阅读说明：本技术 一种二氯二苯砜釜残脱氯制备二苯砜的方法 (Method for preparing diphenyl sulfone by dechlorinating dichlorodiphenyl sulfone kettle residues ) 是由 刘佳伟 张静 朱秀全 张培恒 于 2020-06-12 设计创作，主要内容包括：一种二氯二苯砜釜残脱氯制备二苯砜的方法包括：将二氯二苯砜釜残溶于有机溶剂和水的两相中,加热,加入氧化剂,氧化处理,静置分液,有机相洗涤至中性；向有机相中加入相转移催化剂、加氢催化剂和缚酸剂,搅拌加热,通入氢气进行催化脱氯加氢至终点；体系趁热过滤,回收加氢催化剂,滤液静置分层,有机相采用热水洗涤至中性后降温析晶,过滤得到二苯砜产品,回收的加氢催化剂和有机母液循环利用；循环反应一定次数后,加氢催化剂过滤回收,有机母液通过蒸馏回收有机溶剂残留,釜残脱色重结晶回收二氯苯砜。本发明对二氯二苯砜残渣催化加氢脱氯可得到含量为97%以上的二苯砜,收率大于85%,并实现了有机母液和加氢催化剂的循环使用。(A method for preparing diphenyl sulfone by dechlorinating dichlorodiphenyl sulfone kettle residues comprises the following steps: dissolving dichlorodiphenyl sulfone kettle residues into two phases of an organic solvent and water, heating, adding an oxidant, carrying out oxidation treatment, standing for liquid separation, and washing an organic phase to be neutral; adding a phase transfer catalyst, a hydrogenation catalyst and an acid binding agent into the organic phase, stirring and heating, and introducing hydrogen to perform catalytic dechlorination and hydrogenation to a terminal point; filtering the system while the system is hot, recovering the hydrogenation catalyst, standing and layering the filtrate, washing an organic phase to be neutral by hot water, cooling and crystallizing, filtering to obtain a diphenyl sulfone product, and recycling the recovered hydrogenation catalyst and the organic mother liquor; after the cyclic reaction is carried out for a certain number of times, the hydrogenation catalyst is filtered and recovered, the organic solvent residue is recovered from the organic mother liquor through distillation, and the dichlorobenzene sulfone is recovered from the kettle residue through decoloration and recrystallization. The invention can obtain diphenyl sulfone with the content of more than 97 percent by carrying out catalytic hydrogenation and dechlorination on the dichlorodiphenyl sulfone residue, the yield is more than 85 percent, and the recycling of organic mother liquor and a hydrogenation catalyst is realized.)

1. A method for preparing diphenyl sulfone by dechlorinating dichlorodiphenyl sulfone kettle residues is characterized by comprising the following steps: the method comprises the following steps:

a. dissolving dichlorodiphenyl sulfone kettle residues in a two-phase solvent of an organic solvent and water, heating, adding an oxidant into the kettle residues for constant-temperature oxidation treatment, standing the kettle residues for layering and liquid separation while the kettle residues are hot, and washing the organic phase to be neutral by using hot water;

b. adding a phase transfer catalyst, a hydrogenation catalyst and an acid binding agent into the organic phase obtained in the step a, stirring and heating, and introducing hydrogen to perform catalytic dechlorination and hydrogenation to a terminal point;

c. filtering the system while the system is hot, recovering the hydrogenation catalyst, standing and layering the filtrate, washing an organic phase to be neutral by hot water, cooling and crystallizing, filtering to obtain a diphenyl sulfone product with the content of more than 97%, and circulating the filtered organic mother liquor for later use;

d. the hydrogenation catalyst and the organic mother liquor are used mechanically: b, feeding the filtered organic mother liquor into an oxidation process in the step a, supplementing an organic solvent, adding the dichlorodiphenyl sulfone kettle residue and an oxidant in the original proportion to perform constant-temperature oxidation reaction, and performing subsequent operation in the same step a; c, adding the hydrogenation catalyst recovered in the step c into the organic phase washed to be neutral, adding the hydrogenation catalyst according to the proportion, simultaneously adding the phase transfer catalyst and the acid binding agent in the original proportion into the catalytic hydrogenation section, and performing circular operation;

e. and (3) recovering kettle residues: after the cyclic reaction is carried out for a certain number of times, the hydrogenation catalyst is filtered and recovered, the organic solvent is recovered from the organic mother liquor through distillation, and the residual kettle residue is subjected to decoloration, recrystallization and recovery by utilizing the organic solvent and the activated carbon to obtain the diphenyl sulfone with the content of more than 97 percent.

2. The process for the dechlorination of dichlorodiphenyl sulfone kettle residues to prepare diphenyl sulfone according to claim 1, characterized in that: in the step a, dichlorodiphenyl sulfone kettle residue: organic solvent: water: oxidant = 1: (2-5): (1-2.5): (0.01-0.05), wherein the dichlorodiphenyl sulfone still residue and the oxidant are metered by mass, and the organic solvent and the water are metered by volume; the heating temperature is 50-90 ℃, the oxidation time is 0.5-2.5h, and the temperature of the washing hot water in the step a and the step c is 60-80 ℃.

3. The process for the dechlorination of dichlorodiphenyl sulfone kettle residues to prepare diphenyl sulfone according to claim 2, characterized in that: in the step a, the organic solvent is an aromatic solvent or an alkane solvent which does not contain halogen, and the oxidant is one of hydrogen peroxide, peroxyacetic acid, potassium persulfate, sodium persulfate, potassium hypochlorite, sodium hypochlorite, potassium percarbonate, sodium percarbonate, potassium perborate or sodium perborate.

4. The process for the dechlorination of dichlorodiphenyl sulfone kettle residues to prepare diphenyl sulfone according to claim 3, characterized in that: the organic solvent is one of toluene, xylene, trimethylbenzene or Isopar series alkane.

5. The process for the dechlorination of dichlorodiphenyl sulfone kettle residues to prepare diphenyl sulfone according to claim 4, characterized in that: in the step b, the heating reaction temperature is 55-85 ℃, the reaction pressure is 0-2Mpa, and the reaction time is 1.5-6 h.

6. The process for the dechlorination of dichlorodiphenyl sulfone kettle residues to prepare diphenyl sulfone according to claim 5, characterized in that: in the step b, the phase transfer catalyst is a quaternary ammonium salt catalyst, a polyether catalyst or a cyclic crown ether catalyst; the acid-binding agent is water and solid alkali which are added respectively, and the addition amount is calculated according to the concentration of the alkali liquor which is 10-40%; the hydrogenation catalyst is a noble metal catalyst; the dichlorodiphenyl sulfone kettle residue: phase transfer catalyst: solid base: hydrogenation catalyst = 1: (0.012-0.025): (3-8): (5-10), wherein the dichlorodiphenyl sulfone still residue, the phase transfer catalyst and the solid base are all metered in a molar manner, and the hydrogenation catalyst is metered in a mass manner.

7. The process for the dechlorination of dichlorodiphenyl sulfone kettle residues to prepare diphenyl sulfone according to claim 6, characterized in that: the phase transfer catalyst is one of benzyltriethylammonium chloride (TEBA), trioctylmethylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium hydrogen sulfate, chain polyethylene glycol dialkyl ether, 18 crowns 6 and 15 crowns 5; the solid alkali is sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate or potassium bicarbonate; the hydrogenation catalyst is palladium carbon, platinum carbon or skeleton nickel, and the dry content is 5%.

8. The process for the dechlorination of dichlorodiphenyl sulfone kettle residues to prepare diphenyl sulfone according to claim 7, characterized in that: in the step d, the addition amount of the hydrogenation catalyst is 5-15% of the original addition amount, the application frequency is 20-40 times, the addition amount of the organic solvent is 2-8% of the original addition amount, and the application frequency is 15-25 times.

9. The process for the dechlorination of dichlorodiphenyl sulfone kettle residues to prepare diphenyl sulfone according to claim 8, characterized in that: in the step e, the organic solvent is an aromatic solvent, an alkane solvent or an alcohol solvent, and the kettle residue: organic solvent: activated carbon = 1: (2-4): (0.1-0.5), wherein the amount of the still residue and the active carbon are measured by mass, and the amount of the organic solvent is measured by volume.

10. The process for the dechlorination of dichlorodiphenyl sulfone kettle residues to prepare diphenyl sulfone according to claim 9, characterized in that: the aromatic solvent is toluene, chlorobenzene or xylene; the alkane solvent is dichloropropane, dichloroethane or dichloromethane; the alcohol solvent is methanol or ethanol.

Technical Field

The invention relates to a preparation method of diphenyl sulfone, in particular to a method for preparing diphenyl sulfone by dechlorinating dichlorodiphenyl sulfone kettle residues.

Background

Solid waste is one of important pollution sources in chemical production, and a treatment method of the solid waste is always a difficult problem in the industry. The waste residues by-produced in chemical production are generally treated by incineration, but the waste residues containing chlorine and sulfur can generate a large amount of SOx, hydrogen sulfide, hydrogen chloride, dioxin and other substances by incineration, so the incineration treatment can cause serious secondary pollution and waste, and the recycling of the waste residues by a simple and economical mode is the most ideal treatment mode.

4, 4' -dichlorodiphenyl sulfone is an important monomer raw material for preparing engineering plastics of polysulfone and polyethersulfone, and the polysulfone and polyethersulfone are high-performance thermoplastic engineering plastics and are widely applied to industries of electric appliances, electronics, automobiles, aerospace, medicine, health and the like due to outstanding physicochemical properties of the polysulfone and polyethersulfone. Due to the special requirements of the application fields of electronic equipment, medical equipment and the like, 4' -dichlorodiphenyl sulfone with high content which is basically free from isomer is required. The method mainly comprises the steps of industrially purifying a crude product of 4, 4 ' -dichlorodiphenyl sulfone by adopting a recrystallization mode, recycling a recrystallization solvent, and finally recovering the solvent by distillation, wherein a large amount of kettle residues remained by distilling the solvent are remained, and the main component of the kettle residues is a mixture of 4, 4 ' -dichlorodiphenyl sulfone and 2, 4 ' -dichlorodiphenyl sulfone, which is called as dichlorodiphenyl sulfone kettle residues for short. 4, 4 '-dichlorodiphenyl sulfone and 2, 4' -dichlorodiphenyl sulfone are very similar in physical and chemical properties and are difficult to separate by crystallization, cryogenic crystallization or adsorption, rectification and other methods, so that most of residues are incinerated, and serious secondary pollution and resource waste are caused.

Disclosure of Invention

The invention provides a method for preparing diphenyl sulfone by dechlorinating dichlorodiphenyl sulfone kettle residues, which overcomes the defects of the prior art, and the method comprises the steps of carrying out oxidation pretreatment on the dichlorodiphenyl sulfone kettle residues, taking noble metal as a hydrogenation catalyst and hydrogen as a hydrogen source, introducing a phase transfer catalyst, carrying out hydrogenation dechlorination reaction in the presence of an acid binding agent, fully dechlorinating a dichlorodiphenyl sulfone mixture, and preparing a diphenyl sulfone industrial product which can be directly sold. The method has the advantages of high efficiency, mild reaction conditions, simple and easily controlled operation and realization of the recycling of the catalyst and the mother liquor.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a method for preparing diphenyl sulfone by dechlorinating dichlorodiphenyl sulfone kettle residues, which comprises the following steps:

a. dissolving dichlorodiphenyl sulfone kettle residues in a two-phase solvent of an organic solvent and water, heating, adding an oxidant into the kettle residues for constant-temperature oxidation treatment, standing the kettle residues for layering and liquid separation while the kettle residues are hot, and washing the organic phase to be neutral by using hot water;

b. adding a phase transfer catalyst, a hydrogenation catalyst and an acid binding agent into the organic phase obtained in the step a, stirring and heating, and introducing hydrogen to perform catalytic dechlorination and hydrogenation to a terminal point;

c. filtering the system while the system is hot, recovering the hydrogenation catalyst, standing and layering the filtrate, washing an organic phase to be neutral by hot water, cooling and crystallizing, filtering to obtain a diphenyl sulfone product with the content of more than 97%, and circulating the filtered organic mother liquor for later use;

d. the hydrogenation catalyst and the organic mother liquor are used mechanically: b, feeding the filtered organic mother liquor into an oxidation process in the step a, supplementing an organic solvent, adding the dichlorodiphenyl sulfone kettle residue and an oxidant in the original proportion to perform constant-temperature oxidation reaction, and performing subsequent operation in the same step a; c, adding the hydrogenation catalyst recovered in the step c into the organic phase washed to be neutral, adding the hydrogenation catalyst according to the proportion, simultaneously adding the phase transfer catalyst and the acid binding agent in the original proportion into the catalytic hydrogenation section, and performing circular operation;

e. and (3) recovering kettle residues: after the cyclic reaction is carried out for a certain number of times, the hydrogenation catalyst is filtered and recovered, the organic solvent is recovered from the organic mother liquor through distillation, and the residual kettle residue is subjected to decoloration, recrystallization and recovery by utilizing the organic solvent and the activated carbon to obtain the diphenyl sulfone with the content of more than 97 percent.

In the above method for preparing diphenyl sulfone by dechlorinating dichlorodiphenyl sulfone kettle residue, in step a, dichlorodiphenyl sulfone kettle residue: organic solvent: water: oxidant = 1: (2-5): (1-2.5): (0.01-0.05), wherein the dichlorodiphenyl sulfone still residue and the oxidant are metered by mass, and the organic solvent and the water are metered by volume; the heating temperature is 50-90 ℃, the oxidation time is 0.5-2.5h, and the temperature of the washing hot water in the step a and the step c is 60-80 ℃.

In the step a, the organic solvent is an aromatic solvent or an alkane solvent which does not contain halogen, and the oxidant is one of hydrogen peroxide, peracetic acid, potassium persulfate, sodium persulfate, potassium hypochlorite, sodium hypochlorite, potassium percarbonate, sodium percarbonate, potassium perborate or sodium perborate.

In the method for preparing diphenyl sulfone by dechlorinating the dichlorodiphenyl sulfone kettle residue, the organic solvent is one of toluene, xylene, trimethylbenzene or Isopar series alkane.

In the step b, the heating reaction temperature is 55-85 ℃, the reaction pressure is 0-2Mpa, and the reaction time is 1.5-6 h.

In the step b, the phase transfer catalyst is a quaternary ammonium salt catalyst, a polyether catalyst or a cyclic crown ether catalyst; the acid-binding agent is water and solid alkali which are added respectively, and the addition amount is calculated according to the concentration of the alkali liquor which is 10-40%; the hydrogenation catalyst is a noble metal catalyst; the dichlorodiphenyl sulfone kettle residue: phase transfer catalyst: solid base: hydrogenation catalyst = 1: (0.012-0.025): (3-8): (5-10), wherein the dichlorodiphenyl sulfone still residue, the phase transfer catalyst and the solid base are all metered in a molar manner, and the hydrogenation catalyst is metered in a mass manner.

In the method for preparing diphenyl sulfone by dechlorinating the dichlorodiphenyl sulfone kettle residue, the phase transfer catalyst is one of benzyltriethylammonium chloride (TEBA), trioctylmethylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium hydrogen sulfate, chain polyethylene glycol dialkyl ether, 18 crowns 6 and 15 crowns 5; the solid alkali is sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate or potassium bicarbonate; the hydrogenation catalyst is palladium carbon, platinum carbon or skeleton nickel, and the dry content is 5%.

In the method for preparing diphenyl sulfone by dechlorinating dichlorodiphenyl sulfone kettle residues, the addition amount of the hydrogenation catalyst in the step d is 5-15% of the original addition amount, the application frequency is 20-40 times, the addition amount of the organic solvent is 2-8% of the original addition amount, and the application frequency is 15-25 times.

In the above method for preparing diphenyl sulfone by dechlorinating dichlorodiphenyl sulfone kettle residue, in step e, the organic solvent is an aromatic solvent, an alkane solvent or an alcohol solvent, and the kettle residue: organic solvent: activated carbon = 1: (2-4): (0.1-0.5), wherein the amount of the still residue and the active carbon are measured by mass, and the amount of the organic solvent is measured by volume.

In the method for preparing diphenyl sulfone by dechlorinating the dichlorodiphenyl sulfone kettle residue, the aromatic solvent is toluene, chlorobenzene or xylene; the alkane solvent is dichloropropane, dichloroethane or dichloromethane; the alcohol solvent is methanol or ethanol.

The invention has the beneficial effects that: the method can be used for catalytic hydrogenation and dechlorination of dichlorodiphenyl sulfone kettle residue to obtain diphenyl sulfone with the content of more than 97 percent, the yield is more than 85 percent, and the recycling of organic mother liquor and hydrogenation catalyst is realized.

In the process for preparing 4, 4' -dichlorodiphenyl sulfone by the thionyl chloride method, the kettle residue after the crude product recrystallization mother liquor is distilled and recovered with an organic solvent contains a small amount of sulfur unsaturated valence substances, so that the noble metal catalyst is easily poisoned and deactivated, and in order to ensure the activity of the noble metal catalyst, the kettle residue is subjected to oxidation treatment before catalytic hydrodechlorination, so that the service life of the noble metal catalyst is prolonged.

The hydrogen chloride by-product produced in the reaction has a great influence on the deactivation of the hydrogenation catalyst (metal catalyst), while the selection of the solvent influences the influence of the hydrogen chloride by-product on the activity of the hydrogenation catalyst, i.e. the solubility of hydrogen chloride in different solvents directly influences the removal degree of hydrogen chloride from the surface of the hydrogenation catalyst. According to the invention, a water phase-organic phase is used as a catalytic hydrogenation solvent, a water-soluble acid binding agent is added, and a phase transfer catalyst is introduced, so that the byproduct hydrogen chloride can be rapidly removed from the surface of the hydrogenation catalyst and transferred to the water phase, and the hydrogenation catalyst has higher catalytic activity and reaction rate, thereby ensuring the high-efficiency and high-speed catalytic dechlorination.

The invention adopts the form of respectively adding water and solid alkali to replace finished alkali liquor to be directly added, and solid flake alkali is gradually dissolved along with the reaction, thereby avoiding the blockage of the reaction between the metal catalyst and reactants caused by the accumulation of negative charges on the surface of the hydrogenation catalyst due to overlarge alkalinity, and ensuring the activity of the metal catalyst.

Detailed Description

The present invention is further described below.

The invention relates to a method for preparing diphenyl sulfone by dechlorinating kettle residues after recrystallization of a crude product of dichlorodiphenyl sulfone, which comprises the following steps:

a. dissolving dichlorodiphenyl sulfone kettle residue in a two-phase solvent of an organic solvent and water, heating to 50-90 ℃, adding an oxidant into the kettle residue to perform constant-temperature oxidation treatment for 0.5-2.5h, standing the kettle residue while the kettle residue is hot, layering and separating the kettle residue, and washing the organic phase to be neutral by using hot water; dichlorodiphenyl sulfone still residue (m): organic solvent (v): water (v): oxidant (m) = 1: (2-5): (1-2.5): (0.01-0.05)

b. Adding a phase transfer catalyst into the organic phase obtained in the step a, stirring and heating to 55-85 ℃, continuously adding a hydrogenation catalyst and an acid-binding agent into the organic phase, wherein the acid-binding agent is added in a form of adding solid alkali and water respectively, the addition amount of the acid-binding agent and the water is calculated according to the concentration of alkali liquor, hydrogen is used as a hydrogen source to perform catalytic dechlorination hydrogenation for 1.5-6h to the end point, the catalytic hydrogenation pressure is controlled to be 0-2Mpa, and dichlorodiphenyl sulfone kettle residue (n): phase transfer catalyst (n): solid base (n): hydrogenation catalyst (m) = 1: (0.012-0.025): (3-8): (5-10);

c. filtering the system while the system is hot, recovering the hydrogenation catalyst, standing and layering the filtrate, washing an organic phase to be neutral by hot water, cooling and crystallizing, filtering to obtain a diphenyl sulfone product with the content of more than 97%, and circulating the filtered organic mother liquor for later use;

d. the hydrogenation catalyst and the organic mother liquor are used mechanically: b, feeding the filtered organic mother liquor into an oxidation process in the step a, supplementing an organic solvent, adding the dichlorodiphenyl sulfone kettle residue and an oxidant in the original proportion to perform constant-temperature oxidation reaction, and performing subsequent operation in the same step a;

c, adding the hydrogenation catalyst recovered in the step c into the organic phase washed to be neutral, adding the hydrogenation catalyst according to the proportion, simultaneously adding the phase transfer catalyst and the acid binding agent in the original proportion into the catalytic hydrogenation section, and performing circular operation; wherein the addition amount of the hydrogenation catalyst is 5-15% of the original addition amount, the application times are 20-40 times, the addition amount of the organic solvent is 2-8% of the original addition amount, and the application times are 15-25 times;

e. and (3) recovering kettle residues: after the cyclic reaction is carried out for a certain number of times, filtering and recovering the hydrogenation catalyst, distilling the organic mother liquor to recover the organic solvent, and distilling the residual kettle residue according to the ratio of the kettle residue (m): organic solvent (V): activated carbon (m) = 1: (2-4): (0.1-0.5) carrying out decoloration and recrystallization by using an organic solvent and activated carbon, and recovering to obtain the diphenyl sulfone with the content of more than 97%.

Step a, an oxidation procedure reaction equation:

the reaction equation of the catalytic dechlorination procedure in the step b is as follows: