阅读说明：本技术 一种r32废催化剂的资源化利用方法 (Resource utilization method of R32 waste catalyst ) 是由 赵恒军 张旗 闫家生 段誉 葛建飞 于 2021-09-24 设计创作，主要内容包括：本发明公开一种R32废催化剂的资源化利用方法,包括步骤：(1)R32废催化剂的分离：将R32穿孔物料压出,并通过过滤器将固体和液体分离；(2)R32废液体催化剂的回用：将(1)中分离后液体加入硬碱及干燥剂的混合物,搅拌,固液分离,液体测定其中五价锑含量后加回反应釜继续反应制备R32；(3)R32废固体催化剂的纯化：过滤器内固体中以一定流速通入二氯甲烷,洗涤,至流出二氯甲烷无色为止,取出干燥,储存备用；(4)R32废固体催化剂在核氯化中的应用：取(3)中干燥后催化剂固体,加入芳烃中,搅拌下,通氯反应,得到氯代芳烃。本发明经过对R32穿孔物料的分离处理,将其分别加入不同的反应系统,实现了对R32废催化剂的资源化利用。(The invention discloses a resource utilization method of an R32 waste catalyst, which comprises the following steps: (1) separation of R32 spent catalyst: pressing out the R32 perforated material and separating solids and liquids through a filter; (2) recycling of R32 waste liquid catalyst: adding the liquid separated in the step (1) into a mixture of hard alkali and a drying agent, stirring, carrying out solid-liquid separation, adding the liquid back to the reaction kettle after the content of pentavalent antimony in the liquid is measured, and continuously reacting to prepare R32; (3) purification of R32 spent solid catalyst: introducing dichloromethane into the solid in the filter at a certain flow rate, washing until the effluent dichloromethane is colorless, taking out, drying and storing for later use; (4) application of R32 waste solid catalyst in nuclear chlorination: and (4) adding the dried catalyst solid in the step (3) into aromatic hydrocarbon, and introducing chlorine for reaction under stirring to obtain chlorinated aromatic hydrocarbon. According to the invention, through separation treatment of the R32 perforated material, the R32 perforated material is respectively added into different reaction systems, so that resource utilization of the R32 waste catalyst is realized.)

1. A resource utilization method of R32 waste catalyst comprises the following preparation steps:

(1) separation of R32 spent catalyst: pressing out the R32 perforated material and separating solids and liquids through a filter;

(2) recycling of R32 waste liquid catalyst: adding the liquid separated in the step (1) into a mixture of hard alkali and a drying agent, stirring, carrying out solid-liquid separation, adding the liquid back to the reaction kettle after the content of pentavalent antimony in the liquid is measured, supplementing catalysts of antimony pentachloride and dichloromethane back according to a proportion, and continuing to react to prepare R32;

(3) purification of R32 spent solid catalyst: introducing dichloromethane into the solid in the filter in the step (1) at a certain flow rate, washing until the dichloromethane flowing out is colorless, taking out the solid catalyst in the filter, vacuum-drying at 100 ℃ until the catalyst is changed from black to grey, putting the catalyst into a dryer, and storing for later use;

(4) application of R32 waste solid catalyst in nuclear chlorination: and (3) adding the dried catalyst solid in the step (3) into aromatic hydrocarbon, and introducing chlorine for reaction under stirring to obtain chlorinated aromatic hydrocarbon, wherein the chemical equation of the reaction is shown as follows.

2. The resource utilization method of the R32 waste catalyst as claimed in claim 1, wherein the R32 waste catalyst comprises R32 waste liquid catalyst and R32 waste solid catalyst.

3. The method for recycling the R32 waste catalyst as claimed in claim 1, wherein the filter in step (1) is a detachable filter device.

4. The resource utilization method of the R32 waste catalyst as claimed in claim 2, wherein the R32 waste liquid catalyst is treated by using a mixture of easily separated calcium oxide and calcium hydroxide.

5. A resource utilization method of the R32 spent catalyst as claimed in claim 1, wherein the aromatic hydrocarbon is halogenated benzene, halogenated toluene, nitrohalogenated benzene, amino halogenated benzene, hydroxyl halogenated benzene, sulfo halogenated benzene, alkyl halogenated benzene or other benzene ring substituted compound.

6. The resource utilization method of the R32 spent catalyst as claimed in claim 5, wherein the nuclear chlorination reaction is a liquid phase chlorination reaction, and the nuclear chlorination reaction types are a solventless reaction type and a solvent reaction type.

7. The resource utilization method of the R32 waste catalyst as claimed in claim 6, wherein in the nuclear chlorination reaction, the addition amount of the R32 waste solid catalyst is 0.1-2% of the mass of the aromatic hydrocarbon.

8. The method for recycling the R32 waste catalyst as claimed in any one of claims 5 to 7, wherein the temperature of the nuclear chlorination reaction does not exceed the boiling point of the raw materials and the added solvent.

Technical Field

The invention relates to the field of R32 catalysts, in particular to a resource utilization method of a R32 waste catalyst.

Background

The catalyst commonly used for preparing R32 by liquid phase fluorination is antimony pentachloride which is a stronger Lewis acid. In the reaction process, antimony fluoride chloride can be generated with hydrogen fluoride to corrode the material of the reaction kettle, and once the welding position is not smooth enough or gas-liquid scouring corrosion is carried out for a long time due to the high valence state, carbon on the base body of the reaction kettle is exposed, so that the galvanic cell effect is formed, and the corrosion perforation of the reaction kettle is aggravated.

After the reaction kettle is perforated, the raw materials are generally recycled, and the waste catalyst can be subjected to harmless treatment after being hydrolyzed. This treatment method not only produces a large amount of solid waste, but also requires a large amount of precipitant, thereby producing a large amount of salt-containing wastewater. The catalyst is generally accompanied by fluorination during the use process, so the catalyst component in the R32 reaction is not simple antimony pentachloride generally, but a mixture of antimony chlorofluoride, after the galvanic reaction, the valence change generally occurs,and becomes trivalent antimony. Through the sampling analysis of the catalyst in the reaction kettle, the pentavalent antimony component in the catalyst is greatly reduced, the trivalent antimony component is greatly increased and can reach about 80 percent generally, and most of the trivalent antimony is changed into the fluorine antimony chloride with the SbCl composition_0.25F_2.75. The catalyst is insoluble in dichloromethane and is difficult to activate, which is one of the reasons why the catalytic effect is increasingly poor with the use of the catalyst. Therefore, the waste catalyst generated after the perforation of R32 is generally difficult to recycle.

In the nuclear chlorination process of aromatic hydrocarbon compounds, metal halides are generally adopted for chlorination, and among various metal halide catalysts, antimony trichloride is an excellent catalyst, has better selectivity and faster reaction rate, and is applied to nuclear chlorination reaction. However, antimony trichloride often has good solubility for chlorinated aromatic hydrocarbons, and the possibility of chlorination to generate antimony pentachloride is easy to occur in the chlorination process, so that the catalyst is usually difficult to recycle, thereby causing environmental problems of subsequent treatment. The catalyst with the perforations of R32 is basically insoluble in chlorinated aromatic hydrocarbon and less soluble in common aromatic hydrocarbon compounds due to the low content of chlorine atoms, and is hardly oxidized or chlorinated by chlorine gas, so that the catalyst is relatively easier to recycle.

According to the invention, the perforated R32 waste catalyst is separated and recovered, and is applied to the nuclear chlorination process of the aromatic hydrocarbon compound, so that the resource utilization of the dangerous solid waste catalyst can be realized, and the problem that the common nuclear chlorination catalyst cannot be recycled after being dissolved in the raw material can be solved.

Disclosure of Invention

In order to solve the technical problems, the invention provides a resource utilization method of an R32 waste catalyst, which aims to separate and recycle R32 dangerous solid wastes and apply the hazardous solid wastes to a nuclear chlorination process of aromatic hydrocarbons, so that the problem that the existing aromatic hydrocarbon nuclear chlorination catalyst is difficult to recycle can be solved, and the environmental problem caused by perforation of an R32 reaction kettle can be reduced.

In order to achieve the technical purpose, the technical scheme adopted by the invention is as follows:

a resource utilization method of R32 waste catalyst comprises the following preparation steps:

(1) separation of R32 spent catalyst: pressing out the R32 perforated material and separating solids and liquids through a filter;

(2) recycling of R32 waste liquid catalyst: adding the liquid separated in the step (1) into a mixture of hard alkali and a drying agent, stirring, carrying out solid-liquid separation, adding the liquid back to the reaction kettle after the content of pentavalent antimony in the liquid is measured, supplementing catalysts of antimony pentachloride and dichloromethane back according to a proportion, and continuing to react to prepare R32;

(3) purification of R32 spent solid catalyst: introducing dichloromethane into the solid in the filter in the step (1) at a certain flow rate, washing until the dichloromethane flowing out is colorless, taking out the solid catalyst in the filter, vacuum-drying at 100 ℃ until the catalyst is changed from black to grey, putting the catalyst into a dryer, and storing for later use;

(4) application of R32 waste solid catalyst in nuclear chlorination: and (3) adding the dried catalyst solid in the step (3) into aromatic hydrocarbon, and introducing chlorine for reaction under stirring to obtain chlorinated aromatic hydrocarbon, wherein the chemical equation of the reaction is shown as follows.

Preferably, the R32 spent catalyst comprises R32 spent liquid catalyst R32 spent solid catalyst.

Further, the filter in step (1) may be a removable filter device.

Preferably, the R32 waste liquid catalyst treatment adopts a mixture of easily separated calcium oxide and calcium hydroxide.

Preferably, the aromatic hydrocarbon is halogenated benzene, halogenated toluene, nitrohalogenated benzene, amidohalogenated benzene, hydroxyl halogenated benzene, sulfo halogenated benzene, alkyl halogenated benzene or other benzene ring substituted compounds. Preferably, the nuclear chlorination reaction is a liquid phase chlorination reaction, and can be divided into a solvent-free reaction and a solvent reaction.

Preferably, in the nuclear chlorination reaction, the adding amount of the waste solid catalyst R32 is 0.1-2% of the mass of the aromatic hydrocarbon.

Preferably, the nuclear chlorination reaction is a liquid phase chlorination reaction, and can be divided into a solvent-free reaction and a solvent reaction.

Further, the nuclear chlorination reaction temperature does not exceed the boiling points of the raw materials and the added solvent.

Compared with the prior art, the invention has the following beneficial effects:

1. the method comprises the steps of carrying out solid-liquid separation on the R32 waste catalyst, then carrying out solid-liquid treatment, treating the recovered liquid catalyst and raw materials, and returning the liquid catalyst and raw materials to the R32 reaction system again; the recovered solid catalyst is treated to carry out nuclear chlorination catalytic reaction, and the invention realizes resource utilization of the R32 waste catalyst.

2. By separating and recycling the R32 waste liquid catalyst, the raw material can be recycled, the cost is saved, and the generation of waste is reduced.

3. The R32 waste solid catalyst is used for nuclear chlorination reaction of aromatic hydrocarbon, so that the catalyst can be prevented from being dissolved in the aromatic hydrocarbon, and the problem that the common nuclear chlorination catalyst cannot be recycled after being dissolved in the raw material is solved.

Detailed Description

The invention will now be further illustrated by reference to the following examples

1. Preparation example

Separation of R32 spent catalyst

The reaction mass after perforation of R32 was pressed out through a line and passed through a removable filter unit to separate the solid catalyst from the liquid mass in the reaction mass. The liquid material enters a storage tank, then the solid in the filter is washed by dichloromethane until the dichloromethane at the outlet is colorless, and the washed dichloromethane is merged into the storage tank. Taking out the solid in the filter, placing the solid in a vacuum drying oven, vacuum drying at 100 ℃ for 24h, changing the catalyst from black to grey, collecting the catalyst in a dryer, and storing for later use.

50Kg of calcium oxide and 100Kg of calcium hydroxide are added into a reaction kettle provided with a condensing device in advance, then cooling water is sleeved, materials in a storage tank are slowly pressed into the reaction kettle, and the temperature in the reaction kettle is kept to be lower than 40 ℃. Stirring for 3h, press-filtering, pressing the liquid into a storage tank, measuring the content of antimony (calculated as antimony pentachloride) in the liquid, adding the liquid back to the reaction kettle, supplementing the catalysts of antimony pentachloride and dichloromethane in proportion, and continuing to react to prepare R32.

Example 1

Preparation of p-chlorotoluene

Into a 2L reaction vessel were charged 1000g of toluene, 6g of R32 solid catalyst and 1g of thiophenol, and the mixture was stirred. At 50 ℃, introducing chlorine gas at the speed of 0.2Kg/h, controlling the reaction temperature to be 50-60 ℃, introducing chlorine for 4h, and stopping the reaction. And removing residual hydrogen chloride and chlorine in the reaction liquid in vacuum at 60 ℃, filtering, separating the catalyst, and rectifying to obtain 244g of toluene, 710g of p-chlorotoluene, 390g of o-chlorotoluene and 17g of other impurities.

Example 2

Preparation of p-dichlorobenzene

1000g of chlorobenzene and 6g of R32 solid catalyst were put into a 2L reaction flask and stirred. At the temperature of 70 ℃, chlorine gas is introduced at the speed of 0.2Kg/h, the reaction temperature is controlled to be 70-80 ℃, chlorine is introduced for 4h, and the reaction is stopped. Residual hydrogen chloride and chlorine in the reaction liquid are removed in vacuum at 80 ℃, the reaction liquid is filtered, the catalyst is separated and rectified, and 1091g of p-dichlorobenzene, 158g of o-dichlorobenzene and m-dichlorobenzene and 18g of other impurities are obtained.

Example 3

Preparation of p-chlorophenol

Into a 2L reaction flask, 1000g of phenol, 6g of R32 solid catalyst and 1g of thiophenol were charged and stirred. At 50 ℃, introducing chlorine gas at the speed of 0.2Kg/h, controlling the reaction temperature to be 50-60 ℃, introducing chlorine for 3h, and stopping the reaction. And removing residual hydrogen chloride and chlorine in the reaction liquid in vacuum at 60 ℃, filtering, separating the catalyst, and rectifying to obtain 334g of phenol, 578g of p-chlorophenol, 310g of o-chlorophenol and 22g of other impurities.

Example 4

Preparation of 2, 4-dichlorotoluene:

into a 2L reactor, 1Kg of p-chlorotoluene and 6g of R32 solid catalyst were charged and stirred. And introducing chlorine gas at the speed of 0.2Kg/h at normal temperature, controlling the reaction temperature to be 30-40 ℃, introducing chlorine for 2h, and stopping the reaction. Residual hydrogen chloride and chlorine in the reaction liquid are removed in vacuum at 40 ℃, the reaction liquid is filtered, the catalyst is separated and rectified, and 210g of p-chlorotoluene, 696g of 2, 4-dichlorotoluene, 155g of 3, 4-dichlorotoluene and 106g of other impurities are obtained.

Example 5

Preparation of 3, 4-dichlorotrifluorotoluene

To a 2L reaction flask were added 1Kg of p-chlorotrifluoromethane, 6g of R32 solid catalyst. At the temperature of 60 ℃, chlorine gas is introduced at the speed of 0.2Kg/h, the reaction temperature is controlled to be 60-70 ℃, the chlorine is introduced for 1.5h, and the reaction is stopped. And removing residual hydrogen chloride and chlorine in the reaction liquid in vacuum at 70 ℃, filtering, separating the catalyst, recovering, and rectifying to obtain 305g of p-chlorotrifluoromethylene, 768g of 3, 4-dichlorobenzotrifluoride and 17g of other impurities.

Example 6

1Kg of p-chlorotrifluoromethane was charged into a 2L reaction flask, and R32 as a solid catalyst was recovered. At the temperature of 60 ℃, chlorine gas is introduced at the speed of 0.2Kg/h, the reaction temperature is controlled to be 60-70 ℃, the chlorine is introduced for 1.5h, and the reaction is stopped. Residual hydrogen chloride and chlorine in the reaction liquid are removed in vacuum at 70 ℃, the reaction liquid is filtered, the catalyst is separated and rectified, and 312g of p-chlorotrifluoromethylene, 759g of 3, 4-dichlorobenzotrifluoride and 17g of other impurities are obtained.

Through the implementation of the above embodiment, it is demonstrated that the waste solid catalyst recovered from R32 can be well applied to the nuclear chlorination process of aromatic hydrocarbons, is easy to recover and has good universality, and is a Lewis acid catalyst with high selectivity. The method points out a new direction for the treatment of the waste catalyst, is beneficial to the resource utilization of the similar solid catalyst, brings new economic benefit, and reduces the environmental impact and other problems brought by waste treatment.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the invention has been described in detail with reference to the foregoing illustrative embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the spirit and scope of the technical solutions of the embodiments of the present invention.