阅读说明：本技术 一种二酰基类过氧化物废料的处理方法 (Treatment method of diacyl peroxide waste ) 是由 应立 应志耀 于 2019-09-25 设计创作，主要内容包括：本发明涉及有机过氧化物处理技术领域,尤其涉及一种二酰基类过氧化物废料的处理方法。本发明利用表面活性剂可提高二酰基类过氧化物废料的分散效果,更利于废料中的二酰基类过氧化物和水合肼的反应,使得反应更加充分,采用本发明的方法可以处理严重污染的二酰基类过氧化物,针对二酰基类过氧化物含量为20～25wt.％的废料仍具有很好的处理效果,本发明处理后的产物为氮气、二氯苯甲酸和氯化钠,氮气在空气中大量存在,无污染；二氯苯甲酸和氯化钠可以回收再利用。本发明的处理方法对于环境无污染,安全环保。(The invention relates to the technical field of organic peroxide treatment, in particular to a treatment method of diacyl peroxide waste. The method can improve the dispersion effect of the diacyl peroxide waste by utilizing the surfactant, is more beneficial to the reaction of diacyl peroxide and hydrazine hydrate in the waste, and ensures that the reaction is more sufficient, can treat the diacyl peroxide with serious pollution by adopting the method, still has good treatment effect on the waste with the diacyl peroxide content of 20-25 wt.%, and the treated products are nitrogen, dichlorobenzoic acid and sodium chloride, and the nitrogen exists in the air in a large amount and is pollution-free; dichlorobenzoic acid and sodium chloride can be recycled. The treatment method disclosed by the invention is pollution-free, safe and environment-friendly.)

1. A method for treating diacyl peroxide waste, which is characterized by comprising the following steps:

(1) mixing water, sodium hydroxide, hydrazine hydrate, a surfactant and diacyl peroxide waste to perform a first oxidation-reduction reaction to obtain a first mixture;

(2) mixing the first mixture with hydrogen peroxide, and carrying out a second redox reaction to obtain a second mixture;

(3) sequentially carrying out thermal decomposition, cooling and first solid-liquid separation on the second mixture to obtain filter residue and first filtrate;

(4) adding hydrochloric acid into the first filtrate until the pH value is 1-2, and performing solid-liquid separation for the second time after acid precipitation to obtain a corresponding benzoic acid crude product and a second filtrate;

(5) and adding an alkaline solution of sodium ions into the second filtrate for acid-base neutralization, and performing solid-liquid separation for the third time after evaporation concentration to obtain a solid material sodium chloride.

2. The treatment process according to claim 1, wherein the diacyl peroxide waste has a diacyl peroxide content of 20 to 25 wt.%; the diacyl peroxides comprise bis (2, 3-dichlorobenzoyl) peroxide, bis (2, 4-dichlorobenzoyl) peroxide, bis (2, 5-dichlorobenzoyl) peroxide, bis (2, 6-dichlorobenzoyl) peroxide, bis (3, 4-dichlorobenzoyl) peroxide, bis (3, 5-dichlorobenzoyl) peroxide or bis (4-methylbenzoyl) peroxide.

3. The process of claim 1, wherein the surfactant comprises sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, or sodium dodecyl sulfate.

4. The treatment method according to claim 1, wherein the molar ratio of the diacyl peroxide in the sodium hydroxide, the hydrazine hydrate and the diacyl peroxide waste is 4: 1 to 1.5: 2.

5. The treatment method according to claim 1, wherein the first oxidation-reduction reaction is carried out in step (1), and the amount of sodium hydroxide is 1.5 to 3.5 wt.% based on the total amount of the raw materials.

6. The treatment method according to claim 1, wherein the temperature of the first oxidation reaction in the step (1) is 30 to 70 ℃ and the time is 2 to 6 hours.

7. The treatment method according to claim 1, wherein the temperature of the second redox reaction in the step (2) is normal temperature, and the time is 0.5-2 h.

8. The treatment method according to claim 1, wherein the thermal decomposition in the step (3) is carried out at a temperature of 70 to 100 ℃ for 15 to 60 minutes.

9. The process of claim 1, wherein the alkaline solution of sodium ions in step (5) comprises a sodium hydroxide solution, a sodium carbonate solution or a sodium bicarbonate solution.

10. The treatment method according to claim 1 or 9, wherein the pH value of the system after the acid-base neutralization in the step (5) is 5-7.

Technical Field

The invention relates to the technical field of organic peroxide treatment, in particular to a treatment method of diacyl peroxide waste.

Background

Diacyl peroxides such as bis (2, 3-dichlorobenzoyl) peroxide, bis (2, 4-dichlorobenzoyl) peroxide, bis (2, 5-dichlorobenzoyl) peroxide, bis (2, 6-dichlorobenzoyl) peroxide, bis (3, 4-dichlorobenzoyl) peroxide, bis (3, 5-dichlorobenzoyl) peroxide and bis (4-methylbenzoyl) peroxide (PMBP for short) are pasty solids and are often used as vulcanizing agents, and the obtained product has high strength and good transparency. However, if the diacyl peroxide is contaminated during the kneading process of the preparation, it is difficult to find and separate the impurities from the material, which has a great influence on the subsequent production, not only the product quality, but also a fire or even an explosion may occur during the subsequent treatment. And the collected contaminated diacyl peroxide finished product cannot be sold due to unqualified quality. Or in the production process of diacyl peroxides, there are often cases where the diacyl peroxides undergo serious self-decomposition due to production accidents or long-term storage, and the decomposed diacyl peroxide waste cannot be recovered by simple treatment, thereby losing the utility value.

Disclosure of Invention

The invention aims to provide a method for treating diacyl peroxide waste, which can treat diacyl peroxide which is decomposed or seriously polluted, is safe and environment-friendly, and can recycle the treated product.

In order to achieve the above object, the present invention provides the following technical solutions:

the invention provides a method for treating diacyl peroxide waste, which comprises the following steps:

(1) mixing water, sodium hydroxide, hydrazine hydrate, a surfactant and diacyl peroxide waste to perform a first oxidation-reduction reaction to obtain a first mixture;

(2) mixing the first mixture with hydrogen peroxide, and carrying out a second redox reaction to obtain a second mixture;

(3) sequentially carrying out thermal decomposition, cooling and first solid-liquid separation on the second mixture to obtain filter residue and first filtrate;

(4) adding hydrochloric acid into the first filtrate until the pH value is 1-2, and performing solid-liquid separation for the second time after acid precipitation to obtain a corresponding benzoic acid crude product and a second filtrate;

(5) and adding an alkaline solution of sodium ions into the second filtrate for acid-base neutralization, and performing solid-liquid separation for the third time after evaporation concentration to obtain a solid material sodium chloride.

Preferably, the content of the diacyl peroxides in the diacyl peroxide waste is 20-25 wt.%; the diacyl peroxides comprise bis (2, 3-dichlorobenzoyl) peroxide, bis (2, 4-dichlorobenzoyl) peroxide, bis (2, 5-dichlorobenzoyl) peroxide, bis (2, 6-dichlorobenzoyl) peroxide, bis (3, 4-dichlorobenzoyl) peroxide, bis (3, 5-dichlorobenzoyl) peroxide or bis (4-methylbenzoyl) peroxide.

Preferably, the surfactant comprises sodium dodecylbenzene sulfonate, sodium dodecyl sulfate or sodium dodecyl sulfate.

Preferably, the molar ratio of the diacyl peroxide in the sodium hydroxide, the hydrazine hydrate and the diacyl peroxide waste is 4: 1-1.5: 2.

Preferably, in the step (1), the amount of sodium hydroxide used in the first oxidation-reduction reaction is 1.5 to 3.5 wt.% of the total amount of each raw material.

Preferably, the temperature of the first oxidation reaction in the step (1) is 30-70 ℃, and the time is 2-6 h.

Preferably, the temperature of the second redox reaction in the step (2) is normal temperature, and the time is 0.5-2 h.

Preferably, the thermal decomposition temperature in the step (3) is 70-100 ℃, and the time is 15-60 min.

Preferably, the alkaline solution of sodium ions in step (5) includes a sodium hydroxide solution, a sodium carbonate solution or a sodium bicarbonate solution.

Preferably, the pH value of the system after acid-base neutralization in the step (5) is 5-7.

The invention provides a method for treating diacyl peroxide waste, which comprises the following steps: (1) mixing water, sodium hydroxide, hydrazine hydrate, a surfactant and diacyl peroxide waste to perform a first oxidation-reduction reaction to obtain a first mixture; (2) mixing the first mixture with hydrogen peroxide, and carrying out a second redox reaction to obtain a second mixture; (3) sequentially carrying out thermal decomposition, cooling and first solid-liquid separation on the second mixture to obtain filter residue and first filtrate; (4) adding hydrochloric acid into the first filtrate until the pH value is 1-2, and performing solid-liquid separation for the second time after acid precipitation to obtain a corresponding benzoic acid crude product and a second filtrate; (5) and adding an alkaline solution of sodium ions into the second filtrate for acid-base neutralization, and performing solid-liquid separation for the third time after evaporation concentration to obtain a solid material sodium chloride.

The method can improve the dispersion effect of the diacyl peroxide waste by utilizing the surfactant, is more beneficial to the reaction of diacyl peroxide and hydrazine hydrate in the waste, and ensures that the reaction is more sufficient, can treat the diacyl peroxide with serious pollution by adopting the method, still has good treatment effect on the waste with the diacyl peroxide content of 20-25 wt.%, and the treated products are nitrogen, dichlorobenzoic acid and sodium chloride, and the nitrogen exists in the air in a large amount and is pollution-free; dichlorobenzoic acid and sodium chloride can be recycled. The treatment method disclosed by the invention is pollution-free, safe and environment-friendly.

Detailed Description

The invention provides a method for treating diacyl peroxide waste, which comprises the following steps:

(1) mixing water, sodium hydroxide, hydrazine hydrate, a surfactant and diacyl peroxide waste to perform a first oxidation-reduction reaction to obtain a first mixture;

(2) mixing the first mixture with hydrogen peroxide, and carrying out a second redox reaction to obtain a second mixture;

(3) sequentially carrying out thermal decomposition, cooling and first solid-liquid separation on the second mixture to obtain filter residue and first filtrate;

(4) adding hydrochloric acid into the first filtrate until the pH value is 1-2, and performing solid-liquid separation for the second time after acid precipitation to obtain a corresponding benzoic acid crude product and a second filtrate;

(5) and adding an alkaline solution of sodium ions into the second filtrate for acid-base neutralization, and performing solid-liquid separation for the third time after evaporation concentration to obtain a solid material sodium chloride.

The method comprises the steps of mixing water, sodium hydroxide, hydrazine hydrate, a surfactant and diacyl peroxide waste, and carrying out a first oxidation-reduction reaction to obtain a first mixture.

In the invention, the content of diacyl peroxides in the diacyl peroxide waste is preferably 20-25 wt.%; the balance is preferably silicone oil, silicone rubber, oligomers and mechanical impurities. The silicone oil preferably accounts for 35-45 wt.% of the diacyl peroxide waste; the silicone rubber preferably accounts for 5-10 wt.% of the diacyl peroxide waste; the oligomers and mechanical impurities preferably constitute 20 to 40 wt.% of the diacyl-based peroxide waste. In the present invention, the diacyl-type peroxide preferably includes bis (2, 3-dichlorobenzoyl) peroxide, bis (2, 4-dichlorobenzoyl) peroxide, bis (2, 5-dichlorobenzoyl) peroxide, bis (2, 6-dichlorobenzoyl) peroxide, bis (3, 4-dichlorobenzoyl) peroxide, bis (3, 5-dichlorobenzoyl) peroxide or bis (4-methylbenzoyl) peroxide, and more preferably bis (2, 4-dichlorobenzoyl) peroxide or bis (4-methylbenzoyl) peroxide. The source of the diacyl peroxide waste is not particularly limited in the present invention, and diacyl peroxide waste of a known source in the art can be used.

In the invention, the molar ratio of the diacyl peroxide in the sodium hydroxide, the hydrazine hydrate and the diacyl peroxide waste is preferably 4 to (1-1.5) to 2. In the oxidation-reduction reaction, the amount of sodium hydroxide is preferably 2.5 to 3.5 wt.%, more preferably 2.5 to 3.0 wt.%, based on the total amount of the raw materials. In the present invention, the sodium hydroxide is preferably used in the form of an aqueous sodium hydroxide solution; the concentration of the sodium hydroxide aqueous solution is preferably 20-32 wt.%, more preferably 25-32 wt.%. In the present invention, the hydrazine hydrate is preferably used in the form of an aqueous solution of hydrazine hydrate; the concentration of the hydrazine hydrate aqueous solution is preferably 70-85 wt.%, and more preferably 80-85 wt.%. In the present invention, the surfactant preferably includes sodium dodecylbenzene sulfonate, sodium dodecyl sulfate or sodium dodecyl sulfonate; the surfactant is preferably used in the form of an aqueous surfactant solution; the concentration of the surfactant solution is preferably 1.5-2.5 wt.%. The amount of the surfactant is not particularly limited, and the diacyl peroxide waste is preferably changed from an agglomerated state to a uniformly dispersed state in a mixed system.

In the invention, the temperature of the first oxidation-reduction reaction is preferably 30-70 ℃, and more preferably 35-60 ℃; the time is preferably 2 to 6 hours, and more preferably 2 to 4 hours. In the present invention, the first redox reaction is preferably carried out under stirring conditions. The invention has no special requirement on the stirring speed, and can ensure that the first oxidation-reduction reaction is smoothly carried out. In the first oxidation-reduction reaction process, hydrazine hydrate and uniformly dispersed diacyl peroxide are subjected to oxidation-reduction reaction in the presence of sodium hydroxide to generate corresponding sodium benzoate and nitrogen. When the diacyl peroxides are bis (2, 3-dichlorobenzoyl) peroxide, bis (2, 4-dichlorobenzoyl) peroxide, bis (2, 5-dichlorobenzoyl) peroxide, bis (2, 6-dichlorobenzoyl) peroxide, bis (3, 4-dichlorobenzoyl) peroxide, bis (3, 5-dichlorobenzoyl) peroxide and bis (4-methylbenzoyl) peroxide, the corresponding sodium benzoate is sodium 2, 3-dichlorobenzoate, sodium 2, 4-dichlorobenzoate, sodium 2, 5-dichlorobenzoate, sodium 2, 6-dichlorobenzoate, sodium 3, 4-dichlorobenzoate, sodium 3, 5-dichlorobenzoate and sodium 4-methylbenzoate, respectively.

After the first mixture is obtained, the first mixture is mixed with hydrogen peroxide to carry out a second redox reaction to obtain a second mixture.

In the invention, the mass concentration of the hydrogen peroxide is preferably 20-70 wt.%; the dosage of the hydrogen peroxide is preferably adjusted according to the amount of residual hydrazine hydrate in the solution after the hydrazine hydrate and the diacyl peroxide in the diacyl peroxide waste material react in the alkaline environment in the step (1).

In the invention, the temperature of the second redox reaction is preferably normal temperature, i.e. no additional heating or cooling is required, and is further preferably 20-40 ℃; the time of the second redox reaction is preferably 0.5-2 h. In the present invention, the second redox reaction is preferably carried out under stirring conditions. The invention has no special requirement on the stirring speed, and can ensure that the second oxidation reduction reaction is smoothly carried out. In the second oxidation reduction process, hydrogen peroxide continuously reacts with the hydrazine hydrate remained in the reaction in the step (1), the residual hydrazine hydrate in the mixed system is removed, and water and nitrogen are generated. At this time, the second mixture obtained mainly comprises water, surfactant, corresponding sodium benzoate, oligomers in hydrogen peroxide and diacyl peroxide waste, mechanical impurities, silicone oil and silicone rubber.

After the second mixture is obtained, the second mixture is subjected to thermal decomposition, cooling and first solid-liquid separation in sequence to obtain filter residue and first filtrate.

In the invention, the thermal decomposition temperature is preferably 70-100 ℃, and more preferably 80-90 ℃; the time is preferably 15 to 60min, and more preferably 15 to 30 min. In the invention, the thermal decomposition is preferably carried out under the condition of stirring, and the invention has no special requirement on the stirring speed and can ensure that the thermal decomposition reaction sequence is carried out. In the thermal decomposition process, residual hydrogen peroxide in the previous step is decomposed to generate water and oxygen.

After thermal decomposition, the present invention cools the decomposed system. In the present invention, the cooling is performed by water bath cooling, the temperature after cooling is preferably 20 ℃, and during the cooling process, insoluble substances are gradually precipitated in the system, wherein the insoluble substances are silicone oil, silicone rubber, oligomers and mechanical impurities contained in the diacyl peroxide waste. Impurities obtained by oxidation-reduction reaction of oligomers and the like formed when diacyl peroxides are subjected to self-decomposition have certain fluidity under reaction conditions, and the viscosity is increased after cooling to form solids, so that liquid-solid separation is facilitated.

After the cooling is finished, the system is subjected to first solid-liquid separation to obtain filter residue and first filtrate. In the invention, the first solid-liquid separation is preferably realized by centrifugation, the centrifugation rotating speed in the solid-liquid separation process is preferably 800-2000 rpm, and the centrifugation time is preferably 5-20 min. The main components of the obtained first filtrate are corresponding sodium benzoate, water and part of surfactant; the filter residue is silicone oil, silicone rubber, oligomer and mechanical impurities contained in the diacyl peroxide waste, and a small amount of surfactant is inevitably carried.

After the first filtrate is obtained, adding hydrochloric acid into the first filtrate until the pH value is 1-2, and after acid precipitation, performing solid-liquid separation for the second time to obtain a corresponding benzoic acid crude product and a second filtrate.

In the invention, the concentration of the hydrochloric acid is preferably 20-36 wt.%. After hydrochloric acid is added, in the process of adjusting the pH value to 1-2, corresponding sodium benzoate in the first filtrate reacts with the hydrochloric acid to generate corresponding benzoic acid and sodium nitride, and corresponding crude benzoic acid is gradually separated out. The method has no special requirement on the acid precipitation time, and no solid is precipitated. According to the invention, the pH value after hydrochloric acid is added is controlled to be 1-2, so that the corresponding benzoic acid can be ensured to be separated out, and excessive addition of hydrochloric acid is prevented. And the hydrochloric acid can avoid introducing other impurity anions into a sodium chloride production system. In the present invention, when the diacyl-based peroxide is bis (2, 3-dichlorobenzoyl) peroxide, bis (2, 4-dichlorobenzoyl) peroxide, bis (2, 5-dichlorobenzoyl) peroxide, bis (2, 6-dichlorobenzoyl) peroxide, bis (3, 4-dichlorobenzoyl) peroxide, bis (3, 5-dichlorobenzoyl) peroxide and bis (4-methylbenzoyl) peroxide, respectively, the corresponding benzoic acid is 2, 3-dichlorobenzoic acid, 2, 4-dichlorobenzoic acid, 2, 5-dichlorobenzoic acid, 2, 6-dichlorobenzoic acid, 3, 4-dichlorobenzoic acid or 3, 5-dichlorobenzoic acid and 4-methylbenzoic acid in this order.

In the invention, the second solid-liquid separation is preferably realized by centrifugation, the centrifugation rotating speed in the solid-liquid separation process is preferably 800-2000 rpm, and the centrifugation time is preferably 5-20 min. The second filtrate obtained after solid-liquid separation mainly comprises hydrochloric acid, sodium chloride and a small amount of surfactant; the corresponding benzoic acid crude product obtained after solid-liquid separation is washed to be neutral and then dried, the purity can reach 99 percent, and the benzoic acid crude product can be used for medicines and preservatives.

After the second filtrate is obtained, adding an alkaline solution of sodium ions into the second filtrate for acid-base neutralization, evaporating and concentrating, and performing solid-liquid separation for the third time to obtain a solid material sodium chloride.

In the present invention, the alkaline solution of sodium ions preferably includes a sodium hydroxide solution, a sodium carbonate solution, or a sodium bicarbonate solution, and more preferably a sodium hydroxide solution. In the invention, the concentration of the alkaline solution of sodium ions is preferably 20-32 wt.%. In the invention, the pH value of the system after acid-base neutralization is preferably 5-7, so that salt evaporation treatment can be conveniently carried out subsequently. In the acid-base neutralization process, the residual hydrochloric acid in the previous step reacts with the alkaline solution of sodium ions to generate sodium chloride.

After acid-base neutralization, the system obtained after neutralization is evaporated and concentrated. In the invention, the solid-liquid ratio after evaporation and concentration is preferably 1kg to (0.5-2) L. In the evaporation concentration process, a large amount of sodium chloride is separated out from the system.

After the evaporation concentration is finished, the invention carries out solid-liquid separation for the third time, and the obtained solid material is sodium chloride. In the invention, the third solid-liquid separation is preferably realized by centrifugation, the centrifugation rotating speed in the solid-liquid separation process is preferably 800-2000 rpm, and the centrifugation time is preferably 5-20 min. And (3) performing solid-liquid separation to obtain a solid material, namely sodium chloride. After the third solid-liquid separation, the method preferably further comprises drying the separated sodium chloride, wherein the dried sodium chloride has high purity which can reach 98-99 wt%, and the whiteness can reach more than 80%.

It should be noted that the surfactant used in the present invention is small in amount, and in each treatment process of the filtrate, the benzoic acid is precipitated and the solid chemical obtained in the process of evaporating and crystallizing sodium chloride is carried out of the system, but the quality of the benzoic acid and the sodium chloride product is not affected.

The following examples are given to illustrate the treatment method of diacyl peroxide waste according to the present invention in detail, but they should not be construed as limiting the scope of the present invention.