A copper acetylide hydrochlorination catalyst, its preparation method and use

Abstract

The application discloses a copper acetylide hydrochlorination complex catalyst and a preparation method and application thereof, and is characterized in that the catalyst comprises 2,2'-dipyridyl-4,4'-diphosphoric acid. The ligand in the catalyst is a nitrogen-containing heterocyclic compound, so that the catalyst has good stability; the catalyst can inhibit the oxidation-reduction reaction of acetylene and divalent copper ions, and prolongs the service life; and the catalyst has the advantages of simple preparation process, high production efficiency, high atomic utilization rate, high catalyst dispersity and high catalytic conversion rate.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of catalysts, and particularly relates to a copper acetylide hydrochlorination complex catalyst for catalyzing the addition reaction of acetylene and hydrogen chloride, a preparation method and application thereof. BACKGROUND

[0002] Polyvinyl chloride (PVC) is a resin material widely used in building materials, industrial products and daily necessities. The raw material for producing polyvinyl chloride (PVC) is vinyl chloride monomer (VCM), which is obtained by polymerization reaction, and the production method is mainly divided into acetylene method and ethylene method. The former uses coal as raw material, and the latter uses petroleum as raw material. Due to the resource structure characteristics of more coal and less oil in China, it is more suitable to use acetylene method to prepare vinyl chloride monomer. The acetylene method uses acetylene and hydrogen chloride to carry out addition reaction (acetylene hydrochlorination) on a solid catalyst to prepare vinyl chloride monomer. At present, activated carbon loaded with mercury chloride is mainly used as the catalyst for the reaction in industry, but the active component of the catalyst, mercury chloride, is easy to volatilize, which has great harm to human body and environment.

[0003] In the research and application of mercury-free catalyst for acetylene hydrochlorination, the catalytically active component is mainly divided into three types: noble metal, non-metal and non-noble metal. The main noble metal catalysts are gold and ruthenium. Gold-based catalysts have high recovery rate during use, resulting in high use cost and unable to be applied on a large scale. Ruthenium-based catalysts have relatively low cost compared with gold catalysts, but still have problems of low catalytic conversion rate and high cost. Non-noble metal catalysts mainly include nitrogen-doped and boron-doped catalysts, but there is no related industrial application. Non-noble metal catalysts mainly include copper-based catalysts, which have relatively low industrial application cost.

[0004] The patent with the patent number CN201910933364.8 discloses a kind of trivalent copper catalyst and its preparation method and application in acetylene hydrochlorination reaction, nitrogen-containing heterocyclic compound and copper salt are added to trichloromethane solution and mixed to obtain the mixed solution A containing divalent copper compound;Into the obtained mixed solution A, ionic liquid is added, under the action of oxidizing agent, obtain the mixed solution B containing trivalent copper compound;The porous solid carrier is immersed in the obtained mixed solution B containing trivalent copper compound for 0.5-5h, then the solid after treatment is heated and dried under the condition of blue light irradiation, and trivalent copper catalyst is obtained;The patent with the patent number CN201910221270.8 discloses a kind of copper-based catalyst for acetylene hydrochlorination reaction to prepare vinyl chloride and its preparation and use method, the carrier of the catalyst is boron, nitrogen atom doped modified activated carbon, and the main active component is the complex formed by copper chloride and nitrogen-containing or carbonyl-containing ligand;The patent with the patent number CN202110859215.9 discloses the application of monovalent copper catalyst and its preparation method in acetylene hydrochlorination, the catalyst uses cuprous thiocyanate as the main active component, uses one or more of the compounds of potassium, barium, zinc, nickel, cobalt, silver, cerium and tin as auxiliary active component, and uses activated carbon as carrier to prepare the required catalyst after impregnation and drying. SUMMARY

[0005] The present application aims to provide a kind of acetylene hydrochlorination copper complex catalyst and its preparation method and application.The catalyst of the present application has the advantages of environmental pollution-free, good stability, high dispersity, high catalytic conversion rate, high selectivity and low cost.

[0006] The technical solution of the present application is an acetylene hydrochlorination copper complex catalyst, which comprises 2,2'-dipyridyl-4,4'-diphosphoric acid.

[0007] The catalyst is composed of copper chloride and ligand 2,2'-dipyridyl-4,4'-diphosphoric acid.

[0008] The ratio of copper chloride and ligand 2,2'-dipyridyl-4,4'-diphosphoric acid is 1-40:1-20 by weight.

[0009] Each hundred parts of the catalyst contains 1-40 parts of copper chloride, 1-20 parts of 2,2'-dipyridyl-4,4'-diphosphoric acid, and the balance is carrier activated carbon by weight.

[0010] Each hundred parts of the catalyst contains 5-25 parts of copper chloride, 6-15 parts of 2,2'-dipyridyl-4,4'-diphosphoric acid, and the balance is carrier activated carbon by weight.

[0011] The preparation method of acetylene hydrochlorination copper complex catalyst includes the following steps,

[0012] (a) adding copper chloride and 2,2'-dipyridyl-4,4'-diphosphoric acid into an aqueous solution of hydrochloric acid with pH≤1, mixing uniformly to obtain product A;

[0013] (b) mixing 1 part of product A with 10-11 parts of water by weight to dilute to obtain product B;

[0014] (c) using product B to impregnate a carrier active carbon to obtain product C;

[0015] (d) performing stepwise temperature increasing drying on product C at 50℃, 60℃, 70℃, 80℃, 90℃ and 100℃ respectively to volatilize hydrochloric acid and water to obtain the copper acetylene hydrochlorination complex catalyst.

[0016] The preparation method of the copper acetylene hydrochlorination complex catalyst described above, product C is subjected to stepwise temperature increasing drying at 50℃, 60℃, 70℃, 80℃, 90℃ and 100℃ respectively, and the catalyst is obtained after 2 hours in each stage.

[0017] Further, the application of the copper acetylene hydrochlorination complex catalyst described above, the catalyst is used for the addition reaction of acetylene and hydrogen chloride.

[0018] Further, the application of the copper acetylene hydrochlorination complex catalyst described above, characterized in that 2,2'-dipyridyl-4,4'-diphosphoric acid is used in the preparation of the copper acetylene hydrochlorination complex catalyst.

[0019] Compared with the prior art, ① the catalyst contains the ligand 2,2'-dipyridyl-4,4'-diphosphoric acid, which is a nitrogen-containing heterocyclic compound, and the ring has N atoms capable of providing rich coordination sites, which can participate in coordination as neutral molecules, and can lose protons as anions to balance the charge, at the same time, the N atoms can also act as proton donors or acceptors to form hydrogen bonds to construct supramolecular complexes, and the catalyst has good stability;

[0020] ② the copper ions can be coordinated with the N and P atoms in 2,2'-dipyridyl-4,4'-diphosphoric acid respectively, to stabilize the divalent copper ions, inhibit the redox reaction of acetylene and divalent copper ions, and prolong the service life;

[0021] ③ the catalyst preparation process is simple, the production efficiency is high, the atomic utilization rate is high, the catalyst dispersion degree is high, and the catalytic conversion rate is high.

[0022] The copper complex catalyst of the present application has a catalytic conversion rate of more than 99.5%, a selectivity of more than 99.8%, and a service life of more than 10,000 hours. Embodiment Example

[0023] The acetylene hydrochlorination copper complex catalyst comprises 2,2'-dipyridyl-4,4'-diphosphonic acid.

[0024] The catalyst is composed of copper chloride and the ligand 2,2'-dipyridyl-4,4'-diphosphonic acid.

[0025] The ratio of the copper chloride and the ligand 2,2'-dipyridyl-4,4'-diphosphonic acid is 1-40:1-20 by weight.

[0026] In each 100 parts of the catalyst, there are 1-40 parts of copper chloride, 1-20 parts of 2,2'-dipyridyl-4,4'-diphosphonic acid, and the rest is carrier activated carbon by weight.

[0027] In each 100 parts of the catalyst, there are 5-25 parts of copper chloride, 6-15 parts of 2,2'-dipyridyl-4,4'-diphosphonic acid, and the rest is carrier activated carbon by weight.

[0028] In each 100 parts of the catalyst, there are 38 parts of copper chloride, 17 parts of 2,2'-dipyridyl-4,4'-diphosphonic acid, and the rest is carrier activated carbon by weight.

[0029] The preparation method is as follows:

[0030] (a) Add copper chloride and 2,2'-dipyridyl-4,4'-diphosphonic acid into an aqueous solution of hydrochloric acid with pH≤1, mix uniformly to obtain product A;

[0031] (b) Mix 1 part of product A with 10-11 parts of water, dilute to obtain product B;

[0032] (c) Use product B to impregnate carrier activated carbon to obtain product C;

[0033] (d) Dry product C at 50℃, 60℃, 70℃, 80℃, 90℃, and 100℃ respectively in a stepwise manner, two hours for each stage, volatilize hydrochloric acid and water to obtain the acetylene hydrochlorination copper complex catalyst.

[0034] By using an aqueous solution of hydrochloric acid with pH≤1 for dissolution and then dilution, the dispersion of the catalyst can be increased.

[0035] The catalyst prepared from the raw materials in the above weight parts has an initial catalytic conversion rate of 99.6%, a selectivity of 99.9%, and a total service life of 10048 hours when used in the addition reaction of acetylene and hydrogen chloride under the conditions of acetylene space flow rate of 30h -1 Example

[0036] ​A copper complex catalyst for hydrochlorination of acetylene, the catalyst contains 36 parts of copper chloride, 18 parts of 2,2'-dipyridyl-4,4'-diphosphonic acid amine per 100 parts by weight, and the rest is carrier activated carbon.

[0037] (a) adding copper chloride and 2,2'-dipyridyl-4,4'-diphosphonic acid into an aqueous hydrochloric acid solution with pH≤1, mixing uniformly to obtain product A, and the copper chloride can be copper chloride dihydrate, which is converted according to the net weight of copper chloride;

[0038] (b) mixing 1 part of product A with 10 parts of water to obtain product B after dilution;

[0039] (c) using product B to impregnate the carrier activated carbon to obtain product C;

[0040] (d) performing stepwise temperature rising drying of product C at 50℃, 60℃, 70℃, 80℃, 90℃ and 100℃ respectively, and evaporating hydrochloric acid and water for 2 hours in each stage to obtain the copper complex catalyst for hydrochlorination of acetylene.

[0041] The catalyst prepared from the raw materials in the weight parts is used in the addition reaction of acetylene and hydrogen chloride under the conditions of acetylene space flow rate of 30h -1 -1 and acetylene to hydrogen chloride molecular ratio of 1:1.15, and the initial catalytic conversion rate is 99.8%, the selectivity is 99.9%, and the total service life is 11024 hours. Example

[0042] A copper complex catalyst for hydrochlorination of acetylene, the catalyst contains 30 parts of copper chloride, 15 parts of 2,2'-dipyridyl-4,4'-diphosphonic acid amine per 100 parts by weight, and the rest is carrier activated carbon.

[0043] (a) adding copper chloride and 2,2'-dipyridyl-4,4'-diphosphonic acid into an aqueous hydrochloric acid solution with pH≤1, mixing uniformly to obtain product A;

[0044] (b) mixing 1 part of product A with 11 parts of water to obtain product B after dilution;

[0045] (c) using product B to impregnate the carrier activated carbon to obtain product C;

[0046] (d) performing stepwise temperature rising drying of product C at 50℃, 60℃, 70℃, 80℃, 90℃ and 100℃ respectively, and evaporating hydrochloric acid and water to obtain the copper complex catalyst for hydrochlorination of acetylene.

[0047] The catalyst prepared from the raw materials in the weight parts is used in the addition reaction of acetylene and hydrogen chloride under the conditions of acetylene space flow rate of 30h -1The initial catalytic conversion rate of acetylene was 99.8%, the selectivity was 99.9%, and the total service life was 10156 hours under the condition that the acetylene and hydrogen chloride molecular ratio was 1:1.15.

Claims

1. A catalyst based on a copper hydrochloride complex of acetylene, characterized in that: The catalyst is composed of copper chloride and the ligand 2,2'-bipyridine-4,4'-bisphosphonic acid; Preparation method Includes the following steps, (a) Add copper chloride and 2,2'-bipyridine-4,4'-bisphosphoric acid to an aqueous hydrochloric acid solution with pH ≤ 1, mix well, and obtain product A; (b) Mix 1 part of product A with 10-11 parts of water by weight and dilute to obtain product B; (c) Impregnate the carrier activated carbon with product B to obtain product C; (d) Product C was dried by stepwise heating at 50℃, 60℃, 70℃, 80℃, 90℃ and 100℃ to evaporate hydrochloric acid and water, thus obtaining acetylene-copper hydroxide complex catalyst.

2. The acetylene-copper hydrochloride complex catalyst according to claim 1, characterized in that, The ratio of copper chloride to ligand 2,2'-bipyridine-4,4'-bisphosphonic acid is 1-40:1-20 by weight.

3. The acetylene-copper hydrochloride complex catalyst according to claim 2, characterized in that, By weight, every 100 parts of catalyst contains 1-40 parts of copper chloride, 1-20 parts of 2,2'-bipyridine-4,4'-bisphosphonic acid, and the remainder is activated carbon as a support.

4. The acetylene-copper hydrochloride complex catalyst according to claim 3, characterized in that, The catalyst, by weight, contains 5-25 parts of copper chloride, 6-15 parts of 2,2'-bipyridine-4,4'-bisphosphonic acid, and the balance being activated carbon support per 100 parts.

5. The acetylene-copper hydrochloride complex catalyst according to claim 1, characterized in that: Product C is a catalyst obtained by stepwise heating at 50℃, 60℃, 70℃, 80℃, 90℃, and 100℃, with each stage drying for 2 hours.

6. The application of the acetylene-copper hydrochloride complex catalyst according to any one of claims 1-5, characterized in that, Used in the addition reaction of acetylene with hydrogen chloride.