CN111548333A - New method for preparing valerolactone - Google Patents

New method for preparing valerolactone Download PDF

Info

Publication number
CN111548333A
CN111548333A CN202010467374.XA CN202010467374A CN111548333A CN 111548333 A CN111548333 A CN 111548333A CN 202010467374 A CN202010467374 A CN 202010467374A CN 111548333 A CN111548333 A CN 111548333A
Authority
CN
China
Prior art keywords
valerolactone
reaction
catalyst
tetrahydrofuran
molecular sieve
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.)
Granted
Application number
CN202010467374.XA
Other languages
Chinese (zh)
Other versions
CN111548333B (en
Inventor
刘俊霞
陈景润
张伟
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shaanxi Yanchang Petroleum Group Co Ltd
Original Assignee
Shaanxi Yanchang Petroleum Group Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Shaanxi Yanchang Petroleum Group Co Ltd filed Critical Shaanxi Yanchang Petroleum Group Co Ltd
Priority to CN202010467374.XA priority Critical patent/CN111548333B/en
Publication of CN111548333A publication Critical patent/CN111548333A/en
Application granted granted Critical
Publication of CN111548333B publication Critical patent/CN111548333B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D309/00—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings
    • C07D309/16—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having one double bond between ring members or between a ring member and a non-ring member
    • C07D309/28—Heterocyclic compounds containing six-membered rings having one oxygen atom as the only ring hetero atom, not condensed with other rings having one double bond between ring members or between a ring member and a non-ring member with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
    • C07D309/30—Oxygen atoms, e.g. delta-lactones
    • 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
    • B01J29/00—Catalysts comprising molecular sieves
    • B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
    • B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
    • B01J29/70—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of types characterised by their specific structure not provided for in groups B01J29/08 - B01J29/65
    • 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
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/584—Recycling of catalysts

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Abstract

A new method for preparing valerolactone belongs to the technical field of preparing cyclic lactone by catalyzing and carbonylating with molecular sieves according to the structural similarity of raw material molecules and product molecules, and is characterized in that: tetrahydrofuran and carbon monoxide are used as raw materials, the existing structure of tetrahydrofuran molecules is fully utilized, a molecular sieve is used as a catalyst, and the valerolactone is prepared by one-step catalytic carbonylation. According to the similarity of molecular structures of tetrahydrofuran and valerolactone, the valerolactone is obtained by one-step conversion through a strategy of catalyzing carbon monoxide to increase carbon, and the high-end chemical valerolactone is obtained by one-step catalytic carbonylation reaction through an H-MOR catalyst by taking the H-MOR as a catalyst. The method has the advantages of cheap and easily-obtained raw material tetrahydrofuran, easy preparation of the molecular sieve catalyst, mild reaction conditions, simple reaction process and good industrial application prospect.

Description

New method for preparing valerolactone
Technical Field
The invention belongs to the technical field of preparing cyclic lactone by catalyzing carbonylation with a molecular sieve according to the structural similarity of a raw material molecule and a product molecule, and particularly relates to a novel method for preparing valerolactone.
Background
Valerolactone is an important starting material for organic intermediates and intermediates in the pharmaceutical industry. Has wide application in the aspects of synthetic fiber (polyester), medicine, plant protective agent and the like. Because the ring-opening polymerization reaction is easy to occur and the reaction can be carried out spontaneously, the produced high molecular polyester has the characteristic of biodegradability and can be applied to the fields of materials, medicines and the like. At present, valerolactone required by China mainly depends on import, only a few companies produce internationally, and only two companies produce domestically. In recent years, the market demand has increased due to the expansion of the use of valerolactone, and the price of valerolactone has been increasing.
With the continuous expansion of valerolactone application, especially the application prospect in the aspects of medicine and environmental protection, the future demand will be expected to increase continuously, so the existing process technology must be renovated to find a synthetic process route with mild reaction conditions and good economic benefits.
At present, many raw materials for preparing valerolactone in a laboratory mainly comprise cyclopentanone, 1, 5-pentanediol, 1, 5-glutaraldehyde, -chloropentanoic acid, 2-methyl crotonate, 1-hydroxypentanoic acid and the like. Can realize a cyclopentanone oxidation method and a 1, 5-pentanediol oxidation method which are industrially applied. The peroxyacid is used as an oxidizing agent to oxidize cyclopentanone to synthesize valerolactone, the reaction is a typical Baeyer-Villiger oxidation reaction, and in the process of synthesizing valerolactone by oxidizing cyclopentanone with peroxyacid, peroxyorganic acid is used for oxygenizing and synthesizing the cyclopentanone, the yield is high, but the peroxyacid has high toxicity and high price. The peroxyacid method is not widely used in industry because, on one hand, the reaction involves organic acid, but the corresponding organic acid brings great trouble to the later separation and treatment, thereby increasing the cost of industrial application; on the other hand, most peroxy acids are unstable, so that the peroxy acids used in laboratories are prepared at present and are generally obtained by oxidizing corresponding organic acids with high-concentration hydrogen peroxide, but the generated organic acids are difficult to recycle, and the industrial production of the organic acids is limited; also, since peroxy acids are not very stable in nature and are easily exploded at high temperatures or in the presence of severe impact, they are very inconvenient to transport and store. Many researchers continue to explore the process. However, the cyclopentanone oxidation method requires comprehensive consideration of various factors such as raw materials and reaction conditions. Later hydrogen peroxide oxidation was developed, which theoretically should produce both H2O and valerolactone, according to the reaction mechanism, but by-products of the reaction are glutaric acid and dicyclopentanone peroxide. If the yield of valerolactone is to be increased, the occurrence of side reactions and competing reactions must be suppressed, which is also a problem to be solved for industrial mass production using hydrogen peroxide as an oxidizing agent. Oxygen is an oxidant which is cheap, clean, pollution-free and safer, and the synthesis of valerolactone by using oxygen as the oxidant meets the development direction of green chemistry, but aldehyde is generally used as a co-oxidant due to poor oxidizing capability, but the price is relatively high.
Disclosure of Invention
The invention aims to solve the problems and provides a novel route for preparing valerolactone from cheap and easily available raw materials.
The novel method for preparing valerolactone takes tetrahydrofuran and carbon monoxide as raw materials, fully utilizes the existing structure of tetrahydrofuran molecules, adopts a molecular sieve as a catalyst, and prepares the valerolactone by one-step catalytic carbonylation.
Preferably, in the novel method for preparing valerolactone, the catalyst is H-MOR molecular sieve.
Preferably, in the novel method for preparing valerolactone, the catalyst is an H-MOR molecular sieve with the silicon-aluminum ratio of 5-10.
Further, in the novel method for preparing valerolactone, the catalyst H-MOR molecular sieve needs to be roasted for 6-10H at 480-550 ℃.
Preferably, the novel method for preparing valerolactone, provided by the invention, is used for evaluating the reaction of catalyzing tetrahydrofuran and carbon monoxide to prepare valerolactone by the catalyst H-MOR molecular sieve in a fixed bed reaction device.
Preferably, in the novel method for preparing valerolactone, the reaction tube of the fixed bed reaction device has the inner diameter of 10mm and the length of 40cm, the loading of the catalyst is 0.5g, and the catalyst is added in N before the reaction2Pretreating for 1h at 300 ℃ in the atmosphere, adjusting the reaction temperature and reaction pressure required by the reaction, introducing reaction raw material gas for reaction, and introducing the gas after the reaction into an online chromatograph for analysis through a heated pipeline.
Preferably, in the novel method for preparing valerolactone, the feed gas is fed with tetrahydrofuran by introducing nitrogen into a saturation tube.
Preferably, in the novel process for the preparation of valerolactone according to the invention, the reaction temperature is 100-180 ℃.
Preferably, in the novel method for preparing valerolactone, the reaction pressure is 1-5 MPa.
According to the novel method for preparing valerolactone, disclosed by the invention, according to the similarity of molecular structures of tetrahydrofuran and valerolactone, valerolactone is obtained by one-step conversion through a strategy of catalyzing carbon monoxide to increase carbon, and a high-end chemical, namely valerolactone, is obtained by one-step catalytic carbonylation reaction through an H-MOR catalyst by taking H-MOR as a catalyst. The method has the advantages of cheap and easily-obtained raw material tetrahydrofuran, easy preparation of the molecular sieve catalyst, mild reaction conditions, simple reaction process and good industrial application prospect.
Detailed Description
The novel process for the preparation of valerolactone according to the invention is illustrated in detail by the examples below.
Example one
(1) Preparing an MOR molecular sieve: adding 2.1g tetraethylammonium bromide, 4g NaOH and 8.2g NaAlO2 into 50ml water, performing ultrasonic treatment until the materials are dissolved, dropwise adding 160g silica sol, aging at room temperature, putting the materials into a stainless steel synthesis kettle, crystallizing, filtering, washing and 100 g of the obtained productoAnd C, drying to obtain the MOR molecular sieve.
(2) Weigh 1.0g of MOR molecular sieve at 550oAnd C, roasting for 6 hours to obtain the spare H-MOR molecular sieve catalyst.
(3) And (3) catalyzing the tetrahydrofuran carbonylation of the synthesized catalyst on a fixed bed reaction device to prepare valerolactone for evaluation. The inner diameter of the reaction tube of the fixed bed reaction device is 10mm, the length is 40cm, the activated H-MOR molecular sieve catalyst is loaded into the reaction tube (the loading is 0.5 g), and before the reaction, the catalyst is 300 g in the N2 atmosphereoPretreating for 1h under C, and adjusting the temperature to 150 DEGoC, starting to introduce reaction raw material gas for reaction, introducing the raw material gas into a saturated pipe by adopting nitrogen to carry tetrahydrofuran for feeding, controlling the pressure to be 1MPa, and introducing the reacted gas into an online chromatograph through a heated pipelineAnd (6) carrying out analysis.
(4) According to the results of gas chromatography detection, the conversion rate of tetrahydrofuran was 12.6%, and the selectivity of valerolactone was 94.3%.
Example two
(1) Preparing an MOR molecular sieve: the preparation process is the same as that of the first embodiment.
(2) 1.0g of MOR molecular sieve was weighed at 520oAnd C, roasting for 7 hours to obtain the spare H-MOR molecular sieve catalyst.
(3) And (3) catalyzing the tetrahydrofuran carbonylation of the synthesized catalyst on a fixed bed reaction device to prepare valerolactone for evaluation. The inner diameter of the reaction tube of the fixed bed reaction device is 10mm, the length is 40cm, the activated H-MOR molecular sieve catalyst is loaded into the reaction tube (the loading is 0.5 g), and before the reaction, the catalyst is 300 g in the N2 atmosphereoC, pretreating for 1h, and adjusting the temperature to 190oAnd C, introducing reaction raw material gas for reaction, introducing the raw material gas into a saturated pipe by adopting nitrogen to carry tetrahydrofuran for feeding, controlling the pressure to be 1.5MPa, and introducing the reacted gas into an online chromatograph for analysis through a heated pipeline.
(4) According to the results of gas chromatography, the conversion rate of tetrahydrofuran was 13.3%, and the selectivity of valerolactone was 91.8%.
EXAMPLE III
(1) Preparing an MOR molecular sieve: the preparation process is the same as that of the first embodiment.
(2) Weigh 1.0g of MOR molecular sieve at 500oAnd C, roasting for 10 hours to obtain the spare H-MOR molecular sieve catalyst.
(3) And (3) catalyzing the tetrahydrofuran carbonylation of the synthesized catalyst on a fixed bed reaction device to prepare valerolactone for evaluation. The inner diameter of the reaction tube of the fixed bed reaction device is 10mm, the length is 40cm, the activated H-MOR molecular sieve catalyst is loaded into the reaction tube (the loading is 0.5 g), and before the reaction, the catalyst is 300 g in the N2 atmosphereoC, pretreating for 1h, and adjusting the temperature to 120 DEGoC, starting to introduce reaction raw material gas for reaction, introducing the raw material gas into a saturated pipe by adopting nitrogen to carry tetrahydrofuran for feeding, controlling the pressure to be 3.5MPa, and introducing the reacted gas into an online color through a heated pipelineThe spectrometer performs the analysis.
(4) According to the detection result of gas chromatography, the conversion rate of tetrahydrofuran is 8.9%, and the selectivity of valerolactone is 96.1%.
Example four
(1) Preparing an MOR molecular sieve: the preparation process is the same as that of the first embodiment.
(2) Weighing 1.0g of MOR molecular sieve at 480oAnd C, roasting for 10 hours to obtain the spare H-MOR molecular sieve catalyst.
(3) And (3) catalyzing the tetrahydrofuran carbonylation of the synthesized catalyst on a fixed bed reaction device to prepare valerolactone for evaluation. The inner diameter of the reaction tube of the fixed bed reaction device is 10mm, the length is 40cm, the activated H-MOR molecular sieve catalyst is loaded into the reaction tube (the loading is 0.5 g), and before the reaction, the catalyst is 300 g in the N2 atmosphereoC, pretreating for 1h, and adjusting the temperature to 100oAnd C, starting to introduce reaction raw material gas for reaction, introducing the raw material gas into a saturated pipe by adopting nitrogen to carry tetrahydrofuran for feeding, controlling the pressure to be 5MPa, and introducing the reacted gas into an online chromatograph for analysis through a heated pipeline.
(4) According to the detection result of gas chromatography, the conversion rate of tetrahydrofuran is 7.4%, and the selectivity of valerolactone is 97.5%.
EXAMPLE five
(1) Preparing an MOR molecular sieve: the preparation process is the same as that of the first embodiment.
(2) Weigh 1.0g of MOR molecular sieve at 530oAnd C, roasting for 9 hours to obtain the spare H-MOR molecular sieve catalyst.
(3) And (3) catalyzing the tetrahydrofuran carbonylation of the synthesized catalyst on a fixed bed reaction device to prepare valerolactone for evaluation. The inner diameter of the reaction tube of the fixed bed reaction device is 10mm, the length is 40cm, the activated H-MOR molecular sieve catalyst is loaded into the reaction tube (the loading is 0.5 g), and before the reaction, the catalyst is 300 g in the N2 atmosphereoC, pretreating for 1h, and adjusting the temperature to 140oC, starting to introduce reaction raw material gas for reaction, introducing the raw material gas into a saturated pipe by adopting nitrogen to carry tetrahydrofuran for feeding, controlling the pressure to be 2 MPa, and introducing the reacted gas into an online color through a heated pipelineThe spectrometer performs the analysis.
(4) According to the results of gas chromatography detection, the conversion rate of tetrahydrofuran was 10.8%, and the selectivity of valerolactone was 93.9%.

Claims (9)

1. A novel method for preparing valerolactone, which is characterized by comprising the following steps: tetrahydrofuran and carbon monoxide are used as raw materials, the existing structure of tetrahydrofuran molecules is fully utilized, a molecular sieve is used as a catalyst, and the valerolactone is prepared by one-step catalytic carbonylation.
2. The novel process for the preparation of valerolactone according to claim 1, wherein: the catalyst is H-MOR molecular sieve.
3. A novel process for the preparation of valerolactone according to claim 1 or 2, wherein: the catalyst is an H-MOR molecular sieve with the silicon-aluminum ratio of 5-10.
4. A novel process for the preparation of valerolactone according to claim 3, wherein: the catalyst H-MOR molecular sieve needs to be roasted at 480-550 ℃ for 6-10H.
5. The novel process for the preparation of valerolactone according to claim 4, wherein: the catalyst H-MOR molecular sieve is used for catalyzing tetrahydrofuran and carbon monoxide on a fixed bed reaction device to carry out carbonylation to prepare valerolactone.
6. The novel process for the preparation of valerolactone according to claim 5, wherein: the inner diameter of a reaction tube of the fixed bed reaction device is 10mm, the length of the reaction tube is 40cm, the loading of the catalyst is 0.5g, and the catalyst is N before reaction2Pretreating for 1h at 300 ℃ in the atmosphere, adjusting the reaction temperature and reaction pressure required by the reaction, introducing reaction raw material gas for reaction, and introducing the gas after the reaction into an online chromatograph for analysis through a heated pipeline.
7. The novel process for the preparation of valerolactone according to claim 6, wherein: the raw material gas is introduced into a saturated tube by adopting nitrogen to carry tetrahydrofuran for feeding.
8. The novel process for the preparation of valerolactone according to claim 6, wherein: the reaction temperature is 100-180 ℃.
9. The novel process for the preparation of valerolactone according to claim 8, wherein: the reaction pressure is 1-5 MPa.
CN202010467374.XA 2020-05-28 2020-05-28 Method for preparing delta-valerolactone Active CN111548333B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010467374.XA CN111548333B (en) 2020-05-28 2020-05-28 Method for preparing delta-valerolactone

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010467374.XA CN111548333B (en) 2020-05-28 2020-05-28 Method for preparing delta-valerolactone

Publications (2)

Publication Number Publication Date
CN111548333A true CN111548333A (en) 2020-08-18
CN111548333B CN111548333B (en) 2022-08-30

Family

ID=72000761

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010467374.XA Active CN111548333B (en) 2020-05-28 2020-05-28 Method for preparing delta-valerolactone

Country Status (1)

Country Link
CN (1) CN111548333B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115353503A (en) * 2022-07-05 2022-11-18 华陆工程科技有限责任公司 Preparation method of epsilon-caprolactone

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102421821A (en) * 2009-04-08 2012-04-18 诺沃梅尔公司 Process for beta-lactone production
CN103896768A (en) * 2012-12-25 2014-07-02 中国科学院大连化学物理研究所 Method used for preparing methyl acetate
JP2016117678A (en) * 2014-12-19 2016-06-30 三菱化学株式会社 Manufacturing method of furan compound and manufacturing method of tetrahydrofuran
CN107002104A (en) * 2014-11-26 2017-08-01 维索利斯有限公司 The method converted for mevalonic acid derived from biology

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102421821A (en) * 2009-04-08 2012-04-18 诺沃梅尔公司 Process for beta-lactone production
CN103896768A (en) * 2012-12-25 2014-07-02 中国科学院大连化学物理研究所 Method used for preparing methyl acetate
CN107002104A (en) * 2014-11-26 2017-08-01 维索利斯有限公司 The method converted for mevalonic acid derived from biology
JP2016117678A (en) * 2014-12-19 2016-06-30 三菱化学株式会社 Manufacturing method of furan compound and manufacturing method of tetrahydrofuran

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
CHRISTIAN U. GR NANGER等: "Branched-regioselective hydroformylation with catalytic amounts of a reversibly bound directing group", 《ANGEW. CHEM. INT. ED.》 *
EKKEHARD BARTMANN: "Ether cleavage by activated metals. I. Cleavage of tetrahydrofuran by transition-metal activated magnesium", 《JOURNAL OF ORGANOMETALLIC CHEMISTRY》 *
KYOKO NOZAKI等: "Asymmetric hydroformylation of allylic alcohols catalyzed by Rh(I)-(R,S)-BINAPHOS", 《TETRAHEDRON LETTERS》 *
YUTAN D. Y. L. GETZLER等: "Synthesis of β-Lactones: A Highly Active and Selective Catalyst for Epoxide Carbonylation", 《J. AM. CHEM. SOC.》 *
高志: "金属加氢催化剂活性位的精细调控及其催化生物质平台分子转化性能", 《中国优秀博硕士学位论文全文数据库(博士) 工程科技Ⅰ辑》 *
魏珺楠等: "新型生物质基平台分子γ-戊内酯的应用", 《化学进展》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115353503A (en) * 2022-07-05 2022-11-18 华陆工程科技有限责任公司 Preparation method of epsilon-caprolactone
CN115353503B (en) * 2022-07-05 2023-08-25 华陆工程科技有限责任公司 Preparation method of epsilon-caprolactone

Also Published As

Publication number Publication date
CN111548333B (en) 2022-08-30

Similar Documents

Publication Publication Date Title
CN107445830B (en) Method for producing glyoxylic ester by oxidative dehydrogenation of glycolate
CN102000559A (en) Method for preparing dimethoxymethane by adopting supported niobium oxide catalyst
CN111548333B (en) Method for preparing delta-valerolactone
US11292761B2 (en) Method for directly producing methyl acetate and/or acetic acid from syngas
EP3408251B1 (en) Efficient synthesis of methacrolein from methanol and propionaldehyde
US6028221A (en) Catalyst systems for the one step gas phase production of acetic acid from ethylene and methods of making and using the same
CN111484464B (en) Method for preparing delta-valerolactone by catalyzing carbonylation of tetrahydrofuran
CN111848371A (en) Method for preparing aromatic ketone by oxidizing aromatic hydrocarbon with ozone
CN112209913B (en) Method for preparing adipic anhydride by catalyzing carbonylation of tetrahydrofuran
CN113968834A (en) Preparation method of 5-hydroxymethyl furoic acid
CN108129350B (en) Preparation method of 2, 4-dichlorobenzonitrile
US6403841B1 (en) Process for preparing partial oxidates of lower alcohols
CN109575036B (en) Metal hematoporphyrin diether diester compound, catalyst and preparation method thereof, and cyclohexane catalytic oxidation method
CN112851496A (en) Preparation method of p-toluic acid
CN107445828B (en) Method for synthesizing glyoxylic acid esters
CN110922385A (en) Method for preparing epsilon-caprolactone by oxidation of non-solvating cyclohexanone-benzaldehyde
SU722909A1 (en) Method of preparing 4-fluorophthaleic anhydride
US8269036B2 (en) Processes for producing an oxalate by coupling of CO
CN107445838B (en) Oxidation synthesis method of glyoxylic ester
CN111807937B (en) Method for synthesizing vinyl methyl ether by using ethylene glycol dimethyl ether
CN113480415B (en) Process for synthesizing glyoxal by hydroformylation of acrolein
KR101192576B1 (en) Continuous Preparation Method for Furfural from Xylose
JPH03115249A (en) Continuous production of organic acid ester
CN117964517A (en) New process for continuously producing oxime by fixed bed
US3647882A (en) Process for the manufacture of acetyldehyde from vinyl acetate

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant