것이다.The present invention relates to a catalyst for the depolymerization reaction of polyethylene terephthalate and a method for producing the same. More specifically, it relates to a catalyst for the depolymerization reaction of polyethylene terephthalate and a method for producing the same. More specifically, it relates to a catalyst for producing BHET in high yield in a glycolysis depolymerization reaction using not only colorless but also colored PET containing pigment as a raw material. The present invention relates to a catalyst for the depolymerization reaction of polyethylene terephthalate, which has excellent durability and is advantageous for recovery and reuse of the catalyst, allowing the yield to be maintained even when the catalyst is repeatedly reused, and a method for producing the same.
Description
본 발명은 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매 및 그 제조방법에 관한 것으로, 보다 상세하게는 폴리에틸렌테레프탈레이트의 글리콜리시스(glycolysis) 해중합 반응에 사용되는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매 및 그 제조방법에 관한 것이다.The present invention relates to a catalyst for the depolymerization reaction of polyethylene terephthalate and a method for producing the same, and more specifically, to a catalyst for the depolymerization reaction of polyethylene terephthalate used in the glycolysis depolymerization reaction of polyethylene terephthalate and a method for producing the same. It's about.
폴리에틸렌테레프탈레이트(polyethyleneterephthalate, 이하 'PET'라 함)는 테레프탈산(TPA) 또는 디메틸테레프탈레이트(DMT)와 에틸렌글리콜(EG)을 주원료하여 에스테르화 반응을 거쳐 축중합 반응을 통해 제조되는 고분자로, 뛰어난 물성, 가공성, 경제성 등을 가지고 있으며, 친환경적이어서 식음료 용기 및 포장재, 의류용 섬유, 필름 및 기타 광범위한 분야에서 쓰이고 있다.Polyethyleneterephthalate (hereinafter referred to as 'PET') is a polymer manufactured through esterification reaction and condensation polymerization reaction using terephthalic acid (TPA) or dimethyl terephthalate (DMT) and ethylene glycol (EG) as main raw materials. It has good physical properties, processability, and economic efficiency, and is eco-friendly, so it is used in food and beverage containers and packaging materials, clothing fibers, films, and a wide range of other fields.
이러한 PET는 일반 합성수지 중에서 가장 폭 넓게 많이 사용되고 있는 만큼 매년 많은 양의 PET 폐기물이 발생하고 있으며, 용이하게 자연 분해되지 않는 특성으로 인해 최근 심각한 환경오염의 주범이 되고 있다. 이에 따라 사용 후 버려지는 음료수 병과 같은 폐 PET 등의 폐기물 재활용이 큰 관심사로 대두되고 있다.As PET is the most widely used among general synthetic resins, a large amount of PET waste is generated every year, and due to its characteristics of not easily decomposing naturally, it has recently become a major cause of serious environmental pollution. Accordingly, recycling waste such as waste PET, such as beverage bottles that are discarded after use, is emerging as a major concern.
폐 PET를 재활용하는 방법에는 크게 물리적 또는 화학적인 방법이 사용되고 있다. 물리적 재활용 방법은 폐 PET를 수집, 세척 및 분쇄하여 재사용하는 것으로, 안료 등을 포함하는 유색 PET에 대해서는 적용하기 어렵고 순도를 보장할 수 없어 널리 응용되지 않고 있으며, 물성이 확보되지 않는 단점이 있다. Physical or chemical methods are largely used to recycle waste PET. The physical recycling method collects, washes, grinds, and reuses waste PET. It is difficult to apply to colored PET containing pigments, etc., and purity cannot be guaranteed, so it is not widely applied and has the disadvantage of not securing physical properties.
한편 화학적 재활용법은 폐 PET 및 올리고머의 오염도와 상관없이 에스테르 결합을 끊는 것으로, 올리고머 회수법인 글리콜리시스(glycolysis)와 모노머 회수법인 메탄올리시스(methanolysis), 가수분해(hydrolysis)로 구분된다. 구체적으로, PET를 화학적으로 재활용하기 위해, 글리콜계 화합물에 의한 글리콜리시스, 메탄올에 의한 메탄올리시스, 물에 의한 가수분해와 같은 분해반응을 통해 PET 고분자 사슬을 분해한 다음 분리정제 과정을 거쳐 BHET, DMT, TPA와 같은 단량체 혹은 폴리에스터 올리고머를 수득하였다. 이렇게 수득된 물질들은 폴리에스터를 합성하는데 사용될 수 있다.Meanwhile, the chemical recycling method breaks the ester bond regardless of the contamination level of waste PET and oligomers, and is divided into glycolysis, which is an oligomer recovery method, and methanolysis and hydrolysis, which are monomer recovery methods. Specifically, in order to chemically recycle PET, the PET polymer chain is decomposed through decomposition reactions such as glycolysis by glycol-based compounds, methanolysis by methanol, and hydrolysis by water, and then goes through a separation and purification process. Monomers such as BHET, DMT, and TPA or polyester oligomers were obtained. The materials thus obtained can be used to synthesize polyester.
특히, 글리콜리시스 해중합 반응은 다른 화학적 리사이클 공정에 비해 낮은 온도와 압력하에 해중합이 이루어지며 처리공정이 단순하다는 장점을 가지고 있다. 이러한 글리콜리시스 해중합 반응은 구체적으로 PET와 에틸렌글리콜(ethyleneglycol, EG)의 반응으로 BHET(bis-hydroxyethyl terephthalate)를 회수하는 방법이다. 가압하에서, 온도범위 180 ℃ 내지 250 ℃사이에서 과량의 글리콜, 보통 EG를 사용하여 BHET 및 올리고머를 생성시키는 것이다. 생성된 BHET는 새로운 PET 고분자 생성에 이용되기 전에 보통 가압하에서 용융여과를 이용하여 촉매나 안료 등을 제거하는 정제 공정을 수행하여야 한다. 상기 해중합은 보통 아연 아세테이트, 리튬 아세테이트와 같은 전이금속 아세테이트 촉매 또는 아연계 촉매 존재하에서 이루어진다. 그러나, 이러한 종래의 촉매는 반응 평형시 BHET의 선택성이 낮고, 촉매의 분리 및 회수가 어렵다는 단점이 있었다. In particular, the glycolysis depolymerization reaction has the advantage of being depolymerized at lower temperature and pressure compared to other chemical recycling processes and the processing process is simple. This glycolysis depolymerization reaction is specifically a method of recovering BHET (bis-hydroxyethyl terephthalate) through the reaction of PET and ethylene glycol (EG). Under pressure, BHET and oligomers are formed using an excess of glycol, usually EG, in the temperature range between 180°C and 250°C. Before the produced BHET can be used to create new PET polymers, it must usually undergo a purification process to remove catalysts or pigments using melt filtration under pressure. The depolymerization is usually carried out in the presence of a transition metal acetate catalyst such as zinc acetate or lithium acetate or a zinc-based catalyst. However, these conventional catalysts had the disadvantage that BHET selectivity was low during reaction equilibrium and separation and recovery of the catalyst were difficult.
이러한 아연 아세테이트 촉매 등의 균일계 촉매는 반응속도가 빠르고 BHET를 잘 생성하나 BHET 모노머가 Dimer 또는 Trimer로 중합되고, 이것이 다시 분해과정을 거쳐 반응 평형상태에 도달하게 되며, 이렇게 반응평형 상태에 도달되었을 때 BHET의 수율이 90 % 정도, Dimer의 수율이 10 % 정도 된다. 특히 반응 평형상태에서 BHET의 수율은 반응 조건 즉, PET/EG ratio에 따라 달라지게 되며 EG를 과량 사용할수록 반응 평형상태에서 BHET의 수율이 향상된다. 이렇듯 균일계 촉매는 반응 평형시 BHET의 선택성이 낮다는 단점이 있었다. 또 다른 단점으로는 촉매의 분리 및 회수가 어렵다는 것으로, 균일계 촉매상 활성성분을 모두 회수하려면 상당히 많은 에너지가 소모되는 증류 공정을 진행해야 하고, 또한 일부 금속 성분이 남아 있다면 최종 생성물(BHET)에도 남아 있기 때문에 이를 이용하여 음용 용기 목적의 PET 제조에 사용되는 것에는 한계가 있었다.Homogeneous catalysts such as zinc acetate catalysts have a fast reaction rate and produce BHET well, but the BHET monomer is polymerized into Dimer or Trimer, which goes through a decomposition process again to reach a reaction equilibrium state. At this time, the yield of BHET is about 90% and the yield of Dimer is about 10%. In particular, the yield of BHET in the reaction equilibrium state varies depending on the reaction conditions, that is, the PET/EG ratio, and the more EG is used, the better the yield of BHET in the reaction equilibrium state. As such, the homogeneous catalyst had the disadvantage of low BHET selectivity during reaction equilibrium. Another disadvantage is that it is difficult to separate and recover the catalyst. In order to recover all the active ingredients from the homogeneous catalyst, a distillation process that consumes quite a lot of energy must be performed, and if some metal components remain, they are also stored in the final product (BHET). Because it remained, there were limits to its use in manufacturing PET for drinking containers.
이에 한국공개특허 제2021-0067749호에서는 높은 수율로 BHET를 수득하기 위해 폐 PET의 글리콜리시스 해중합 반응에 섬유상 페로브스카이트 촉매를 이용하는 폐 PET의 재활용 방법이 개시된 바 있으나, 상기 선행기술의 촉매와 같은 불균일계 촉매를 적용하더라도, 해중합 반응에서 생성된 해중합물의 경우 분자량이 높아 촉매 잔류 없이 촉매 분리 및 회수가 어렵고, 재사용시에는 촉매활성 성분의 침출이 발생되어 순도가 높은 BHET을 수득할 수 없는 문제점이 있었다. Accordingly, in Korea Patent Publication No. 2021-0067749, a method for recycling waste PET using a fibrous perovskite catalyst in the glycolysis depolymerization reaction of waste PET to obtain BHET in high yield has been disclosed, but the catalyst of the prior art Even if a heterogeneous catalyst such as the following is applied, the molecular weight of the depolymerized product produced in the depolymerization reaction is high, so it is difficult to separate and recover the catalyst without catalyst residue, and when reused, leaching of catalytically active components occurs, making it impossible to obtain high-purity BHET. There was a problem.
또한, 한국공개특허 제2021-0066354호에서는 유색 PET의 해중합 과정 중에 안료를 제거하기 위해 해중합 과정 전, 후 및 중간에 테프론 수지를 이용하여 안료를 흡착 제거한 후 BHET를 생성하는 방법이 개시된 바 있으나, 상기 선행기술 또한, 유색 PET로부터 안료를 제거하기 위해 해중합 과정 전, 후 및 중간에 여러 차례의 안료 정제 과정을 수행해야 하는 등의 문제점이 있었다. In addition, Korean Patent Publication No. 2021-0066354 discloses a method of generating BHET after adsorbing and removing pigments using Teflon resin before, after, and during the depolymerization process to remove pigments during the depolymerization process of colored PET. The above prior art also had problems such as having to perform several pigment purification processes before, after, and during the depolymerization process to remove pigments from colored PET.
이에 따라, 여러번의 정제 과정을 거치지 않고, PET의 글리콜리시스 해중합 방법으로 고순도의 BHET를 높은 수율로 수득하는 동시에 사용 후 해중합용 촉매를 안정적으로 재사용할 수 있는 기술 개발이 필요한 실정이다. Accordingly, there is a need to develop a technology that can obtain high purity BHET in high yield through the glycolysis depolymerization method of PET without going through multiple purification processes and at the same time stably reuse the depolymerization catalyst after use.
본 발명의 하나의 목적은 PET의 글리콜리시스 해중합 반응에서 높은 수율로 BHET를 생성시킬 수 있는 동시에 내구성이 우수하고, 촉매의 회수 및 재사용이 유리하여 촉매를 반복 재사용하더라도 BHET의 수율을 그대로 유지할 수 있는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매 및 그 제조방법을 제공하는데 있다. One purpose of the present invention is to produce BHET in high yield in the glycolysis depolymerization reaction of PET, and at the same time have excellent durability, and the recovery and reuse of the catalyst is advantageous, so that the yield of BHET can be maintained even if the catalyst is repeatedly reused. The aim is to provide a catalyst for the depolymerization reaction of polyethylene terephthalate and a method for producing the same.
본 발명의 다른 목적은 안료가 함유된 유색 PET의 글리콜리시스 해중합 반응에 있어서, 안료의 제거와 동시에 고수율로 BHET을 수득할 수 있는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매 및 그 제조방법을 제공하는데 있다. Another object of the present invention is to provide a catalyst for the depolymerization of polyethylene terephthalate and a method for producing the same, which can obtain BHET in high yield while removing the pigment in the glycolysis depolymerization of colored PET containing pigment. there is.
본 발명의 또 다른 목적은, 상기의 촉매를 이용하여 PET의 글리콜리시스 해중합 반응으로 BHET를 제조하는 방법을 제공하는데 있다.Another object of the present invention is to provide a method for producing BHET through glycolysis depolymerization of PET using the above catalyst.
상기와 같은 목적을 달성하기 위하여, 본 발명의 일 구현예는, 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매에 있어서, 상기 촉매는 촉매활성 성분인 철이 탄소체에 의해 둘러싸여 있는 것을 특징으로 하는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매를 제공한다. In order to achieve the above object, one embodiment of the present invention is a catalyst for the depolymerization reaction of polyethylene terephthalate, wherein iron, a catalytically active component, is surrounded by a carbon body. A catalyst for depolymerization reaction is provided.
본 발명의 바람직한 일 구현예에서, 상기 촉매는 철-유기리간드 골격체를 탄화시켜 형성된 것을 특징으로 할 수 있다.In a preferred embodiment of the present invention, the catalyst may be formed by carbonizing an iron-organic ligand skeleton.
본 발명의 바람직한 일 구현예에서, 상기 철-유기리간드 골격체는 철(Fe)이 중심금속으로 된 Fe계 MOF인 것을 특징으로 할 수 있다. In a preferred embodiment of the present invention, the iron-organic ligand framework may be characterized as an Fe-based MOF with iron (Fe) as the central metal.
본 발명의 바람직한 일 구현예에서, 상기 폴리에틸렌테레프탈레이트의 해중합 반응은 폴리에틸렌테레프탈레이트와 글리콜과의 반응인 것을 특징으로 할 수 있다.In a preferred embodiment of the present invention, the depolymerization reaction of polyethylene terephthalate may be characterized as a reaction between polyethylene terephthalate and glycol.
본 발명의 다른 구현예는, 철-유기리간드 골격체를 불활성 분위기에서 탄화시켜 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매를 제조하는 단계를 포함하고, 상기 제조된 촉매는 촉매활성 성분인 철이 탄소체에 의해 둘러싸여 있는 것을 특징으로 하는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매의 제조방법을 제공한다.Another embodiment of the present invention includes preparing a catalyst for depolymerization of polyethylene terephthalate by carbonizing an iron-organic ligand skeleton in an inert atmosphere, wherein iron, a catalytically active component, is formed by carbonization. A method for producing a catalyst for depolymerization reaction of polyethylene terephthalate is provided, which is characterized in that the catalyst is surrounded.
본 발명의 바람직한 다른 구현예에서, 상기 철-유기리간드 골격체는 철(Fe)이 중심금속으로 된 Fe계 MOF인 것을 특징으로 할 수 있다. In another preferred embodiment of the present invention, the iron-organic ligand framework may be characterized as an Fe-based MOF with iron (Fe) as the central metal.
본 발명의 바람직한 다른 구현예에서, 상기 철-유기리간드 골격체는 유기용매상에 철 전구체 및 유기리간드 화합물을 1 : 0.5 ~ 3.0 몰비로 혼합한 후, 반응시켜 수득하는 것을 특징으로 할 수 있다.In another preferred embodiment of the present invention, the iron-organic ligand framework may be obtained by mixing an iron precursor and an organic ligand compound in an organic solvent at a molar ratio of 1:0.5 to 3.0 and then reacting.
본 발명의 바람직한 다른 구현예에서, 상기 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매의 제조방법은 철-유기리간드 골격체의 탄소화 전에 철-유기리간드 골격체에 탄소 전구체를 더 포함하여 탄소화를 수행하는 것을 특징으로 할 수 있다. In another preferred embodiment of the present invention, the method for producing a catalyst for the depolymerization reaction of polyethylene terephthalate further includes a carbon precursor in the iron-organic ligand framework before carbonization of the iron-organic ligand framework to perform carbonization. It can be characterized as:
본 발명의 바람직한 다른 구현예에서, 상기 상기 탄소 전구체는 퍼퓨릴알코올(furfuryl alcohol), 다이비닐벤젠(divinylbenzene), 우레아(urea), 글루코스(glucose), 수크로스 에틸렌글리콜(sucrose etylene glycol), 글리세롤(glycerol), 자일리톨(xylitol) 및 멜라민(melamine)으로 구성된 군에서 선택되는 1종 이상인 것을 특징으로 할 수 있다.In another preferred embodiment of the present invention, the carbon precursor is furfuryl alcohol, divinylbenzene, urea, glucose, sucrose etylene glycol, and glycerol. It may be characterized as being one or more types selected from the group consisting of (glycerol), xylitol, and melamine.
본 발명의 바람직한 다른 구현예에서, 상기 탄화는 600 ℃ ~ 1200 ℃에서 수행하는 것을 특징으로 할 수 있다. In another preferred embodiment of the present invention, the carbonization may be performed at 600°C to 1200°C.
본 발명의 또 다른 구현예는, 상기의 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매 존재하에서 폴리에틸렌테레프탈레이트와 글리콜과의 반응으로 BHET를 제조하는 것을 특징으로 하는 BHET의 제조방법을 제공한다. Another embodiment of the present invention provides a method for producing BHET, characterized in that BHET is produced by reacting polyethylene terephthalate with glycol in the presence of a catalyst for the depolymerization reaction of polyethylene terephthalate.
본 발명의 바람직한 또 다른 구현예에서, 상기 글리콜은 폴리에틸렌테레프탈레이트 100 중량부에 대하여, 100 중량부 내지 3000 중량부인 것을 특징으로 할 수 있다.In another preferred embodiment of the present invention, the glycol may be present in an amount of 100 to 3000 parts by weight based on 100 parts by weight of polyethylene terephthalate.
본 발명에 따른 촉매는 높은 촉매활성으로 PET의 글리콜리시스 해중합 반응을 촉진시킴으로써 높은 전환율과 수율로 BHET를 제조할 수 있는 동시에, 촉매 활성물질인 철이 탄소체에 의해 둘러싸여 있어 촉매 활성물질이 침출되거나 소실되지 않을 뿐만 아니라, 촉매 자체가 자성을 나타냄에 따라 자석을 이용하여 반응 생성물로부터 촉매를 용이하게 분리 및 회수를 할 수 있고, 촉매 재사용시에도 촉매 활성을 유지할 수 있는 효과가 있다.The catalyst according to the present invention can produce BHET with high conversion and yield by promoting the glycolysis depolymerization reaction of PET with high catalytic activity. At the same time, iron, which is a catalytically active material, is surrounded by a carbon body, so the catalytically active material is not leached or Not only is it not lost, but since the catalyst itself is magnetic, the catalyst can be easily separated and recovered from the reaction product using a magnet, and the catalyst activity can be maintained even when the catalyst is reused.
또한, 본 발명에 따른 촉매는 탄소체를 포함함으로써, 안료의 제거와 동시에 고수율로 BHET을 수득할 수 있어 PET 원료를 분류하고 선별하는 추가적이 전 단계 공정이나, 안료를 제거하기 위한 정제 단계 공정을 생략할 수 있어 산업적으로 매우 유용하게 사용할 수 있다.In addition, since the catalyst according to the present invention contains a carbon body, BHET can be obtained in high yield at the same time as the pigment is removed, so it is necessary to perform an additional pre-stage process of classifying and selecting PET raw materials or a purification step to remove the pigment. can be omitted, making it very useful industrially.
도 1은 본 발명의 제조예 1에서 제조된 촉매 및 철-유기리간드 골격체의 SEM 사진 및 TEM 사진으로, (a)는 철-유기리간드 골격체의 SEM 사진이고, (b)는 제조예 1에서 제조된 촉매의 SEM 사진이며, (c)는 제조예 1에서 제조된 촉매의 TEM 사진이고, (d)는 (c)의 확대 TEM이다.
도 2는 본 발명에 따른 촉매의 반응 반복 수행에 대한 촉매의 XRD 측정 그래프이다.Figure 1 is an SEM photograph and a TEM photograph of the catalyst and iron-organic ligand framework prepared in Preparation Example 1 of the present invention, (a) is an SEM photograph of the iron-organic ligand framework, and (b) is Preparation Example 1. (c) is a TEM image of the catalyst prepared in Preparation Example 1, and (d) is an enlarged TEM of (c).
Figure 2 is a graph of the XRD measurement of the catalyst for repeated reactions of the catalyst according to the present invention.
다른 식으로 정의되지 않는 한, 본 명세서에서 사용된 모든 기술적 및 과학적 용어들은 본 발명이 속하는 기술분야에서 숙련된 전문가에 의해서 통상적으로 이해되는 것과 동일한 의미를 가진다. 일반적으로, 본 명세서에서 사용된 명명법 은 본 기술분야에서 잘 알려져 있고 통상적으로 사용되는 것이다.Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by a person skilled in the art to which the present invention pertains. In general, the nomenclature used herein is well known and commonly used in the art.
본 명세서에 기재된 '구비한다', '함유한다', '포함한다' 또는 '가진다' 등의 용어는 명세서상에 기재된 특징, 수치, 단계, 동작, 구성요소, 부품 또는 이들의 조합이 존재함을 지칭하는 것이고, 언급되지 않은 다른 특징, 수치, 단계, 동작, 구성요소, 부품 또는 이들의 조합이 존재하거나 부가될 수 있는 가능성을 배제하지 않는다.Terms such as 'comprises', 'contains', 'includes', or 'has' used in the specification indicate the presence of features, values, steps, operations, components, parts, or combinations thereof described in the specification. It refers to, and does not exclude the possibility that other features, values, steps, operations, components, parts, or combinations thereof not mentioned may exist or be added.
이하, 본 발명의 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매 및 이의 제조방법을 보다 상세하게 설명한다.Hereinafter, the catalyst for the depolymerization reaction of polyethylene terephthalate of the present invention and its preparation method will be described in more detail.
본 발명의 발명자들은 금속유기골격체의 중심금속으로 철이 함유된 철-유기리간드 골격체를 탄화시켜 얻어진 촉매가 종래 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매에 비해 고수율로 BHET(bis-hydroxyethyl terephthalate)를 수득할 수 있는 동시에 내구성이 우수하여 촉매 활성물질이 침출되거나 소실되지 않고, 반응 후 사용된 촉매를 반응 생성물로부터 용이하게 분리 및 회수할 수 있으며, 촉매 재사용시에도 촉매 활성을 그대로 유지할 수 있음을 확인하고, 본 발명을 완성하였다.The inventors of the present invention believe that the catalyst obtained by carbonizing the iron-organic ligand framework containing iron as the central metal of the metal-organic framework produces BHET (bis-hydroxyethyl terephthalate) in higher yield than the conventional catalyst for the depolymerization reaction of polyethylene terephthalate. It was confirmed that the catalytic active material does not leach or disappear due to excellent durability, the catalyst used after the reaction can be easily separated and recovered from the reaction product, and the catalytic activity can be maintained even when the catalyst is reused. And the present invention was completed.
또한, 본 발명에 따른 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매는 안료가 함유된 유색 PET의 글리콜리시스 해중합 반응에 있어서도, 안료 제거와 동시에 높은 수율로 BHET을 수득할 수 있음을 확인할 수 있었다.In addition, it was confirmed that the catalyst for the depolymerization reaction of polyethylene terephthalate according to the present invention can obtain BHET in high yield simultaneously with the removal of the pigment even in the glycolysis depolymerization reaction of colored PET containing pigment.
본 발명에 따른 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매는 촉매활성 성분인 철이 탄소체에 의해 둘러싸여 있는 것을 특징으로 한다.The catalyst for the depolymerization reaction of polyethylene terephthalate according to the present invention is characterized in that iron, a catalytically active component, is surrounded by a carbon body.
상기 탄소체의 바람직한 일 실시예로서, 상기 탄소체는 금속유기골격체를 고온에서 열처리하여 제조된 탄소체를 들 수 있다. As a preferred example of the carbon body, the carbon body may be a carbon body manufactured by heat-treating a metal-organic framework at high temperature.
상기 금속유기골격체(MOF)는 금속 또는 금속-유기 클러스터(cluster)가 유기 리간드(organic linker)와 배위결합으로 연결되어 골격을 형성하고 있는 하이브리드 물질이며, 금속-유기 클러스터는 골격에서 노드(node)가 될수 있다. 따라서 MOF 는 분자크기 또는 나노크기의 세공구조를 갖는 결정성 화합물로서, '유무기 하이브리드 나노세공체' 또는 '다공성 배위고분자(porous coordination polymers)'라고도 한다. The metal-organic framework (MOF) is a hybrid material in which a metal or metal-organic cluster is linked to an organic ligand (organic linker) through coordination bonds to form a framework, and the metal-organic cluster is a node in the framework. ) can be. Therefore, MOF is a crystalline compound with a molecular or nano-sized pore structure, and is also called 'organic-inorganic hybrid nanoporous material' or 'porous coordination polymers'.
상기 금속유기골격체(MOF)는 기본적으로 제올라이트와 비슷한 물성을 지니는 다공성 물질이며, 용매열 합성법(solvothermal synthesis), 마이크로파 및 초음파합성법, 기계적 마찰을 이용한 합성, 그리고 이온성 액체를 합성 용매로 이용하는 이온열(ionothermal) 합성법 등으로 용이하게 제조할 있고, 일 예로, 상기 용매열 합성법(solvothermal synthesis)은 전이금속 전구체와 유기리간드 및 유기용매를 용기에 넣고 밀봉한 다음, 가열하여 금속유기골격체(MOF)를 용이하게 제조할 수 있다.The metal organic framework (MOF) is basically a porous material with similar physical properties to zeolite, and is synthesized using solvothermal synthesis, microwave and ultrasonic synthesis, mechanical friction, and ionic liquid as a synthesis solvent. It can be easily manufactured by ionothermal synthesis. For example, the solvothermal synthesis method involves placing a transition metal precursor, an organic ligand, and an organic solvent in a container, sealing it, and then heating to form a metal-organic framework (MOF). ) can be easily manufactured.
또한, 금속유기골격체(MOF)는 중심금속-유기리간드의 성분을 변경함으로써, 촉매의 활성이나, 기공의 크기 및 윈도우의 직경을 조절하는 것이 가능하다. 구체적으로, 금속유기골격체는 중심금속을 폴리에틸렌테레프탈레이트의 해중합 반응에 있어서 촉매활성 성분으로 변경할 경우에는 추가적인 촉매활성 성분의 담지나 함침 없이 촉매활성 성분이 유기리간드 골격 내부에 고정된 촉매를 제조할 수 있다.In addition, the metal-organic framework (MOF) can control the catalytic activity, pore size, and window diameter by changing the components of the central metal-organic ligand. Specifically, when the metal-organic framework changes the central metal to a catalytically active component in the depolymerization reaction of polyethylene terephthalate, a catalyst in which the catalytically active component is fixed inside the organic ligand framework can be manufactured without supporting or impregnating additional catalytically active components. You can.
이에, 본 발명에서는 전술된 금속유기골격체(MOF) 특징을 이용하여 금속유기골격체(MOF)의 중심금속으로 폴리에틸렌테레프탈레이트의 글리콜리시스 해중합 반응에 높은 활성을 나타내는 동시에, 자성을 나타내는 철을 촉매활성 성분으로 하여 유기리간드에 고정시켜 탄화시킴으로써, 금속유기골격체 내의 골격을 이루는 유기리간드의 탄소-탄소 결합이 깨지고, 새로운 탄소-탄소 결합이 생성되면서 탄소체가 중심금속인 철을 둘러싸는 형태로 생성되어 촉매활성 성분인 철이 탄소체에 의해 둘러싸인 형태의 촉매를 수득할 수 있었다. Accordingly, in the present invention, using the above-described characteristics of the metal-organic framework (MOF), iron, which exhibits high activity in the glycolysis depolymerization reaction of polyethylene terephthalate and is also magnetic, is used as the central metal of the metal-organic framework (MOF). By carbonizing the organic ligand by fixing it as a catalytically active ingredient, the carbon-carbon bond of the organic ligand forming the skeleton within the metal-organic framework is broken, and a new carbon-carbon bond is created, forming a carbon body that surrounds iron, the central metal. It was possible to obtain a catalyst in which iron, a catalytically active component, was surrounded by a carbon body.
이와 같은 촉매는 금속유기골격체 내부 공간에 촉매활성 성분인 철이 물리적 화학적으로 캡슐화되어 반응 중 침출되거나 소실되지 않을 뿐만 아니라, 촉매활성 성분인 철이 촉매 골격을 이루는 유기리간드와 화학적 결합을 이룸으로써, 발생할 수 있는 촉매활성이 저하되는 문제점을 방지할 수 있고, 해중합 반응에서 생성된 해중합물의 경우 분자량이 높아 촉매가 분리가 어려운 경우에도 자석을 이용하여 촉매 분리 및 회수가 용이하다.In this type of catalyst, iron, a catalytically active component, is physically and chemically encapsulated in the internal space of the metal-organic framework, so that it is not leached or lost during the reaction, and the iron, a catalytically active component, forms a chemical bond with the organic ligand that forms the catalyst skeleton, thereby reducing the generation of iron. It is possible to prevent the problem of a possible decrease in catalytic activity, and in the case of the depolymerized product produced in the depolymerization reaction, it is easy to separate and recover the catalyst using a magnet even when the molecular weight is high and the catalyst is difficult to separate.
이와 같은 철이 중심금속으로 포함된 금속유기골격체(이하, 철-유기리간드 골격체라 함)는 비제한적 예시로서, PCN-250, PCN-600, Fe-MOF-74, MIL53, MIL-88, MIL-89, MIL-96, MIL-100, MIL-101, MIL-102, MIL-126, MIL-127 및 이의 기능화된 MOF 중에서 선택되는 하나 이상을 사용할 수 있다. Such metal-organic frameworks containing iron as a central metal (hereinafter referred to as iron-organic ligand frameworks) are non-limiting examples, such as PCN-250, PCN-600, Fe-MOF-74, MIL53, MIL-88, and MIL. One or more selected from -89, MIL-96, MIL-100, MIL-101, MIL-102, MIL-126, MIL-127, and functionalized MOFs thereof may be used.
또한, 상기 철-유기리간드 골격체는 철이 중심금속으로 포함된 금속유기골격체를 제조할 수 있는 방법이면 제한 없이 적용 가능하고, 바람직하게는 유기용매상에 철 전구체와 유기리간드 화합물을 혼합하고, 반응시켜 철-유기리간드 골격체를 제조할 수 있다. 이때, 상기 철 전구체와 유기리간드 화합물은 1 : 0.5 ~ 3.0 몰비로 혼합할 수 있다.In addition, the iron-organic ligand framework can be applied without limitation as long as it can produce a metal-organic framework containing iron as a central metal. Preferably, the iron precursor and the organic ligand compound are mixed in an organic solvent, The iron-organic ligand framework can be produced through reaction. At this time, the iron precursor and the organic ligand compound can be mixed at a molar ratio of 1:0.5 to 3.0.
상기 철 전구체는 철 이온을 포함하는 유기 화합물 및 무기 화합물을 포함하는 군에서 선택된 하나 이상일 수 있으며, 구체적으로 철의 염화물, 황화물, 질화물, 수화물, 금속 철 분말 등일 수 있다.The iron precursor may be one or more selected from the group including organic compounds and inorganic compounds containing iron ions, and may specifically be iron chloride, sulfide, nitride, hydrate, metallic iron powder, etc.
또한, 상기 금속유기골격체의 유기리간드 화합물은 링커(linker)라고도 하며, 배위할 수 있는 작용기를 가진 어떠한 유기 화합물도 가능하고, 배위할 수 있는 작용기는 카르복실산기, 카르복실산 음이온기, 아미노기(-NH2), 이미노기(-NH), 아미드기(-CONH2), 술폰산기(-SO3H), 술폰산 음이온기(-SO3-), 메탄디티오산기(-CS2H), 메탄디티오산 음이온기(-CS2-), 피리딘기 또는 피라진기 등이 예시될 수 있다. 보다 안정한 유무기혼성체를 유도하기 위해서는 배위할 수 있는 자리가 2개 이상인, 예를 들면 바이덴테이트 또는 트리덴테이트인 유기 화합물이 유리하다. 유기 화합물로는 배위할 자리가 있다면 비피리딘, 피라진 등의 중성 유기 화합물, 테레프탈레이트, 나프탈렌디카복실레이트, 벤젠트리카복실레이트, 글루타레이트, 숙신네이트 등으로 예시될 수 있는 카본산의 음이온 등의 음이온성 유기 화합물은 물론 양이온 물질도 가능하다. In addition, the organic ligand compound of the metal-organic framework is also called a linker, and can be any organic compound with a functional group that can coordinate, and the functional group that can coordinate is a carboxylic acid group, carboxylic acid anion group, and amino group. (-NH 2 ), imino group (-NH), amide group (-CONH 2 ), sulfonic acid group (-SO 3 H), sulfonic acid anion group (-SO 3 -), methanedithioic acid group (-CS 2 H) , methanedithioic acid anionic group (-CS 2 -), pyridine group, or pyrazine group, etc. may be exemplified. In order to induce a more stable organic-inorganic hybrid, an organic compound having two or more coordination sites, for example, bidentate or tridentate, is advantageous. Organic compounds include neutral organic compounds such as bipyridine and pyrazine, if there is a site for coordination, and anions of carboxylic acids such as terephthalate, naphthalene dicarboxylate, benzene tricarboxylate, glutarate, and succinate. Anionic organic compounds as well as cationic substances are possible.
상기 카본산음이온의 경우 예를 들면 테레프탈레이트 같은 방향족 링을 갖는 것 외에 포르메이트 같은 선형의 카본산의 음이온은 물론이고 시클로헥실디카보네이트와 같이 비방향족 링을 갖는 음이온 등 어느 것이라도 가능하다. 배위할 수 있는 자리를 가진 유기 화합물은 물론 잠재적으로 배위할 자리를 갖고 있어 반응 조건에서 배위할 수 있게 변환되는 유기 화합물도 사용 가능하다. 즉, 테레프탈산 같은 유기산을 사용하여도 반응 후에는 테레프탈레이트로 금속 성분과 결합할 수 있다. 사용할 수 있는 유기 화합물의 대표적인 예로는 벤젠디카르복실산, 나프탈렌디카복실산, 벤젠트리카복실산, 나프탈렌트리카복실산, 피리딘디카복실산, 비피리딜디카복실산, 포름산, 옥살산, 말론산, 숙신산, 글루타르산, 헥산다이오익산, 헵탄다이오익산, 또는 시클로헥실디카복실산에서 선택되는 유기산 및 그들의 음이온, 피라진, 비피리딘 등이다. 또한, 하나 이상의 유기 화합물을 혼합하여 사용할 수도 있다.In the case of the carboxylic acid anion, for example, in addition to having an aromatic ring such as terephthalate, any anion such as an anion of a linear carboxylic acid such as formate or an anion having a non-aromatic ring such as cyclohexyl dicarbonate is possible. Organic compounds that have a site for coordination can be used, as well as organic compounds that have a potential site for coordination and are converted to coordinate under reaction conditions. In other words, even if an organic acid such as terephthalic acid is used, it can combine with the metal component as terephthalate after the reaction. Representative examples of organic compounds that can be used include benzenedicarboxylic acid, naphthalenedicarboxylic acid, benzenetricarboxylic acid, naphthalenetricarboxylic acid, pyridinedicarboxylic acid, bipyridyldicarboxylic acid, formic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, and hexane. Organic acids selected from dioic acid, heptanedioic acid, or cyclohexyldicarboxylic acid and their anions, pyrazine, bipyridine, etc. Additionally, one or more organic compounds may be mixed and used.
한편, 상기 철 전구체와 유기리간드 화합물 외에 금속유기골격체의 합성에 사용되는 유기용매는 물, 메탄올, 에탄올, 프로판올 등의 알콜류, 아세톤, 메틸에틸케톤 등의 케톤 류, 헥산, 헵탄, 옥탄 등의 탄화수소류 등 어떠한 물질도 사용가능하며 두 가지 이상의 용매를 섞어 사용할 수도 있으며 물이 가장 적합하다.Meanwhile, in addition to the iron precursor and organic ligand compounds, organic solvents used in the synthesis of metal-organic frameworks include water, alcohols such as methanol, ethanol, and propanol, ketones such as acetone and methyl ethyl ketone, and hexane, heptane, and octane. Any substance, including hydrocarbons, can be used, and two or more solvents can be mixed, with water being the most suitable.
상기 금속유기골격체의 합성을 위한 철 전구체와 유기리간드 화합물의 반응은 실제적으로 제한되지 않으나, 100 ℃ ~ 300 ℃일 수 있으며, 바람직하게는 100 ℃ ~ 250 ℃온도가 바람직하다. 반응 온도가 너무 낮으면 반응 속도가 느려 효과적이지 못하고, 반응 온도가 너무 높으면 세공이 없는 물질이 얻어지기 쉬우며, 반응 속도가 너무 빨라 불순물이 혼입되기 쉽고, 반응기 내부 압력이 높아져 반응기의 구성이 비경제적이다.The reaction between the iron precursor and the organic ligand compound for the synthesis of the metal-organic framework is not practically limited, but may be at a temperature of 100°C to 300°C, and is preferably 100°C to 250°C. If the reaction temperature is too low, the reaction speed is slow and ineffective, and if the reaction temperature is too high, a material without pores is likely to be obtained. If the reaction speed is too fast, impurities are likely to be mixed in, and the internal pressure of the reactor increases, resulting in an irregular composition of the reactor. It's economical.
이와 같은 상기 철-유기리간드 골격체는 탄화시킴으로써, 철-유기리간드 골격체내 유기 클러스터 혹은 유기리간드의 탄소-탄소 결합이 생성되어 육방정계의 결정 구조를 가지는 탄소체가 철-유기리간드 골격체의 중심금속인 철을 에워싼 형태로 생성시킬 수 있다. By carbonizing the iron-organic ligand framework, organic clusters within the iron-organic ligand framework or carbon-carbon bonds of the organic ligands are created, and the carbon body with a hexagonal crystal structure becomes the central metal of the iron-organic ligand framework. It can be created in a form that surrounds phosphorus iron.
이때, 상기 탄화는 600 ℃ ~ 1200 ℃에서 1 ~ 6 시간동안 수행할 수 있고, 탄화 분위기는 헬륨, 질소, 아르곤 또는 금속 환원을 위해 수소가 일부 섞인 비활성 기체 하에서 실시하는 것이 바람직하다.At this time, the carbonization can be performed at 600 ° C to 1200 ° C for 1 to 6 hours, and the carbonization atmosphere is preferably helium, nitrogen, argon, or an inert gas mixed with some hydrogen for metal reduction.
상기 탄화 온도가 600 ℃ 또는 1 시간 미만일 경우, 탄소체로의 전환이 발생하지 않고 MOF의 일부 구조가 깨지거나, 단지 건조 상태가 되는 상태에 머무르게 될 수 있으며, 1200 ℃ 또는 6 시간을 초과할 경우에는 금속의 고용체 반응으로 인해 철의 분산도가 크게 저하될 수 있고, 철이 탄소체 밖으로 이동 및 표면적이 급격히 감소하는 문제점이 발생될 수 있다.If the carbonization temperature is less than 600°C or 1 hour, conversion to the carbon body does not occur and some structures of the MOF may be broken or may remain in a dry state, and if it exceeds 1200°C or 6 hours, the carbonization temperature may not occur. Due to the solid solution reaction of the metal, the dispersion of iron may be greatly reduced, and problems may occur in which iron moves out of the carbon body and the surface area rapidly decreases.
이와 같은 본 발명에 따른 촉매는 중심금속으로 철이 포함된 금속유기골격체를 고온에서 탄화시켜 촉매활성 성분인 철이 탄소체로 둘러싸인 형태로 제조됨으로써, 촉매활성 성분의 침출이나 소실을 방지할 수 있고, 반응원료로 안료가 함유된 유색 PET를 사용한 경우에는 안료를 흡착시켜 제거하는 역할 또한 수행할 수 있어 PET 원료를 분류하고 선별하는 추가적이 전 단계 공정이나, 안료를 제거하기 위한 정제 단계 공정을 생략할 수 있고, 유색 PET로부터 무색 BHET를 제조할 수 있다. The catalyst according to the present invention is produced by carbonizing a metal-organic framework containing iron as a central metal at high temperature so that iron, a catalytically active component, is surrounded by a carbon body, thereby preventing leaching or loss of the catalytically active component and reaction. If colored PET containing pigment is used as a raw material, it can also serve to adsorb and remove the pigment, so the additional pre-process of classifying and selecting PET raw materials or the purification step to remove the pigment can be omitted. And colorless BHET can be manufactured from colored PET.
한편 본 발명에 따른 촉매는 탄소체 함량을 증가시켜 촉매의 비표면적과 흡착력을 증가시키기 위해 탄화 단계 이전에 철-유기리간드 골격체에 탄소 전구체를 더 첨가시켜 탄화시킬 수 있다. Meanwhile, the catalyst according to the present invention can be carbonized by adding a carbon precursor to the iron-organic ligand skeleton before the carbonization step in order to increase the specific surface area and adsorption power of the catalyst by increasing the carbon content.
이때, 상기 탄소 전구체는 철-유기리간드 골격체 100 중량부에 대하여, 50 중량부 미만을 첨가할 수 있다. 상기 탄소 전구체가 철-유기리간드 골격체 100 중량부에 대하여, 50 중량부를 초과할 경우에는 탄소 전구체가 철-유기리간드 골격체 입자 밖에 과량 존재하게 되므로 표면적 및 세공 크기가 감소되고, 철 활성성분을 둘러싼 탄소체의 두께가 커져 촉매 활성이 낮아지는 문제점이 발생될 수 있다. 상기 탄소체의 두께는 10 nm ~ 100 nm인 것이 바람직하다.At this time, the carbon precursor may be added in an amount of less than 50 parts by weight based on 100 parts by weight of the iron-organic ligand framework. When the carbon precursor exceeds 50 parts by weight based on 100 parts by weight of the iron-organic ligand framework, the carbon precursor is present in excess outside the iron-organic ligand framework particles, thereby reducing the surface area and pore size, and removing the iron active ingredient. As the thickness of the surrounding carbon body increases, a problem may occur in which catalytic activity is lowered. The thickness of the carbon body is preferably 10 nm to 100 nm.
또한, 상기 탄소체의 비표면적은 100 m2/g 이상이고, 기공부피는 0.1 cm3/g 이상인 것이 바람직하다.In addition, the specific surface area of the carbon body is preferably 100 m 2 /g or more, and the pore volume is preferably 0.1 cm 3 /g or more.
상기 탄소 전구체는 퍼퓨릴알코올(furfuryl alcohol), 다이비닐벤젠(divinylbenzene), 우레아(urea), 글루코스(glucose), 수크로스 에틸렌 글리콜(sucrose etylene glycol), 글리세롤(glycerol), 자일리톨(xylitol) 및 멜라민(melamine)로 구성된 군에서 선택되는 1종 이상일 수 있다.The carbon precursor is furfuryl alcohol, divinylbenzene, urea, glucose, sucrose etylene glycol, glycerol, xylitol, and melamine. It may be one or more types selected from the group consisting of (melamine).
본 발명에 따른 촉매는 탄소 전구체를 첨가시켜 철-유기리간드 골격체의 탄소체 함량을 증가시킴으로써, 촉매활성을 유지하면서 유색 PET에 함유된 안료에 대한 흡착력을 향상시킬 수 있다.The catalyst according to the present invention can improve the adsorption capacity for pigments contained in colored PET while maintaining catalytic activity by increasing the carbon content of the iron-organic ligand skeleton by adding a carbon precursor.
또한, 본 발명은 상기의 폴리에틸렌테레프탈레이트(PET)의 해중합 반응용 촉매 존재하에서 폴리에틸렌테레프탈레이트와 글리콜과의 반응으로 BHET를 제조하는 것을 특징으로 하는 BHET의 제조방법을 제공한다.In addition, the present invention provides a method for producing BHET, characterized in that BHET is produced through a reaction between polyethylene terephthalate and glycol in the presence of a catalyst for the depolymerization reaction of polyethylene terephthalate (PET).
이때, 본 발명에 따른 상기의 폴리에틸렌테레프탈레이트(PET)의 해중합 반응용 촉매는 폴리에틸렌테레프탈레이트 100 중량부에 대하여 3 중량부 내지 20 중량부로 사용할 수 있다. 상기 범위를 만족하는 경우 글리콜리시스 반응 효율이 우수하고, 반응성을 높일 수 있는 측면에서 효과적이나, 이는 비한적인 일예일 뿐, 상기 수치범위에 제한받지 않는다.At this time, the catalyst for the depolymerization reaction of polyethylene terephthalate (PET) according to the present invention can be used in an amount of 3 to 20 parts by weight based on 100 parts by weight of polyethylene terephthalate. If the above range is satisfied, the glycolysis reaction efficiency is excellent and it is effective in increasing reactivity, but this is only a limited example and is not limited to the above numerical range.
상기 폴리에틸렌테레프탈레이트는 BHET를 제조하기 위한 반응원료로, 무색의 폴리에틸렌테레프탈레이트 및/또는 안료가 함유된 유색의 폴리에틸렌테레프탈레이트일 수 있으며, 신재 및/또는 사용후 폐기물일 수 있다. The polyethylene terephthalate is a reaction raw material for producing BHET, and may be colorless polyethylene terephthalate and/or colored polyethylene terephthalate containing pigments, and may be new material and/or used waste.
또한, 상기 글리콜은 에틸렌글리콜, 디에틸렌글리콜, 트리에틸렌글리콜, 글리세롤, 프로판디올, 부탄디올, 펜탄디올, 헥산디올 등의 1종 또는 2종 이상으로 사용될 수 있으며, 이에 제한되는 것은 아니다. 상기 글리콜은 폴리에틸렌테레프탈레이트 100 중량부에 대하여 100 내지 3000 중량부로 사용될 수 있으며, 바람직하게는 400 내지 2000 중량부 범위로 포함될 수 있다. 만일 글리콜의 함량이 폴리에틸렌테레프탈레이트 100 중량부에 대하여 100 중량부 미만일 경우에는 반응시간이 연장되며 고분자량의 PET 성분이 많이 잔류되는 문제점이 발생될 수 있고, 3000 중량부를 초과할 경우에는 잔류 글리콜 회수량이 많아짐에 따라 회수공정 시간이 길어지는 문제점이 발생될 수 있다.In addition, the glycol may be used as one or two or more types of ethylene glycol, diethylene glycol, triethylene glycol, glycerol, propanediol, butanediol, pentanediol, and hexanediol, but is not limited thereto. The glycol may be used in an amount of 100 to 3000 parts by weight, preferably in the range of 400 to 2000 parts by weight, based on 100 parts by weight of polyethylene terephthalate. If the glycol content is less than 100 parts by weight based on 100 parts by weight of polyethylene terephthalate, the reaction time may be extended and problems may arise in which a large amount of high molecular weight PET components remain, and if it exceeds 3000 parts by weight, residual glycol ash may occur. As the quantity increases, a problem may arise where the recovery process time becomes longer.
상기 폴리에틸렌테레프탈레이트와 글리콜의 해중합 반응은 대기압 하에서 180 ℃ 내지 250 ℃로 1 시간 ~ 10 시간 동안 수행할 수 있고, 바람직하게는 190 ℃ 내지 230 ℃로 1 시간 ~ 5 시간 일 수 있다. 상기 180 ℃ 미만으로 반응을 수행할 경우, 해중합 속도가 느리기 때문에 반응 시간이 지나치게 오래 걸릴 수 있고, 250 ℃ 초과시에는 글리콜의 휘발에 따라 반응기의 압력이 상승되고 생성된 BHET가 중합반응을 통해 Dimer 또는 올리고머로 전환되는 문제가 발생될 수 있다. 또한, 반응시간이 1시간 미만으로 반응을 수행할 경우, 해중합율이 낮아질 수 있고, 10 시간을 초과할 경우에는 해중합율의 변화가 없고, BHET monomer와 Dimer의 반응 평형이 이루어지기 때문에 반응 시간을 상기 범위로 유지하는 것이 바람직하다.The depolymerization reaction of polyethylene terephthalate and glycol can be performed under atmospheric pressure at 180°C to 250°C for 1 hour to 10 hours, and preferably at 190°C to 230°C for 1 hour to 5 hours. If the reaction is performed below 180°C, the reaction time may take too long because the depolymerization rate is slow, and if it exceeds 250°C, the pressure in the reactor increases due to the volatilization of glycol, and the produced BHET is converted into Dimer or Dimer through the polymerization reaction. Problems with conversion to oligomers may occur. In addition, if the reaction time is less than 1 hour, the depolymerization rate may be lowered, and if it exceeds 10 hours, there is no change in the depolymerization rate, and the reaction equilibrium between the BHET monomer and dimer is achieved, so the reaction time It is desirable to maintain it within the above range.
상기 반응 종료 후에는 100 ℃까지 온도를 낮춘 다음 반응기에서 생성물을 배출할 수 있다. 상기 해중합 반응에서 PET 합성 공정에서 발생되는 공정 슬러지와 PET에 존재하는 저비점 유기 화합물나 수분 등이 제거될 수 있으며, 촉매 회수시에는 자석을 이용하여 반응물 및 생성물로부터 분리 회수할 수 있다.After completion of the reaction, the temperature can be lowered to 100° C. and then the product can be discharged from the reactor. In the depolymerization reaction, process sludge generated in the PET synthesis process and low-boiling organic compounds or moisture present in PET can be removed, and when recovering the catalyst, it can be separated and recovered from the reactants and products using a magnet.
이하, 실시예를 통하여 본 발명을 더욱 상세히 설명하기로 한다. 이들 실시예는 단지 본 발명을 예시하기 위한 것이므로, 본 발명의 범위가 이들 실시예에 의해 제한되는 것으로 해석해서는 안 된다.Hereinafter, the present invention will be described in more detail through examples. These examples are merely for illustrating the present invention, and the scope of the present invention should not be construed as limited by these examples.
<제조예 1 : Fe＠C 촉매 제조><Preparation Example 1: Preparation of Fe@C catalyst>
중심금속이 철인 MIL-100(Fe) 10 g을 보트형 알루미나 도가니에 넣고, 도가니를 튜브형 퍼니스에 넣었다. Ar를 주입하면서 상온에서 800 ℃까지 5 ℃/min로 승온시키고, 800 ℃에서 3 시간동안 탄화시킨 다음, 상온에서 냉각하여 탄소체에 철이 캡슐화된 촉매(Fe＠C)를 제조하였다. 10 g of MIL-100 (Fe), whose core metal is iron, was placed in a boat-type alumina crucible, and the crucible was placed in a tube-type furnace. While injecting Ar, the temperature was raised from room temperature to 800°C at 5°C/min, carbonized at 800°C for 3 hours, and then cooled to room temperature to prepare a catalyst (Fe@C) with iron encapsulated in a carbon body.
상기 제조된 촉매는 전자 주사 현미경(SEM)(Tescan Mira 3 LMUFEG, 가속 전압: 10 kV) 및 투과전자 현미경(TEM)(Technai G2 Retrofit)을 이용하여 촉매 형태학적 특성을 측정하여 도 1에 나타내었다. The catalyst morphological characteristics of the prepared catalyst were measured using scanning electron microscopy (SEM) (Tescan Mira 3 LMUFEG, acceleration voltage: 10 kV) and transmission electron microscopy (TEM) (Technai G2 Retrofit), and are shown in Figure 1. .
도 1에 나타난 바와 같인 상기 제조된 촉매는 철이 탄소체로 둘러싸인 형태임을 확인할 수 있었다. It was confirmed that the prepared catalyst, as shown in Figure 1, had iron surrounded by a carbon body.
<제조예 2 : Fe＠C-FA 촉매 제조><Preparation Example 2: Preparation of Fe@C-FA catalyst>
에틸알코올 2 g에 분산된 퍼퓨릴알코올(furfuryl alcohol) 0.5 g을 중심금속이 철인 MIL-100(Fe) 1.0 g에 함침시킨 후 50 ℃에서 에틸알코올을 증발시키면서 퍼퓨릴알코올을 중합시켰다. 이후 보트형 알루미나 도가니에 넣고, 도가니를 튜브형 퍼니스에 넣었다. Ar를 주입하면서 상온에서 800 ℃까지 5 ℃/min로 승온시키고, 800 ℃에서 3 시간동안 탄화시킨 다음, 상온에서 냉각하여 탄소체에 철이 둘러싸인 촉매(Fe＠C-FA)를 제조하였다. 0.5 g of furfuryl alcohol dispersed in 2 g of ethyl alcohol was impregnated into 1.0 g of MIL-100 (Fe), whose central metal is iron, and then the furfuryl alcohol was polymerized while evaporating the ethyl alcohol at 50°C. Afterwards, it was placed in a boat-type alumina crucible, and the crucible was placed in a tube-type furnace. While injecting Ar, the temperature was raised from room temperature to 800°C at 5°C/min, carbonized at 800°C for 3 hours, and then cooled to room temperature to prepare a catalyst (Fe@C-FA) with iron surrounded by a carbon body.
<비교제조예 1 : Fe<Comparative Manufacturing Example 1: Fe 33 OO 44 /C 촉매 제조>/C Catalyst Preparation>
활성탄 (Sigma-Aldrich) 1.0 g과 Fe(NO3)3·9H2O 0.362 g을 탈기된 증류수 50 ml이 포함된 250 ml 3구 플라스크에 넣고, 상온의 초음파 수조에서 60 분간 분산시킨 다음, Ethylene Diamine 0.9 g을 첨가한 후 30 분간 초음파 처리하여 분산시켰다. 이후 100 ml 수열반응기에 넣고 180 ℃, 400 rpm 조건에서 12 시간 동안 반응시킨 후 냉각시켜 여과하였다. 여과된 물질은 탈기된 증류수 250 ml 및 무수 에탄올 100 ml를 이용하여 세척하고, 100 ℃에서 24시간 동안 건조한 후 500 ℃, Ar 조건에서 소성하여 철이 활성탄에 담지된 형태의 촉매(Fe3O4/C)를 제조하였다.Place 1.0 g of activated carbon (Sigma-Aldrich) and 0.362 g of Fe(NO 3 ) 3 ·9H 2 O in a 250 ml three-necked flask containing 50 ml of degassed distilled water, disperse in an ultrasonic bath at room temperature for 60 minutes, and then dissolve in ethylene. After adding 0.9 g of diamine, it was dispersed by sonication for 30 minutes. Afterwards, it was placed in a 100 ml hydrothermal reactor and reacted at 180°C and 400 rpm for 12 hours, then cooled and filtered. The filtered material was washed with 250 ml of degassed distilled water and 100 ml of absolute ethanol, dried at 100 ℃ for 24 hours, and then calcined at 500 ℃ under Ar conditions to produce a catalyst in the form of iron supported on activated carbon (Fe 3 O 4 / C) was prepared.
<실시예 1><Example 1>
실시예 1-1Example 1-1
250 ml 3구 플라스크에 0.5 cm × 0.5 cm 크기로 세절된 폴리에틸렌테레프탈레이트(PET, 롯데케미칼) 2 g, 에틸렌글리콜(EG) 20 g 및 제조예 1에서 제조된 촉매 0.1 g를 투입하고, 혼합물을 환류 시스템하에서 190 ℃, 3 시간동안 400 rpm으로 교반하여 해중합 반응을 수행하였다. 반응완료 후 자성을 이용하여 촉매를 분리 회수하고, 고온에서 여과하여 미반응된 고온에서 여과하여 미반응된 PET를 제거한 다음, HPLC를 이용하여 BHET 수율 및 Dimer 등 부산물 수율을 계산하였다. 여과된 미반응 PET는 증류수 및 Acetone으로 세척하고, 건조시킨 다음 질량을 측정하여 PET 전환을 계산하였다.2 g of polyethylene terephthalate (PET, Lotte Chemical), 20 g of ethylene glycol (EG), and 0.1 g of the catalyst prepared in Preparation Example 1, cut into pieces of 0.5 cm Depolymerization reaction was performed under a reflux system at 190°C and stirring at 400 rpm for 3 hours. After completion of the reaction, the catalyst was separated and recovered using magnetism, unreacted PET was removed by filtration at high temperature, and then the BHET yield and the yield of by-products such as dimer were calculated using HPLC. The filtered unreacted PET was washed with distilled water and Acetone, dried, and then its mass was measured to calculate PET conversion.
실시예 1-2 내지 실시예 1-6Example 1-2 to Example 1-6
실시예 1-1과 동일한 방법으로 BHET를 제조하되, 표 1에 기재된 촉매 함량 및 에틸렌글리콜 함량으로 BHET를 제조하였다.BHET was prepared in the same manner as in Example 1-1, except that BHET was prepared with the catalyst content and ethylene glycol content listed in Table 1.
<실시예 2 내지 4><Examples 2 to 4>
실시예 1-1과 동일한 방법으로 BHET를 제조하되, 표 1에 기재된 조건으로 BHET를 제조하였다.BHET was prepared in the same manner as in Example 1-1, but under the conditions shown in Table 1.
<비교예 1><Comparative Example 1>
실시예 1-1과 동일한 방법으로 BHET를 제조하되, 촉매를 첨가하지 않고 BHET를 제조하였다.BHET was prepared in the same manner as Example 1-1, but without adding a catalyst.
<비교예 2 내지 5><Comparative Examples 2 to 5>
실시예 1-1과 동일한 방법으로 BHET를 제조하되, 표 1에 기재된 조건으로 BHET를 제조하였다.BHET was prepared in the same manner as in Example 1-1, but under the conditions shown in Table 1.
하기 표에서 무색 PET는 폴리에틸렌테레프탈레이트(PET, 롯데케미칼)이며, 주황색 PET는 (PET, LG생활건강)을 사용하였다. In the table below, colorless PET is polyethylene terephthalate (PET, Lotte Chemical), and orange PET is (PET, LG Household & Health Care).
(g)EG
(g)
온도
(℃)reaction
temperature
(℃)
시간
(hr)reaction
hour
(hr)
<실험예 1 : 촉매 특성평가><Experimental Example 1: Evaluation of catalyst characteristics>
제조예 1 및 2에서 제조된 촉매의 특성을 평가하기 위해 비표면적은 질소흡착 결과로부터 브루나우어-에메트-텔레(Brunauer-Emmett-Teller, BET) 방법을 사용하여 평가하고, 기공부피는 P/P0 = 0.99에서 단일 포인트법에 의해 측정하였으며, 세공 크기 분포는 바렛-조이너-할렌다(Barrett-Joyner-Halenda) 방법을 사용하여 측정하여 표 2에 각각 나타내었다.To evaluate the properties of the catalysts prepared in Preparation Examples 1 and 2, the specific surface area was evaluated using the Brunauer-Emmett-Teller (BET) method from the nitrogen adsorption results, and the pore volume was P It was measured by the single point method at /P0 = 0.99, and the pore size distribution was measured using the Barrett-Joyner-Halenda method and is shown in Table 2.
표 2에 나타난 바와 같이, 제조예 1의 촉매에 탄소 전구체가 혼합된 제조예 2의 촉매의 경우 기공부피가 감소한 것과 동시에 제조예 1의 촉매에 비해 비표면적이 증가된 것으로 나타났다.As shown in Table 2, in the case of the catalyst of Preparation Example 2 in which a carbon precursor was mixed with the catalyst of Preparation Example 1, the pore volume was decreased and the specific surface area was increased compared to the catalyst of Preparation Example 1.
<실험예 2 : 촉매 활성평가><Experimental Example 2: Catalyst activity evaluation>
촉매 함량에 따른 BHET 수득율 비교 분석하기 위해 실시예 1-1 내지 1-6에서 수득된 BHET에 대한 PET 전환율과 BHET 수율을 하기 식 1 및 2로 각각 계산하고, 그 결과를 하기 표 3에 나타내었다. 표 3에서의 촉매는 모두 제조예1에서 제조된 철이 탄소체에 의해 둘러싸인 형태인 Fe＠C이고, PET는 무색 PET가 사용되었다.In order to compare and analyze the BHET yield according to catalyst content, the PET conversion rate and BHET yield for the BHET obtained in Examples 1-1 to 1-6 were calculated using Equations 1 and 2 below, respectively, and the results are shown in Table 3 below. . The catalysts in Table 3 are all Fe@C, which is a form of iron prepared in Preparation Example 1 surrounded by a carbon body, and colorless PET was used as PET.
또한, 촉매 종류에 따른 BHET 수득율 비교 분석하기 위해 실시예 1-1, 실시예 3 및 비교예 1, 2, 4에서 수득된 BHET에 대한 PET 전환율과 BHET 수율을 하기 식 1 및 2로 각각 계산하고, 그 결과를 하기 표 4에 나타내었다. 표 4에서의 PET는 무색 PET가 사용되었다.In addition, in order to comparatively analyze BHET yield according to catalyst type, the PET conversion rate and BHET yield for BHET obtained in Examples 1-1, Example 3, and Comparative Examples 1, 2, and 4 were calculated using the following equations 1 and 2, respectively. , the results are shown in Table 4 below. The PET in Table 4 was colorless PET.
[식 1] PET 전환율(%) = {(초기 PET 질량(g) - (반응 후 PET 질량(g))/(초기 PET 질량(g))} × 100[Equation 1] PET conversion rate (%) = {(initial PET mass (g) - (PET mass after reaction (g))/(initial PET mass (g))} × 100
[식 2] BHET 수율(%) = {(생성된 BHET 몰 수)/(초기 PET 몰 수)} × 100[Formula 2] BHET yield (%) = {(number of moles of BHET produced)/(number of moles of initial PET)} × 100
(g)EG
(g)
전환율
(%)PET
conversion rate
(%)
수율
(%)BHET
transference number
(%)
수율
(%)Dimer
transference number
(%)
표 3에 나타난 바와 같이, EG의 중량이 PET 중량의 10배인 조건하에서 촉매 함량(PET의 중량대비 촉매의 wt%)에 따라서 PET 전환율과 BHET 수율이 변화되는 것으로 나타났고, 특히 촉매 함량이 1.0 wt% 이상인 경우 PET의 전환율이 97 %이상이고, BHET 수율이 94 %이상인 것을 확인할 수 있었다. 또한, 실시예 1-6에서와 같이 PET에 대한 EG의 비율이 감소하게되면 BHET 수율이 감소되는 것을 알 수 있다.As shown in Table 3, under the condition that the weight of EG is 10 times the weight of PET, the PET conversion rate and BHET yield were found to change depending on the catalyst content (wt% of catalyst compared to the weight of PET), especially when the catalyst content was 1.0 wt. % or more, it was confirmed that the PET conversion rate was over 97% and the BHET yield was over 94%. Additionally, as in Examples 1-6, it can be seen that when the ratio of EG to PET decreases, the BHET yield decreases.
(g)EG
(g)
전환율
(%)PET
conversion rate
(%)
수율
(%)BHET
transference number
(%)
수율
(%)Dimer
transference number
(%)
표 4에 나타난 바와 같이, 촉매를 넣지 않은 비교예1은 PET 전환이 거의 이루어지지 아니하였으며, 촉매를 사용한 경우에서는 확연히 PET 전환율이 증가하는 경향을 보였다.As shown in Table 4, in Comparative Example 1 without a catalyst, almost no PET conversion occurred, and when a catalyst was used, the PET conversion rate clearly tended to increase.
그러나, 본 발명에 따라, 철입자 표면에 탄소가 코팅되도록 제조한 실시예 1-1 및 3의 PET 전환율과 BHET 수율이 비교예 1, 2 및 4의 PET 전환율과 BHET 수율보다 높은 것으로 나타났다.However, according to the present invention, the PET conversion rate and BHET yield of Examples 1-1 and 3, which were manufactured so that carbon was coated on the surface of the iron particles, were found to be higher than the PET conversion rate and BHET yield of Comparative Examples 1, 2, and 4.
<실험예 3 : 촉매의 재사용에 따른 촉매 활성 측정><Experimental Example 3: Measurement of catalyst activity according to reuse of catalyst>
촉매의 재사용에 따른 활성을 측정하기 위해 제조예 1의 촉매를 사용하여 실시예 1-1와 동일한 방법으로 반응 진행하고, 반응이 완료된 뒤, 반응에 사용된 촉매를 그대로 재사용하여 다시 동일한 반응을 실시하는 실험을 20회 반복 수행하였다. 각각의 반응이 완결된 후, 생성물을 회수하여 분석하였으며, 그 결과를 하기 표 5에 나타내었다. 또한 각각의 반응이 완결된 뒤의 촉매의 XRD 데이터를 분석하여 그 결과를 도 2에 나타내었다. To measure the activity due to reuse of the catalyst, the reaction was performed in the same manner as Example 1-1 using the catalyst of Preparation Example 1, and after the reaction was completed, the catalyst used in the reaction was reused and the same reaction was performed again. The experiment was repeated 20 times. After each reaction was completed, the product was recovered and analyzed, and the results are shown in Table 5 below. Additionally, the XRD data of the catalyst after each reaction was completed was analyzed and the results are shown in Figure 2.
표 5에 나타난 바와 같이, 제조예 1의 촉매의 경우 20회 반복 재사용하여도 PET의 전환율이 100 %이고, BHET 선택도가 96 % 이상인 것으로 나타남에 따라 본 발명에 따른 촉매의 경우 여러번의 재사용에도 촉매활성 성분의 침출 없이 촉매 활성을 그대로 유지함을 확인할 수 있었다. As shown in Table 5, in the case of the catalyst of Preparation Example 1, the PET conversion rate was 100% and the BHET selectivity was 96% or more even after repeated reuse 20 times, so the catalyst according to the present invention could be reused even multiple times. It was confirmed that the catalytic activity was maintained without leaching of the catalytically active ingredients.
또한, 도 2에 나타난 바와 같이 해중합 반응이 반복 수행할 때마다 촉매의 XRD 데이터에 나타난 피크의 크기가 변함이 없이 유지되고 있어 재사용시에도 촉매의 활성 및 성분이 안정적으로 유지됨을 확인할 수 있었다.In addition, as shown in Figure 2, the size of the peak in the XRD data of the catalyst remained unchanged every time the depolymerization reaction was repeated, confirming that the activity and components of the catalyst were stably maintained even when reused.
반면, 촉매활성 성분이 탄소체로 둘러싸이지 않은 비교제조예 1의 촉매의 경우 반응 활성이 낮고(PET 전환율 42.7%), 재사용 시에는 촉매가 침출되어 급격히 비활성화됨을 확인할 수 있었다(하기 표 6 참조). On the other hand, in the case of the catalyst of Comparative Preparation Example 1 in which the catalytically active component was not surrounded by a carbon body, the reaction activity was low (PET conversion rate 42.7%), and upon reuse, it was confirmed that the catalyst was leached and rapidly deactivated (see Table 6 below).
<실험예 5 : 유색 PET 적용에 따른 촉매 활성 측정><Experimental Example 5: Measurement of catalytic activity according to application of colored PET>
유색 PET의 해중합 반응에 있어서, 촉매 종류에 따른 BHET 수득율 비교 분석하기 위해 실시예 2 및 4와 비교예 3 및 5에서 수득된 BHET에 대한 PET 전환율과 BHET 수율을 식 1 및 2로 각각 계산하고, 수득된 BHET에 함유된 안료 유무를 육안으로 관찰하였다. In the depolymerization reaction of colored PET, in order to compare and analyze the BHET yield according to the type of catalyst, the PET conversion rate and BHET yield for the BHET obtained in Examples 2 and 4 and Comparative Examples 3 and 5 were calculated using Equations 1 and 2, respectively, The presence or absence of pigment contained in the obtained BHET was observed with the naked eye.
실시예 2 및 4에서 수득된 BHET의 경우, 비교예 3 및 5에서 수득된 BHET 보다 육안으로 관찰시에도 주황색이 확연히 제거된 것을 나타나므로 안료가 제거됨을 확인할 수 있었다. 특히 실시예 4에서 수득된 BHET의 경우, 무색 PET로부터 수득된 실시예 1의 BHET와 유사한 투명도를 나타냄을 확인할 수 있었다. In the case of the BHET obtained in Examples 2 and 4, the orange color was clearly removed when observed with the naked eye compared to the BHET obtained in Comparative Examples 3 and 5, confirming that the pigment was removed. In particular, it was confirmed that the BHET obtained in Example 4 exhibited transparency similar to that of the BHET in Example 1 obtained from colorless PET.
<실험예 6 : 유색 PET 적용에 따른 촉매 안정성 평가><Experimental Example 6: Catalyst stability evaluation according to application of colored PET>
유색 PET의 해중합 반응에 있어서, 촉매의 재사용에 따른 안정성을 측정하기 위해 제조예 1의 촉매가 적용된 실시예 1-1과 동일한 방법으로 반응을 진행하고, 반응이 완료된 뒤, 반응에 사용된 촉매를 그대로 재사용하여 동일한 방법으로 실험을 10회 반복 수행하였다. 각각의 반응이 완결된 후, 생성된 생성물의 수득율 및 전환율을 측정하여 표 8에 나타내었다.In the depolymerization reaction of colored PET, in order to measure the stability of the catalyst upon reuse, the reaction was carried out in the same manner as Example 1-1 using the catalyst of Preparation Example 1, and after the reaction was completed, the catalyst used in the reaction was It was reused as is and the experiment was repeated 10 times in the same manner. After each reaction was completed, the yield and conversion rate of the produced product were measured and shown in Table 8.
또한, 제조예 2의 촉매가 적용된 실시예 2와 동일한 방법으로 반응을 반응이 완료된 뒤, 반응에 사용된 촉매를 그대로 재사용하여 동일한 방법으로 실험을 3회 반복 수행하였다. 각각의 반응이 완결된 후, 생성된 BHET의 색변화를 관찰한 결과, 반복 사용에도 원료의 색에 비하여 높은 정도로 탈색되어 주황색을 띄는 안료가 반복 사용에도 제거되는 것으로 나타났다.In addition, the reaction was performed in the same manner as in Example 2 in which the catalyst of Preparation Example 2 was applied. After the reaction was completed, the catalyst used in the reaction was reused and the experiment was repeated three times in the same manner. After each reaction was completed, the color change of the produced BHET was observed, and it was found that even with repeated use, the orange pigment was removed to a higher degree compared to the color of the raw material.
따라서, 본 발명에 따른 촉매는 PET의 글리콜리시스 해중합 반응에서 높은 수율로 BHET을 생성시킬 수 있는 동시에 내구성이 우수하며 촉매의 회수 및 재사용이 유리하여 촉매를 반복 재사용하더라도 수율을 그대로 유지할 수 있음을 확인할 수 있었다. 또한, 안료가 함유된 유색 PET의 글리콜리시스 해중합 반응에 있어서도 안료의 제거와 동시에 고수율로 BHET을 수득할 수 있음을 확인할 수 있었다.Therefore, the catalyst according to the present invention is capable of producing BHET in high yield in the glycolysis depolymerization reaction of PET, has excellent durability, and is advantageous in recovery and reuse of the catalyst, so the yield can be maintained even if the catalyst is repeatedly reused. I was able to confirm. In addition, it was confirmed that in the glycolysis depolymerization reaction of colored PET containing pigment, BHET can be obtained in high yield at the same time as the pigment is removed.
상기 본 발명은 전술한 실시예에 의해 한정되는 것이 아니고, 본 발명의 기술적 사상을 벗어나지 않는 범위 내에서 여러 가지 치환, 변형 및 변경이 가능하다는 것이 본 발명이 속하는 기술분야에서 통상의 지식을 가진 자에게 명백할 것이다.The present invention is not limited to the above-described embodiments, and it is understood by those skilled in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be clear to
Claims (11)
상기 촉매는 촉매활성 성분인 철이 탄소체에 의해 둘러싸여 있어, 촉매 활성물질이 침출되거나 소실되지 않는 것을 특징으로 하는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매.
In the catalyst for the depolymerization reaction of polyethylene terephthalate,
The catalyst is a catalyst for the depolymerization reaction of polyethylene terephthalate, wherein iron, a catalytically active component, is surrounded by a carbon body, so that the catalytically active material is not leached or lost.
상기 촉매는 철-유기리간드 골격체를 탄화시켜 형성된 것을 특징으로 하는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매.
According to paragraph 1,
A catalyst for the depolymerization reaction of polyethylene terephthalate, characterized in that the catalyst is formed by carbonizing an iron-organic ligand skeleton.
상기 철-유기리간드 골격체는 철(Fe)이 중심금속으로 된 MOF인 것을 특징으로 하는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매.
According to paragraph 2,
A catalyst for the depolymerization reaction of polyethylene terephthalate, wherein the iron-organic ligand skeleton is a MOF with iron (Fe) as the central metal.
상기 폴리에틸렌테레프탈레이트의 해중합 반응은 폴리에틸렌테레프탈레이트와 글리콜과의 반응인 것을 특징으로 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매.
According to paragraph 1,
A catalyst for the depolymerization reaction of polyethylene terephthalate, wherein the depolymerization reaction of polyethylene terephthalate is a reaction between polyethylene terephthalate and glycol.
철-유기리간드 골격체를 불활성 분위기에서 탄화시키는 단계를 포함하여, 촉매활성 성분인 철(Fe)이 탄소체를 포함하는 물질로 둘러싸이도록 하여, 촉매 활성물질이 침출되거나 소실되지 않게 하는 것을 특징으로 하는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매의 제조방법.
In the method for producing a catalyst for the depolymerization reaction of polyethylene terephthalate,
It includes the step of carbonizing the iron-organic ligand framework in an inert atmosphere, so that iron (Fe), a catalytically active component, is surrounded by a material containing a carbon body, thereby preventing the catalytically active material from being leached or lost. Method for producing a catalyst for depolymerization reaction of polyethylene terephthalate.
상기 철-유기리간드 골격체는 철(Fe)이 중심금속으로 된 MOF인 것을 특징으로 하는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매의 제조방법.
According to clause 5,
A method for producing a catalyst for the depolymerization reaction of polyethylene terephthalate, wherein the iron-organic ligand skeleton is a MOF with iron (Fe) as the central metal.
상기 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매의 제조방법은 철-유기리간드 골격체의 탄소화 전에 철-유기리간드 골격체에 탄소 전구체를 더 포함하여 탄소화를 수행하는 것을 특징으로 하는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매의 제조방법.
According to clause 5,
The method for producing a catalyst for the depolymerization reaction of polyethylene terephthalate is characterized in that carbonization is performed by further including a carbon precursor in the iron-organic ligand framework before carbonization of the iron-organic ligand framework. Method for producing a catalyst for reaction.
상기 탄소 전구체는 퍼퓨릴알코올(furfuryl alcohol), 다이비닐벤젠(divinylbenzene), 우레아(urea), 글루코스(glucose), 수크로스 에틸렌글리콜(sucrose etylene glycol), 글리세롤(glycerol), 자일리톨(xylitol) 및 멜라민(melamine)으로 구성된 군에서 선택되는 1종 이상인 것을 특징으로 하는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매의 제조방법.
In clause 7,
The carbon precursor is furfuryl alcohol, divinylbenzene, urea, glucose, sucrose etylene glycol, glycerol, xylitol, and melamine. A method for producing a catalyst for the depolymerization reaction of polyethylene terephthalate, characterized in that it is one or more selected from the group consisting of (melamine).
상기 탄화는 600 ℃ ~ 1200 ℃에서 수행하는 것을 특징으로 하는 폴리에틸렌테레프탈레이트의 해중합 반응용 촉매의 제조방법.
According to clause 5,
A method for producing a catalyst for the depolymerization reaction of polyethylene terephthalate, characterized in that the carbonization is performed at 600 ° C. to 1200 ° C.
A method for producing BHET, characterized in that BHET is produced by reacting polyethylene terephthalate with glycol in the presence of the catalyst for depolymerization of polyethylene terephthalate according to any one of claims 1 to 4.
상기 글리콜은 폴리에틸렌테레프탈레이트 100 중량부에 대하여, 100 내지 3000 중량부인 것을 특징으로 하는 BHET의 제조방법.
According to clause 10,
A method for producing BHET, characterized in that the glycol is used in an amount of 100 to 3000 parts by weight based on 100 parts by weight of polyethylene terephthalate.
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| Tianlin Wang et al, Fabrication of magnetic bimetallic Co-Zn based zeolitic imidazolate frameworks composites as catalyst of glycolysis of mixed plastic, Fuel 304, 121397,1~10쪽, 2021.8.9.온라인 공개 |
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