JP2007224113A - Method for recovering effective components from recovered biodegradable polyester - Google Patents
Method for recovering effective components from recovered biodegradable polyester Download PDFInfo
- Publication number
- JP2007224113A JP2007224113A JP2006045058A JP2006045058A JP2007224113A JP 2007224113 A JP2007224113 A JP 2007224113A JP 2006045058 A JP2006045058 A JP 2006045058A JP 2006045058 A JP2006045058 A JP 2006045058A JP 2007224113 A JP2007224113 A JP 2007224113A
- Authority
- JP
- Japan
- Prior art keywords
- biodegradable polyester
- recovered
- product
- polylactic acid
- reaction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229920000229 biodegradable polyester Polymers 0.000 title claims abstract description 53
- 239000004622 biodegradable polyester Substances 0.000 title claims abstract description 53
- 238000000034 method Methods 0.000 title claims abstract description 19
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 34
- 239000000203 mixture Substances 0.000 claims abstract description 13
- 239000000178 monomer Substances 0.000 claims abstract description 12
- JVTAAEKCZFNVCJ-UHFFFAOYSA-N lactic acid Chemical group CC(O)C(O)=O JVTAAEKCZFNVCJ-UHFFFAOYSA-N 0.000 claims description 52
- 229920000747 poly(lactic acid) Polymers 0.000 claims description 50
- 239000004626 polylactic acid Substances 0.000 claims description 48
- 238000012691 depolymerization reaction Methods 0.000 claims description 34
- 239000004310 lactic acid Substances 0.000 claims description 26
- 235000014655 lactic acid Nutrition 0.000 claims description 26
- 238000011084 recovery Methods 0.000 claims description 20
- JJTUDXZGHPGLLC-UHFFFAOYSA-N lactide Chemical group CC1OC(=O)C(C)OC1=O JJTUDXZGHPGLLC-UHFFFAOYSA-N 0.000 claims description 14
- 239000004480 active ingredient Substances 0.000 claims description 11
- 238000006460 hydrolysis reaction Methods 0.000 abstract description 5
- 239000000047 product Substances 0.000 description 34
- 238000006243 chemical reaction Methods 0.000 description 24
- 239000000463 material Substances 0.000 description 14
- 239000007795 chemical reaction product Substances 0.000 description 10
- 230000035484 reaction time Effects 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 3
- 239000000539 dimer Substances 0.000 description 3
- 238000006116 polymerization reaction Methods 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 229930182843 D-Lactic acid Natural products 0.000 description 2
- JVTAAEKCZFNVCJ-UWTATZPHSA-N D-lactic acid Chemical compound C[C@@H](O)C(O)=O JVTAAEKCZFNVCJ-UWTATZPHSA-N 0.000 description 2
- 239000007864 aqueous solution Substances 0.000 description 2
- 229940022769 d- lactic acid Drugs 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- VLTRZXGMWDSKGL-UHFFFAOYSA-N perchloric acid Chemical compound OCl(=O)(=O)=O VLTRZXGMWDSKGL-UHFFFAOYSA-N 0.000 description 2
- 229920001432 poly(L-lactide) Polymers 0.000 description 2
- 229920000728 polyester Polymers 0.000 description 2
- -1 polyethylene Polymers 0.000 description 2
- 239000002028 Biomass Substances 0.000 description 1
- 239000004952 Polyamide Substances 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 229920000954 Polyglycolide Polymers 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 229920002472 Starch Polymers 0.000 description 1
- BZHJMEDXRYGGRV-UHFFFAOYSA-N Vinyl chloride Chemical compound ClC=C BZHJMEDXRYGGRV-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 229920003232 aliphatic polyester Polymers 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 229920000704 biodegradable plastic Polymers 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000004566 building material Substances 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000007809 chemical reaction catalyst Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 229910000365 copper sulfate Inorganic materials 0.000 description 1
- ARUVKPQLZAKDPS-UHFFFAOYSA-L copper(II) sulfate Chemical compound [Cu+2].[O-][S+2]([O-])([O-])[O-] ARUVKPQLZAKDPS-UHFFFAOYSA-L 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003480 eluent Substances 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 235000013305 food Nutrition 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- VQHSOMBJVWLPSR-UHFFFAOYSA-N lactitol Chemical compound OCC(O)C(O)C(C(O)CO)OC1OC(CO)C(O)C(O)C1O VQHSOMBJVWLPSR-UHFFFAOYSA-N 0.000 description 1
- 235000010448 lactitol Nutrition 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 238000006384 oligomerization reaction Methods 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 229920001610 polycaprolactone Polymers 0.000 description 1
- 239000004632 polycaprolactone Substances 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 239000004633 polyglycolic acid Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 229920000098 polyolefin Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 229920000915 polyvinyl chloride Polymers 0.000 description 1
- 239000004800 polyvinyl chloride Substances 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 238000007151 ring opening polymerisation reaction Methods 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
- UQDJGEHQDNVPGU-UHFFFAOYSA-N serine phosphoethanolamine Chemical compound [NH3+]CCOP([O-])(=O)OCC([NH3+])C([O-])=O UQDJGEHQDNVPGU-UHFFFAOYSA-N 0.000 description 1
- 235000019698 starch Nutrition 0.000 description 1
- 239000008107 starch Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Classifications
-
- 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
- C08J11/14—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 steam or water
-
- 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
- C08J2367/04—Polyesters derived from hydroxy carboxylic acids, e.g. lactones
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Heterocyclic Compounds That Contain Two Or More Ring Oxygen Atoms (AREA)
Abstract
Description
本発明は、生分解性ポリエステル回収物を、水を用いて解重合反応させ、解重合生成物として該生分解性ポリエステルのモノマー、該生分解性ポリエステルのオリゴマー等の混合物として回収する、生分解性ポリエステル回収物から、有効成分を回収する方法に関する。 In the present invention, a biodegradable polyester recovery product is subjected to a depolymerization reaction using water, and recovered as a depolymerization product as a mixture of the biodegradable polyester monomer, the biodegradable polyester oligomer, and the like. The present invention relates to a method for recovering an active ingredient from a recovered polyester.
ポリ乳酸は、従来から、環境への負荷が少ない生分解性プラスチックの代表としてよく知られてきた。近年、循環型社会構築気運が高まり、プラスチック原料が化石資源からバイオマスへ転換する動きがあり、デンプンなど植物が原料となるポリ乳酸が大きな注目を集めている。このポリ乳酸は、その物性として透明性に優れ、成形加工の多様性があり、安全性も高いため、農林水産用資材、土木・建築資材、食品包装・容器、又は日用品用途などでの各方面での使用が期待されている。 Conventionally, polylactic acid has been well known as a representative of biodegradable plastics that have a low environmental impact. In recent years, the trend of building a recycling-oriented society has increased, and plastic raw materials have been moved from fossil resources to biomass, and polylactic acid from plants such as starch has attracted much attention. This polylactic acid has excellent transparency, has a wide variety of molding processes, and is highly safe, so it can be used in various fields such as agricultural, forestry and fishery materials, civil engineering / building materials, food packaging / containers, or daily necessities. Use in is expected.
しかしながら、上記のような使用の増大に伴って大量に発生する、使用済みポリ乳酸、
およびポリ乳酸製造段階で発生する品質不適格品（以下、これらをポリ乳酸回収物と略称
することがある。）については、ポリ乳酸部位は生分解性を有するものの分解までに長時
間を要し、またポリ乳酸以外の部位は生分解性を有さないことが多くそのまま自然界に残り、今後大きな社会問題となることが予想される。上記の問題に対して、ポリ乳酸回収物を元の原料に変換・回収し、この原料から再度重合反応等によってポリ乳酸ポリマーを製造し再利用する、いわゆるケミカルリサイクルが有効である。この方法は、基本的にロスの無い、化合物の資源再使用が可能な方法であり、資源の再利用が可能となる。
However, used polylactic acid, which is generated in large quantities with increasing use as described above,
In addition, for non-qualified products generated in the polylactic acid production stage (hereinafter, these may be abbreviated as polylactic acid recovered products), although the polylactic acid portion is biodegradable, it takes a long time to decompose. In addition, parts other than polylactic acid often do not have biodegradability and remain in the natural world, and are expected to become a major social problem in the future. In order to solve the above problems, so-called chemical recycling is effective, in which a polylactic acid recovery product is converted and recovered to an original raw material, and a polylactic acid polymer is produced from the raw material again by a polymerization reaction or the like and reused. This method is basically a loss-free method that enables resource reuse of compounds, and enables resource reuse.
例えば、水存在したで加水分解反応を用いる方法として、約２００℃〜約３５０℃の高温下で、ポリ乳酸に対し大量の水を使用し完全に乳酸まで変換させる方法が提案されている（例えば特許文献１参照。）。 For example, as a method of using a hydrolysis reaction in the presence of water, a method has been proposed in which polylactic acid is completely converted to lactic acid using a large amount of water at a high temperature of about 200 ° C. to about 350 ° C. (for example, (See Patent Document 1).
しかしながら、高温条件下、加水分解反応のために大量の水を用いるため、その使用する水量の分エネルギー使用量が増加し、更に最終的にポリ乳酸とするためにはその使用した水を留去させる必要があり、この段階でもエネルギー使用量が増加するという問題がある。
本発明の目的は、従来技術が有していた問題点を解決し、ポリ乳酸回収物の加水分解反応を実施する際、使用するエネルギー量を増やさずに、ポリ乳酸回収物から有効成分を回収するする方法を提供することにある。 The object of the present invention is to solve the problems of the prior art and recover the active ingredient from the polylactic acid recovery product without increasing the amount of energy used when the hydrolysis reaction of the polylactic acid recovery product is carried out. It is to provide a way to do.
本発明者らは上記従来技術に鑑み、鋭意検討を行った結果、本発明を完成するに至った。すなわち、本発明は、生分解性ポリエステル回収物を８０℃〜３００℃の温度下で、生分解性ポリエステル回収物に対して５重量倍以下である水を用いて解重合反応を行い、解重合生成物として該生分解性ポリエステルのモノマー、該生分解性ポリエステルのモノマー及びオリゴマーの混合物、又は該生分解性ポリエステルのオリゴマーとして回収する方法である。 As a result of intensive studies in view of the above-described prior art, the present inventors have completed the present invention. That is, the present invention performs a depolymerization reaction of the biodegradable polyester recovered material at a temperature of 80 ° C. to 300 ° C. using water that is 5 times by weight or less of the biodegradable polyester recovered material. The biodegradable polyester monomer is recovered as a product, a mixture of the biodegradable polyester monomer and oligomer, or the biodegradable polyester oligomer.
本発明の方法によれば、生分解性ポリエステル回収物から水を用いた解重合反応によって、生分解性ポリエステルのモノマー、ラクチド、オリゴマー等の混合物を有効成分として回収する場合、使用する水の量を低減することにより使用するエネルギー量を増やさずに有効成分を回収することが可能である。また、同容量の解重合槽では、使用する水の量を低減した分、生分解性ポリエステル回収物の投入量を増加することができ、処理量を増加させることもできる。特に生分解性ポリエステルがポリ乳酸である場合には期待できる。 According to the method of the present invention, when a mixture of biodegradable polyester monomers, lactides, oligomers, etc. is recovered as an active ingredient by a depolymerization reaction using water from a biodegradable polyester recovery product, the amount of water used It is possible to recover the active ingredient without increasing the amount of energy used. Moreover, in the depolymerization tank of the same capacity, the input amount of the biodegradable polyester recovered product can be increased by the amount of water used, and the processing amount can be increased. This can be expected particularly when the biodegradable polyester is polylactic acid.
本発明において、生分解性ポリエステル回収物とはポリ乳酸、ポリグリコール酸、ポリカプロラクトン等の生分解性ポリエステルを含んでいる回収物である。好ましくはその主成分がポリ乳酸であり、生分解性ポリエステル回収物全体の６０重量％以上含むものが好ましく、より好ましくは８０重量％以上である。ポリ乳酸については、ポリＬ−乳酸、ポリＤ−乳酸、ラセミ状のポリ乳酸、ポリＬ−乳酸とポリＤ−乳酸の混合物、ポリ乳酸ステレオコンプレックスポリマーなど各種ポリ乳酸に適用できる。更に、生分解性ポリエステル回収物には、一旦市場で製品として用いられたものを回収してきたものを主として指すので、生分解性ポリエステル以外に種々の異素材を含む。この異素材としてはポリエチレン、ポリプロピレン、若しくはポリ塩化ビニル等のポリオレフィン類、生分解性でない脂肪族ポリエステル、芳香族ポリエステル類、ポリアミド類、紙、土砂、埃、金属類、残存触媒、又は木材などが挙げられる。また、さらに本発明の方法においては、生分解性ポリエステル回収物は一般に水洗浄及び粗粉砕などの前処理を施し、解重合反応に適した形状にしてから投入することが好ましい。この際に水に極めて易溶な異素材も取り除くことができるので好ましい。またこの前処理を行う前及び／又は行った後で、簡易的な機械的又は物理的手段によって可能な限り生分解性ポリエステル回収物から異素材を取り除くことが好ましい。例えば目視で異素材と判別できるものを取り除く方法、又は磁石を用いて磁石に吸い付けられる金属類を取り除くなどの方法である。 In the present invention, the biodegradable polyester recovered material is a recovered material containing biodegradable polyester such as polylactic acid, polyglycolic acid, polycaprolactone and the like. Preferably, the main component is polylactic acid, preferably 60% by weight or more, more preferably 80% by weight or more of the whole biodegradable polyester recovered product. The polylactic acid can be applied to various polylactic acids such as poly L-lactic acid, poly D-lactic acid, racemic polylactic acid, a mixture of poly L-lactic acid and poly D-lactic acid, and a polylactic acid stereocomplex polymer. Furthermore, since the biodegradable polyester recovered material mainly refers to a material once collected as a product in the market, it contains various different materials in addition to the biodegradable polyester. Examples of the different materials include polyolefins such as polyethylene, polypropylene, and polyvinyl chloride, non-biodegradable aliphatic polyesters, aromatic polyesters, polyamides, paper, earth and sand, dust, metals, residual catalysts, and wood. Can be mentioned. Furthermore, in the method of the present invention, it is preferable that the biodegradable polyester recovered product is generally charged with a pretreatment such as washing with water and coarse pulverization to obtain a shape suitable for the depolymerization reaction. In this case, it is preferable because a foreign material that is extremely soluble in water can be removed. It is also preferable to remove foreign materials from the biodegradable polyester collection as much as possible by simple mechanical or physical means before and / or after this pretreatment. For example, there are a method of removing a material that can be visually discriminated from a different material, or a method of removing a metal attracted to the magnet using a magnet.
本発明の実施方法は、生分解性ポリエステルと水を用いて解重合反応を行う。解重合反応については、生分解性ポリエステル回収物の性状に特に限定されることはなく、その生分解性ポリエステル回収物の性状によって、任意に時間及び水の量等を調整することができる。また解重合反応は回分式又は連続式いずれも採用可能である。 The implementation method of this invention performs a depolymerization reaction using biodegradable polyester and water. The depolymerization reaction is not particularly limited to the properties of the biodegradable polyester recovery product, and the time and the amount of water can be arbitrarily adjusted according to the properties of the biodegradable polyester recovery product. The depolymerization reaction can be either batchwise or continuous.
更に本発明においては前記生分解性ポリエステル回収物を８０℃〜３００℃の温度下で解重合反応を行う必要があり、生分解性ポリエステル回収物に対して５重量倍以下の水を用いて解重合反応を行うことが好ましい。解重合生成物として生分解性ポリエステルのモノマー、生分解性ポリエステルのモノマー及びオリゴマーの混合物、又は生分解性ポリエステルのオリゴマーとして回収する。オリゴマーは重合度の異なる混合物であってもよい。他にラクチドなどを含むような条件で解重合反応を行っても良い。 Furthermore, in the present invention, the biodegradable polyester recovered product needs to be subjected to a depolymerization reaction at a temperature of 80 ° C. to 300 ° C., and the biodegradable polyester recovered product is dissolved using 5 times by weight or less of water. It is preferable to perform a polymerization reaction. The depolymerized product is recovered as a biodegradable polyester monomer, a mixture of biodegradable polyester monomers and oligomers, or an oligomer of biodegradable polyester. The oligomer may be a mixture having different degrees of polymerization. In addition, the depolymerization reaction may be performed under conditions that include lactide and the like.
解重合反応において、生分解性ポリエステル回収物は水中において反応温度は、８０℃〜３００℃、好ましくは１００℃〜２８０℃、更に好ましくは１５０℃〜２５０℃である。反応温度が３００℃より高くなると、乳酸からの有効成分以外の他の物質への分解が更に進み有効成分の回収率が低下する。一方、温度が８０℃より低いと、解重合反応の速度が極端に遅くなり、その分反応器を大型にせざるを得ず、経済的な効果が少なくなる。あるいは非常に長い解重合反応時間を要するようになる。 In the depolymerization reaction, the biodegradable polyester recovered product has a reaction temperature in water of 80 ° C to 300 ° C, preferably 100 ° C to 280 ° C, more preferably 150 ° C to 250 ° C. When the reaction temperature is higher than 300 ° C., the decomposition of lactic acid into other substances other than the active ingredient further proceeds and the recovery rate of the active ingredient is lowered. On the other hand, when the temperature is lower than 80 ° C., the rate of the depolymerization reaction becomes extremely slow, and the reactor must be enlarged accordingly, and the economic effect is reduced. Alternatively, a very long depolymerization reaction time is required.
反応圧力については、密閉型反応容器を使用した場合、反応温度が決まれば、おのずと水の蒸気圧付近と設定される。また、不活性ガスなどを用いて該反応温度での水の蒸気圧以上とすることや、反応器の一部を開放して該反応温度での水の蒸気圧以下とすることも可能である。
反応時間については、反応温度、反応圧力、生分解性ポリエステル回収物の性状、使用する水の量により任意に設定することが可能である。
Regarding the reaction pressure, when a sealed reaction vessel is used, if the reaction temperature is determined, the reaction pressure is naturally set around the vapor pressure of water. It is also possible to set the water vapor pressure at the reaction temperature to be equal to or higher than that using an inert gas, or to open the reactor partly to the water vapor pressure at the reaction temperature or lower. .
About reaction time, it is possible to set arbitrarily by reaction temperature, reaction pressure, the property of a biodegradable polyester recovery thing, and the quantity of the water to be used.
使用する水の量については、反応温度、反応圧力、生分解性ポリエステル回収物の性状、反応時間により任意に設定することが可能である。使用する水の量は生分解性ポリエステル回収物に対して５重量倍以下とすることが好ましく、更に好ましくは３重量倍以下である。使用する水の量が多すぎると、解重合反応生成物中の水の割合がその分多くなり、その使用する水量の分、解重合反応段階でのエネルギー使用量が増加し、生分解性ポリエステルのモノマー、オリゴマーを有効利用しようとした場合、濃縮操作を行うため含まれる水を留去する必要があり、この段階でもエネルギー使用量が増加するという問題がある。 About the quantity of the water to be used, it is possible to set arbitrarily by reaction temperature, reaction pressure, the property of biodegradable polyester recovered material, and reaction time. The amount of water used is preferably 5 times by weight or less, more preferably 3 times by weight or less based on the biodegradable polyester recovered product. If the amount of water used is too large, the proportion of water in the depolymerization reaction product will increase accordingly, and the amount of water used will increase the amount of energy used in the depolymerization reaction stage, resulting in biodegradable polyester. In the case of effectively utilizing the monomers and oligomers of the above, it is necessary to distill off the water contained in order to perform the concentration operation, and there is a problem that the amount of energy used increases even at this stage.
生分解性ポリエステル回収物を解重合反応させる際、酸または塩基などはじめとする既知の解重合反応触媒を添加することにより、反応時間を短くすることも可能である。
解重合生成物としては、特に生分解性ポリエステルがポリ乳酸の場合には、ポリ乳酸のモノマーである乳酸、乳酸の二量体であるラクチド、乳酸のオリゴマーなどの混合物からなる。該解重合反応物混合物は有効利用するため、再度ポリ乳酸へ変換することを主目的とするが、ポリ乳酸に返還する際、一旦オリゴマー及び／あるいはラクチドを経由することが好ましい。このため、解重合反応については、再度ポリ乳酸へ変換する際の変換率が十分に確保できるように、十分に解重合反応を行う必要がある。生分解性ポリエステル回収物に対する乳酸の回収率が２０ｗｔ％以上であることが好ましい。
When the biodegradable polyester recovered product is subjected to a depolymerization reaction, the reaction time can be shortened by adding a known depolymerization reaction catalyst such as an acid or a base.
When the biodegradable polyester is polylactic acid, the depolymerized product is composed of a mixture of lactic acid which is a monomer of polylactic acid, lactide which is a dimer of lactic acid, oligomer of lactic acid, and the like. The depolymerization product mixture is mainly used for conversion to polylactic acid again in order to effectively use it, but when returning to polylactic acid, it is preferable that the mixture is once passed through an oligomer and / or lactide. For this reason, about a depolymerization reaction, it is necessary to fully perform a depolymerization reaction so that the conversion rate at the time of converting again into polylactic acid can fully be ensured. The recovery rate of lactic acid with respect to the biodegradable polyester recovery product is preferably 20 wt% or more.
以下、実施例により本発明の内容を更に具体的に説明するが、本発明はこれにより何ら
限定を受けるものではない。尚実施例および比較例において「部」と称しているものは重
量部を表す。
（１）乳酸、ラクチド、オリゴマーの測定方法（ｗｔ％）
得られたポリ乳酸回収物の解重合反応物は、高速液体クロマトグラフ（カラム：島津製作所 ＵＬＴＲＯＮ ＰＳ−８０Ｈ、移動相：過塩素酸水溶液（ｐＨ２．１））によって測定し、乳酸、ラクチド、オリゴマー（２，３，４量体）の割合を求めた。
（２）光学純度の測定方法（ｗｔ％）
得られたポリ乳酸回収物の解重合反応物は、高速液体クロマトグラフ（カラム：ダイセル化学 ＣＨＩＲＡＬＰＡＫ ＭＡ（＋）、溶離液：2.0mM硫酸銅水溶液）によって測定し、Ｌ−乳酸及びＤ−乳酸の割合を求め、解重合生成物の光学純度とした。
（３）乳酸の回収率の求め方（ｍｏｌ％）
乳酸の回収率については、まずポリ乳酸回収物のポリ乳酸重量物を把握し、得られた解重合生成物中の乳酸重量部、乳酸の分子量及びポリ乳酸の単位分子量を用い、次の式にて求めた。
乳酸の収率＝（乳酸の重量部×７２）／（ポリ乳酸の重量部×９０）×１００
Hereinafter, the content of the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto. In addition, what is called "part" in an Example and a comparative example represents a weight part.
(1) Measuring method of lactic acid, lactide and oligomer (wt%)
The depolymerization reaction product of the obtained polylactic acid recovered product was measured by a high performance liquid chromatograph (column: ULTRON PS-80H, Shimadzu Corporation, mobile phase: perchloric acid aqueous solution (pH 2.1)), and lactic acid, lactide, oligomer The ratio of (2, 3, tetramer) was determined.
(2) Optical purity measurement method (wt%)
The depolymerization reaction product of the obtained polylactic acid recovered product was measured by a high performance liquid chromatograph (column: Daicel Chemical CHIRALPAK MA (+), eluent: 2.0 mM copper sulfate aqueous solution). The ratio was determined and used as the optical purity of the depolymerized product.
(3) How to determine the recovery rate of lactic acid (mol%)
Regarding the recovery rate of lactic acid, first, grasp the polylactic acid weight of the polylactic acid recovery product, use the lactic acid weight part in the obtained depolymerization product, the molecular weight of lactic acid and the unit molecular weight of polylactic acid, and use the following formula: Asked.
Yield of lactic acid = (parts by weight of lactic acid × 72) / (parts by weight of polylactic acid × 90) × 100
〔実施例１〕
ポリ乳酸回収物（Ｌ体＝９３．１％、平均分子量：１２９，０００、ラクティＴＭ９０１０（島津製作所製））１００部を、水３０部を解重合反応槽に投入し、５００ｒｐｍで攪拌下、１８０℃、約１ＭＰａＧ解重合反応条件下で１時間保持した。得られた解重合反応生成物を分析したところ、乳酸５１．３ｍｏｌ％、ポリ乳酸オリゴマー（２，３，４量体）４０．４ｍｏｌ％、ラクチド０ｍｏｌ％であった。該得られた解重合生成物を処理して、水の留去、オリゴマー化、ラクチド化及び開環重合反応を逐次実施したところ、分子量１００，０００のポリ乳酸が得られた。
[Example 1]
100 parts of polylactic acid recovered product (L-form = 93.1%, average molecular weight: 129,000, Lacty TM 9010 (manufactured by Shimadzu Corporation)), 30 parts of water were put into a depolymerization reaction tank, and stirred at 500 rpm. It was kept at 180 ° C. under about 1 MPaG depolymerization reaction conditions for 1 hour. When the obtained depolymerization reaction product was analyzed, it was 51.3 mol% lactic acid, 40.4 mol% polylactic acid oligomer (2,3,4 tetramer), and 0 mol% lactide. When the obtained depolymerization product was treated and subjected to water distillation, oligomerization, lactide formation and ring-opening polymerization reaction in succession, a polylactic acid having a molecular weight of 100,000 was obtained.
〔実施例２〕
実施例１において、水の量を５００部に変更し、同様の操作を行った。その結果、得られた解重合反応生成物を分析したところ、乳酸９６．６ｍｏｌ％、ポリ乳酸オリゴマー（２量体）０．９ｍｏｌ％、ラクチド０ｍｏｌ％であった。
[Example 2]
In Example 1, the amount of water was changed to 500 parts, and the same operation was performed. As a result, when the obtained depolymerization reaction product was analyzed, they were 96.6 mol% lactic acid, 0.9 mol% polylactic acid oligomer (dimer), and 0 mol% lactide.
〔実施例３〕
実施例１において、水の量を２０部に変更し、同様の操作を行った。その結果、得られた解重合反応生成物を分析したところ、乳酸３３．２ｍｏｌ％、ポリ乳酸オリゴマー（２量体）４４．２ｍｏｌ％、ラクチド０ｍｏｌ％であった。
Example 3
In Example 1, the amount of water was changed to 20 parts, and the same operation was performed. As a result, when the obtained depolymerization reaction product was analyzed, they were 33.2 mol% lactic acid, 44.2 mol% polylactic acid oligomer (dimer), and 0 mol% lactide.
〔実施例４〕
実施例１において、反応温度を１６０℃、反応圧力を約０．６ＭＰａＧ、反応時間を２時間に変更し、同様の操作を行った。その結果、得られた解重合反応生成物を分析したところ、乳酸５０．８ｍｏｌ％、ポリ乳酸オリゴマー（２，３，４量体）３９．２ｍｏｌ％、ラクチド０ｍｏｌ％であった。
Example 4
In Example 1, the reaction temperature was changed to 160 ° C., the reaction pressure was changed to about 0.6 MPaG, and the reaction time was changed to 2 hours. As a result, when the obtained depolymerization reaction product was analyzed, they were 50.8 mol% lactic acid, 39.2 mol% polylactic acid oligomer (2,3,4 tetramer), and 0 mol% lactide.
〔実施例５〕
実施例１において、反応温度を８０℃、反応圧力を常圧、反応時間を３日に変更し、同様の操作を行った。その結果、得られた解重合反応生成物を分析したところ、乳酸２９．２ｍｏｌ％、ポリ乳酸オリゴマー（２，３，４量体）１０．５ｍｏｌ％、ラクチド０ｍｏｌ％であった。
Example 5
In Example 1, the reaction temperature was changed to 80 ° C., the reaction pressure was changed to normal pressure, and the reaction time was changed to 3 days, and the same operation was performed. As a result, when the obtained depolymerization reaction product was analyzed, they were 29.2 mol% lactic acid, 10.5 mol% polylactic acid oligomer (2,3,4 tetramer), and 0 mol% lactide.
〔実施例６〕
実施例１において、反応温度を２５０℃、反応圧力を約２．４ＭＰａＧ、反応時間を１０分に変更し、同様の操作を行った。その結果、得られた解重合反応生成物を分析したところ、乳酸４６．１ｍｏｌ％、ポリ乳酸オリゴマー（２，３，４量体）３５．４ｍｏｌ％、ラクチド５．３ｍｏｌ％であった。
Example 6
In Example 1, the reaction temperature was changed to 250 ° C., the reaction pressure was changed to about 2.4 MPaG, and the reaction time was changed to 10 minutes. As a result, when the obtained depolymerization reaction product was analyzed, they were 46.1 mol% lactic acid, 35.4 mol% polylactic acid oligomer (2,3,4 tetramer), and 5.3 mol% lactide.
〔比較例１〕
実施例１において、反応温度を５０℃、反応圧力を常圧、反応時間を３日に変更し、同様の操作を行った。その結果、ポリ乳酸の解重合反応はほとんど進行せず、反応終了後未反応のポリ乳酸が約９０部回収された。
[Comparative Example 1]
In Example 1, the reaction temperature was changed to 50 ° C., the reaction pressure was changed to normal pressure, and the reaction time was changed to 3 days, and the same operation was performed. As a result, the polylactic acid depolymerization reaction hardly proceeded, and about 90 parts of unreacted polylactic acid was recovered after the reaction was completed.
〔比較例２〕
実施例１において、ポリ乳酸回収物を１０部、水の量を１０００部に変更し、同様の操作を行った。その結果、得られた解重合反応生成物を分析したところ、乳酸のみが得られ、９８．０ｍｏｌ％であった。乳酸は回収できたものの、実施例１と同じ解重合反応槽を用いたので、解重合反応槽の容量限界までポリ乳酸回収物と水の混合物を入れて処理しても、実施例１対比１０％の重量しかポリ乳酸回収物の処理ができなかった。また大量の水を解重合反応槽に入れたので、昇温の際に消費したエネルギーが大きく又処理に要する時間がかかったにもかかわらず、ポリ乳酸回収物の処理量は少なかった。
[Comparative Example 2]
In Example 1, the polylactic acid recovered product was changed to 10 parts and the amount of water was changed to 1000 parts, and the same operation was performed. As a result, when the obtained depolymerization reaction product was analyzed, only lactic acid was obtained, which was 98.0 mol%. Although lactic acid could be recovered, the same depolymerization reaction tank as in Example 1 was used. Therefore, even if a mixture of polylactic acid recovered and water was processed up to the capacity limit of the depolymerization reaction tank, it was compared with Example 1. Only the weight of the polylactic acid could be processed. In addition, since a large amount of water was put into the depolymerization reaction tank, the amount of polylactic acid recovered was small, despite the large energy consumed during the temperature increase and the time required for the treatment.
本発明により、生分解性ポリエステル回収物から有効成分を回収するため、生分解性ポリエステル回収物の加水分解反応を実施する際、使用するエネルギー量を増やさずに、乳酸、ラクチド、乳酸のオリゴマーなどの混合物として回収でき、その工業的な意義は大きい。特に生分解性ポリエステルがポリ乳酸である場合には、ポリ乳酸に対する今後の需要が見込まれているだけに特に期待することができる。 According to the present invention, in order to recover the active ingredient from the biodegradable polyester recovery product, lactic acid, lactide, lactic acid oligomer, etc. without increasing the amount of energy used when carrying out the hydrolysis reaction of the biodegradable polyester recovery product It can be recovered as a mixture of the above, and its industrial significance is great. In particular, when the biodegradable polyester is polylactic acid, it can be expected especially because future demand for polylactic acid is expected.
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2006045058A JP2007224113A (en) | 2006-02-22 | 2006-02-22 | Method for recovering effective components from recovered biodegradable polyester |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2006045058A JP2007224113A (en) | 2006-02-22 | 2006-02-22 | Method for recovering effective components from recovered biodegradable polyester |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2007224113A true JP2007224113A (en) | 2007-09-06 |
Family
ID=38546216
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2006045058A Pending JP2007224113A (en) | 2006-02-22 | 2006-02-22 | Method for recovering effective components from recovered biodegradable polyester |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2007224113A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009249508A (en) * | 2008-04-07 | 2009-10-29 | Kyushu Institute Of Technology | Method for oligomerizing polylactic acid product efficiently |
| JP2012523443A (en) * | 2009-04-14 | 2012-10-04 | ガラクティック・エス．エー． | Chemical recycling of PLA by alcoholysis |
| JP2012523442A (en) * | 2009-04-14 | 2012-10-04 | ガラクティック・エス．エー． | Chemical recycling of PLA by hydrolysis |
| WO2021181532A1 (en) * | 2020-03-10 | 2021-09-16 | マクセルホールディングス株式会社 | Polylactic acid decomposition method |
| IT202000017218A1 (en) * | 2020-07-15 | 2022-01-15 | Novamont Spa | REUSE IN POLYMERIZATION OF BIOPLASTICS |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07309863A (en) * | 1994-05-17 | 1995-11-28 | Japan Steel Works Ltd:The | Method for recovering lactide from polylactic acid product |
| JP2003300927A (en) * | 2002-04-12 | 2003-10-21 | Nagoya Industrial Science Research Inst | Method for forming monomer of biodegradable polyester |
| JP2005298401A (en) * | 2004-04-12 | 2005-10-27 | Toyohashi Univ Of Technology | Method for converting biodegradable polyester into monomer |
| JP2006274231A (en) * | 2005-03-30 | 2006-10-12 | Chiba Prefecture | Method for obtaining monomer of polylactic acid |
-
2006
- 2006-02-22 JP JP2006045058A patent/JP2007224113A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07309863A (en) * | 1994-05-17 | 1995-11-28 | Japan Steel Works Ltd:The | Method for recovering lactide from polylactic acid product |
| JP2003300927A (en) * | 2002-04-12 | 2003-10-21 | Nagoya Industrial Science Research Inst | Method for forming monomer of biodegradable polyester |
| JP2005298401A (en) * | 2004-04-12 | 2005-10-27 | Toyohashi Univ Of Technology | Method for converting biodegradable polyester into monomer |
| JP2006274231A (en) * | 2005-03-30 | 2006-10-12 | Chiba Prefecture | Method for obtaining monomer of polylactic acid |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009249508A (en) * | 2008-04-07 | 2009-10-29 | Kyushu Institute Of Technology | Method for oligomerizing polylactic acid product efficiently |
| JP2012523443A (en) * | 2009-04-14 | 2012-10-04 | ガラクティック・エス．エー． | Chemical recycling of PLA by alcoholysis |
| JP2012523442A (en) * | 2009-04-14 | 2012-10-04 | ガラクティック・エス．エー． | Chemical recycling of PLA by hydrolysis |
| KR101730666B1 (en) * | 2009-04-14 | 2017-04-26 | 걀락틱 에스.에이. | Chemical recycling of pla by alcoholysis |
| WO2021181532A1 (en) * | 2020-03-10 | 2021-09-16 | マクセルホールディングス株式会社 | Polylactic acid decomposition method |
| JPWO2021181532A1 (en) * | 2020-03-10 | 2021-09-16 | ||
| JP7425181B2 (en) | 2020-03-10 | 2024-01-30 | マクセル株式会社 | How to decompose polylactic acid |
| IT202000017218A1 (en) * | 2020-07-15 | 2022-01-15 | Novamont Spa | REUSE IN POLYMERIZATION OF BIOPLASTICS |
| WO2022013309A1 (en) * | 2020-07-15 | 2022-01-20 | Novamont S.P.A. | Reuse of bioplastics in polymerisation |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Tang et al. | Toward infinitely recyclable plastics derived from renewable cyclic esters | |
| Yoshioka et al. | Kinetics of hydrolysis of poly (ethylene terephthalate) powder in sulfuric acid by a modified shrinking-core model | |
| Ariffin et al. | Chemical recycling of polyhydroxyalkanoates as a method towards sustainable development | |
| KR102223614B1 (en) | Depolymerization of Polymer Including Ester Group by Polar Chemical Compounds | |
| JP5161466B2 (en) | Method for producing lactide from polylactic acid | |
| JP2007224113A (en) | Method for recovering effective components from recovered biodegradable polyester | |
| WO2004013217A1 (en) | Method of enzymatic depolymerization of polylactic acid and process for producing polylactic acid from depolymerization product | |
| JP4647413B2 (en) | Depolymerization method of biodegradable polyester | |
| JP5998224B2 (en) | Rapidly degradable polyester polymer and process for its production and use thereof | |
| WO2019053392A1 (en) | Enzymatic process for depolymerization of post-consumer poly(ethylene terephthalate) by a glycolysis reaction, process for recycling post-consumer poly(ethylene terephthalate) and recycled poly(ethylene terephthalate) | |
| JP6989612B2 (en) | Manufacturing method of alkyl lactic acid | |
| Abedsoltan | A focused review on recycling and hydrolysis techniques of polyethylene terephthalate | |
| JP2007023176A (en) | Method for depolymerizing biodegradable polyester | |
| JP4171823B2 (en) | Depolymerization of polyester using supercritical carbon dioxide and process for producing polyester from depolymerization product | |
| JP2009029757A (en) | Depolymerization method of polylactic acid | |
| CN104592024A (en) | Alcoholysis recovery method for waste polylactic acid material | |
| JP5678663B2 (en) | Method for producing 2-hydroxyisobutyric acid polymer and depolymerization method | |
| CN115073418B (en) | Zinc complex catalyst and method for depolymerizing high-regularity polylactic acid and recycling racemic lactide | |
| JP5193475B2 (en) | Method for producing lactide from polylactic acid | |
| KR20230029576A (en) | Compositions and methods for the degradation of waste polypropylene | |
| JP2005132901A (en) | Method for removing foreign material from aliphatic polyester | |
| JP2006176757A (en) | Production method for polyester | |
| JP4486561B2 (en) | Method for removing foreign materials from polylactic acid stereocomplex polymer | |
| Faisal et al. | Recycling of poly lactic acid into lactic acid with high temperature and high pressure water | |
| KR101428340B1 (en) | A method for preparing lactide using a ionic solvent |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20081028 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20101015 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20101019 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20101207 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20101228 |
|
| A711 | Notification of change in applicant |
Free format text: JAPANESE INTERMEDIATE CODE: A712 Effective date: 20110202 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20110328 |
|
| A911 | Transfer of reconsideration by examiner before appeal (zenchi) |
Free format text: JAPANESE INTERMEDIATE CODE: A911 Effective date: 20110411 |
|
| A912 | Removal of reconsideration by examiner before appeal (zenchi) |
Free format text: JAPANESE INTERMEDIATE CODE: A912 Effective date: 20110603 |
|
| RD02 | Notification of acceptance of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7422 Effective date: 20110708 |
|
| RD04 | Notification of resignation of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7424 Effective date: 20110708 |