阅读说明：本技术 一种络合工艺中二价金属氯化盐的回收方法 (Method for recovering divalent metal chloride in complexing process ) 是由 孙海辉 易道明 甘欢华 易乐荣 张斌 黄辉其 熊志华 于 2021-09-27 设计创作，主要内容包括：本发明公开了一种络合工艺中二价金属氯化盐的回收方法,该方法向络合反应生成的络合物中加入有机非质子溶剂,再向络合物中加入有机质子溶剂的水溶液,加热搅拌回流后保温静置分层,下层得到二价金属氯化盐溶液,减压回收二价金属氯化盐溶液中的有机质子溶剂,得到浓缩后的二价金属氯化盐的水溶液,浓缩后的二价金属氯化盐的水溶液经过降温结晶、固液分离、过滤以及干燥后,回收二价金属氯化盐晶体。该方法能实现被络合物中组分的完全释放及二价金属氯化盐的回收再利用,工艺简单,回收率高达80％以上,且回收二价金属氯化盐再利用时不影响络合效果,降低了络合的生产成本,减轻了二价金属氯化盐排放对环境的不利影响。(Adding an organic aprotic solvent into a complex generated by a complexing reaction, adding an aqueous solution of an organic protic solvent into the complex, heating, stirring, refluxing, keeping the temperature, standing, layering, obtaining a divalent metal chloride solution on the lower layer, recovering the organic protic solvent in the divalent metal chloride solution under reduced pressure, obtaining a concentrated divalent metal chloride aqueous solution, and recovering a divalent metal chloride crystal after cooling, crystallizing, solid-liquid separating, filtering and drying the concentrated divalent metal chloride aqueous solution. The method can realize complete release of components in the complex and recycling of the divalent metal chloride, has simple process, the recovery rate is up to more than 80 percent, and the recycling of the divalent metal chloride does not influence the complexing effect, reduces the complexing production cost and lightens the adverse effect of the discharge of the divalent metal chloride on the environment.)

1. A method for recovering a divalent metal chloride salt in a complexation process, the method comprising the steps of:

adding an organic aprotic solvent into a complex containing divalent metal chloride, adding a set amount of aqueous solution of an organic protic solvent into the complex, heating, stirring, refluxing, preserving heat, standing, layering, and obtaining a divalent metal chloride solution on the lower layer;

and recovering the organic proton solvent in the divalent metal chloride solution under reduced pressure to obtain a concentrated divalent metal chloride aqueous solution, and recovering divalent metal chloride crystals after cooling crystallization, solid-liquid separation, filtration and drying of the concentrated divalent metal chloride aqueous solution.

2. The method for recovering divalent metal chloride salt in the complexing process according to claim 1, wherein the complex is prepared by:

adding a raw material containing the 3-hydroxy steroid compound, a divalent metal chloride and an organic aprotic solvent into a reaction vessel, uniformly mixing, heating to a set temperature, dropwise adding a set amount of organic protic solvent into the reaction vessel for a complex reaction, cooling to the set temperature after the reaction is finished, and performing solid-liquid separation to obtain a complex containing the 3-hydroxy steroid compound.

3. The method of claim 2, wherein the starting material containing 3-hydroxy steroid is phytosterin and its saturated form of stanol, cholesterol or ergosterol, the divalent metal chloride salt is calcium chloride or zinc chloride, the organic aprotic solvent is petroleum ether, n-hexane or ethyl acetate, and the organic protic solvent is methanol.

4. The method for recovering divalent metal chloride salt according to claim 2, wherein the ratio of the 3-hydroxy steroid compound-containing starting material to the organic aprotic solvent is 1 (1-2) (m: v).

5. The method for recovering a divalent metal chloride salt in a complexing process according to claim 2, wherein the mass ratio of the pure amount of the sterol compound in the organic protic solvent, the divalent metal chloride salt and the 3-hydroxysteroid compound-containing starting material is (0.5-1): (1-2): 2.

6. The method for recovering divalent metal chloride salt in the complexing process according to claim 2, wherein the set temperature of the complexing reaction is 45-65 ℃, the time of the complexing reaction is 1-4h, and the temperature is reduced to 20-30 ℃ after the complexing reaction is finished.

7. The method for recovering a divalent metal chloride salt according to claim 1, wherein the ratio of the amount of the organic aprotic solvent to the amount of the divalent metal chloride salt-containing complex is greater than 4:1(v: m), the amount of the organic protic solvent in the aqueous solution is equal to the amount of the solid complex in the complexation, and the mass ratio of the organic protic solvent to water in the aqueous solution of the organic protic solvent is (1-4): 1.

8. the method for recovering divalent metal chloride salt in the complexing process according to claim 1, wherein the temperature of heating, refluxing and stirring is 60-70 ℃ and the time is 1-4 h.

9. The method for recovering divalent metal chloride salt in the complexing process according to claim 1, wherein the temperature for cooling crystallization is 0-10 ℃ and the crystallization time is 6-24 h.

Technical Field

The invention relates to the technical field of metal salt recovery, in particular to a method for recovering divalent metal chloride in a complexing process.

Background

Steroids are natural chemical substances widely existing in nature, have a plurality of physiological activities such as anti-inflammation, anti-tumor, anti-osteoporosis and the like, and are currently on the market for more than 300 varieties. The 3-hydroxy steroid compound mainly comprises plant sterol and saturated form stanol thereof, animal cholesterol, ergosterol from bacteria and microorganism, and the like sterol compounds with hydroxyl group at 3-position. The phytosterol in 3-hydroxy steroid compound can be widely applied to medicine and food grade feed, and the cholesterol can be used for vitamin D₃And (4) synthesizing.

At present, the raw material for extracting the phytosterol is mainly vegetable oil deodorized distillate. Common extraction methods include solvent crystallization, complexation, saponification, distillation, adsorption, and enzymatic methods. In industry, complexation is often used to extract phytosterols and their 3-hydroxy steroids such as alkanol, cholesterol and ergosterol, wherein divalent metal chloride salts are often used as complexing agents.

In the prior art, when 3-hydroxy steroid compounds such as phytosterol and alkanol, cholesterol, ergosterol and the like are extracted by using divalent metal chloride as a complexing agent, only a complexing and decomplexing method is usually adopted, but a recycling method of the divalent metal chloride is not involved, and the discharge of a large amount of divalent metal chloride waste has great influence on water quality and soil and also causes resource waste.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a method for recovering divalent metal chloride in a complexing process, which can realize the complete release of a complexed component and the recovery and reutilization of the divalent metal chloride, has simple process and high recovery rate, does not influence the complexing effect when the recovered divalent metal chloride is reused, reduces the complexing production cost and lightens the adverse effect of the discharge of the divalent metal chloride on the environment.

In order to achieve the purpose, the invention is realized by the following technical scheme: a method for recovering a divalent metal chloride salt in a complexation process, the method comprising the steps of:

adding an organic aprotic solvent into a complex containing divalent metal chloride, adding a set amount of aqueous solution of an organic protic solvent into the complex, heating, stirring, refluxing, preserving heat, standing, layering, and obtaining a divalent metal chloride solution on the lower layer;

and recovering the organic proton solvent in the divalent metal chloride solution under reduced pressure to obtain a concentrated divalent metal chloride aqueous solution, and recovering divalent metal chloride crystals after cooling crystallization, solid-liquid separation, filtration and drying of the concentrated divalent metal chloride aqueous solution.

Further, the preparation method of the complex comprises the following steps:

adding a raw material containing the 3-hydroxy steroid compound, a divalent metal chloride and an organic aprotic solvent into a reaction vessel, uniformly mixing, heating to a set temperature, dropwise adding a set amount of organic protic solvent into the reaction vessel for a complex reaction, cooling to the set temperature after the reaction is finished, and performing solid-liquid separation to obtain a complex containing the 3-hydroxy steroid compound.

Further, the 3-hydroxy steroid compound is phytosterol and saturated forms of stanol, cholesterol or ergosterol thereof, the divalent metal chloride salt is calcium chloride or zinc chloride, the organic aprotic solvent is petroleum ether, n-hexane or ethyl acetate, and the organic protic solvent is methanol.

Furthermore, the dosage ratio of the raw material containing the 3-hydroxy steroid compound to the organic aprotic solvent is 1 (1-2) (m: v).

Furthermore, the mass ratio of the pure sterol compounds in the organic protic solvent, the divalent metal chloride salt and the raw material containing the 3-hydroxy steroid compound is (0.5-1): (1-2): 2.

Further, the temperature set for the complexation reaction is 45-65 ℃, the time for the complexation reaction is 1-4h, and the temperature is reduced to 20-30 ℃ after the complexation reaction is finished.

Further, the dosage ratio of the added organic aprotic solvent to the complex containing the divalent metal chloride salt is more than 4:1(v: m), the amount of the aqueous solution of the organic protic solvent is equal to that of the solid complex in the complexation reaction, and the mass ratio of the organic protic solvent to water in the aqueous solution of the organic protic solvent is (1-4): 1.

further, the heating reflux stirring temperature is 60-70 ℃, and the time is 1-4 h.

Furthermore, the temperature of the cooling crystallization is 0-10 ℃, and the crystallization time is 6-24 h.

Compared with the prior art, the invention has the beneficial effects that: the method comprises the steps of dissolving a raw material containing a target component and a divalent metal chloride in an aprotic organic solvent, adding a protic organic solvent for a complex reaction to obtain a specific complex, dispersing the complex in the aprotic organic solvent, adding a mixed solution of the protic organic solvent and water, stirring to dissolve and release the complexing agent, standing for layering, allowing the target active component to enter an aprotic organic solvent layer, allowing the divalent metal chloride to enter a protic organic solvent and a water layer after the divalent metal chloride is released, recovering the protic organic solvent from a lower-layer protic organic solvent aqueous solution after layering, cooling for cold separation, and drying to obtain the divalent metal chloride which can be reused. The method can realize the complete release of the complexed components and the recycling of the divalent metal chloride, has simple process and high recovery rate of more than 80 percent, does not influence the complexing effect when recycling the divalent metal chloride, reduces the complexing production cost and lightens the adverse effect of the discharge of the divalent metal chloride on the environment.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Detailed Description

The present invention may be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Example 1

A method for recovering divalent metal chloride in a complexing process comprises the following steps:

(1) and (3) complexing reaction: adding 200.0g of distillation residues of plant fatty acids (the content of phytosterol is 10.0 percent and the distillation residues comprise campesterol, stigmasterol and sitosterol), 10.0g of calcium chloride and 200mL of petroleum ether into a reaction container, starting stirring to uniformly mix the materials, heating to 45 ℃, dropwise adding 5.0g of methanol into the reactor to perform a complex reaction, cooling to 20 ℃ after the reaction is carried out for 4 hours, and carrying out solid-liquid separation to obtain 68.4g of a complex filter cake containing the phytosterol;

(2) releasing of the complex: adding 280mL of petroleum ether into the complex filter cake, then adding 68.4g of 80% methanol aqueous solution, heating, stirring and refluxing for 1h at 70 ℃, keeping the temperature, standing and layering, obtaining a calcium chloride solution at the lower layer for later use, and obtaining pure phytosterol with the content of 88.9% by washing, cooling, cold separating, crystallizing, filtering and drying the filter cake at the upper layer;

(3) and (3) recovering a complexing agent: and decompressing the lower-layer calcium chloride solution to recover methanol to obtain a concentrated calcium chloride aqueous solution, cooling and crystallizing the calcium chloride aqueous solution at 10 ℃ for 24 hours, and then performing solid-liquid separation, filtration and drying to obtain calcium chloride crystals with the recovery rate of 86.6%.

(4) The complexing agent is used mechanically: the recovered calcium chloride is used for carrying out the complex reaction test of the distillation residues of the vegetable fatty acid according to the conditions, and the recovered calcium chloride is repeatedly recycled and reused for many times, and the sterol content obtained each time is shown in the following table 1. As can be seen from Table 1, the recovery rate of calcium chloride recovered by this method is high, and the effect of reuse is not affected.

TABLE 1 recovery times and sterol content of calcium chloride

Example 2

A method for recovering divalent metal chloride in a complexing process comprises the following steps:

(1) and (3) complexing reaction: adding 200.0g of animal brain dry oil extract (with the cholesterol content of 15.9%), 24.0g of calcium chloride and 300mL of n-hexane into a reaction container, starting stirring to uniformly mix the materials, heating to 55 ℃, dropwise adding 12.0g of methanol into the reactor to perform a complex reaction, cooling to 25 ℃ after reacting for 2 hours, and performing solid-liquid separation to obtain a complex filter cake 122.0 containing cholesterol;

(2) releasing of the complex: adding 500mL of normal hexane into the complex filter cake, then adding 122.0g of 55% methanol aqueous solution, heating, stirring and refluxing for 2h at 65 ℃, preserving heat, standing and layering, obtaining a calcium chloride solution at the lower layer for later use, washing the upper layer with water, cooling, performing cold precipitation, crystallizing, filtering, and drying the filter cake to obtain pure cholesterol with the content of 84.2%;

(3) and (3) recovering a complexing agent: and (3) decompressing the lower-layer calcium chloride solution to recover methanol to obtain a concentrated calcium chloride aqueous solution, cooling and crystallizing the calcium chloride aqueous solution at 5 ℃ for 12 hours, and then performing solid-liquid separation, filtration and drying to obtain calcium chloride crystals with the recovery rate of 81.4%.

(4) The complexing agent is used mechanically: the recovered calcium chloride is used for carrying out a complex reaction test of the animal brain stem grease extract according to the conditions, and the animal brain stem grease extract is repeatedly recovered and reused for many times, wherein the content of cholesterol obtained each time is shown in the following table 2. As can be seen from Table 2, the recovery rate of calcium chloride recovered by this method is high, and the effect of reuse is not affected.

TABLE 2 recovery times and Cholesterol content of calcium chloride

Example 3

A method for recovering divalent metal chloride in a complexing process comprises the following steps:

(1) and (3) complexing reaction: adding 200.0g of tall oil pitch (containing 16.5% of phytosterol, comprising campesterol, stigmasterol, sitosterol and sitostanol), 33.0g of zinc chloride and 400mL of n-hexane into a reaction container, starting stirring to uniformly mix the materials, heating to 65 ℃, dropwise adding 16.5g of methanol into the reactor for complex reaction, reacting for 1h, cooling to 30 ℃, and performing solid-liquid separation to obtain 131.5g of a complex filter cake containing the phytosterol;

(2) releasing of the complex: adding 540mL of n-hexane into the complex filter cake, then adding 131.5g of 50% methanol aqueous solution, heating, stirring and refluxing for 4h at 60 ℃, keeping the temperature, standing and layering, obtaining zinc chloride solution at the lower layer for later use, and obtaining pure phytosterol with the content of 82.6% by washing the upper layer, cooling, cold separating, crystallizing, filtering and drying the filter cake;

(3) and (3) recovering a complexing agent: and (3) decompressing the zinc chloride solution at the lower layer to recover methanol to obtain a concentrated zinc chloride aqueous solution, cooling and crystallizing the zinc chloride aqueous solution at 0 ℃ for 6 hours, and then performing solid-liquid separation, filtration and drying to obtain zinc chloride crystals with the recovery rate of 80.7%.

(4) The complexing agent is used mechanically: the recovered zinc chloride is used for carrying out a complexing reaction test of tall oil pitch according to the conditions, and the tall oil pitch is repeatedly recovered and reused for many times, wherein the content of the phytosterol obtained each time is shown in the following table 3. As can be seen from Table 3, the recovery rate of zinc chloride recovered by this method is high, and the effect of reuse is not affected.

TABLE 3 recovery times and phytosterol content of zinc chloride

Example 4

A method for recovering divalent metal chloride in a complexing process comprises the following steps:

(1) and (3) complexing reaction: adding 200.0g of solid extracted after yeast fermentation (the ergosterol content is 4.9%), 10.0g of zinc chloride and 400mL of petroleum ether into a reaction container, starting stirring to uniformly mix the materials, heating to 45 ℃, dropwise adding 5.0g of methanol into the reactor to perform a complex reaction, cooling to 20 ℃ after the reaction is carried out for 2 hours, and carrying out solid-liquid separation to obtain 39.7g of a complex filter cake containing ergosterol;

(2) releasing of the complex: adding 160mL of petroleum ether into the complex filter cake, then adding 39.7g of 60% methanol aqueous solution, heating, stirring and refluxing for 2h at 70 ℃, keeping the temperature, standing and layering, obtaining a zinc chloride solution at the lower layer for later use, and obtaining pure ergosterol with the content of 82.5% by washing, cooling, cold separating, crystallizing, filtering and drying the filter cake at the upper layer;

(3) and (3) recovering a complexing agent: and (3) decompressing the zinc chloride solution at the lower layer to recover methanol to obtain a concentrated zinc chloride aqueous solution, cooling and crystallizing the zinc chloride aqueous solution at 10 ℃ for 24 hours, and then performing solid-liquid separation, filtration and drying to obtain zinc chloride crystals with the recovery rate of 81.4%.

(4) The complexing agent is used mechanically: the recovered zinc chloride is used for carrying out a complex reaction test of solid matters extracted after yeast fermentation according to the conditions, and the solid matters are repeatedly recovered and reused for many times, wherein the ergosterol content obtained each time is shown in the following table 4. As can be seen from Table 4, the recovery rate of zinc chloride recovered by this method is high, and the effect of reuse is not affected.

TABLE 4 recovery times and ergosterol content of zinc chloride

Example 5

A method for recovering divalent metal chloride in a complexing process comprises the following steps:

(1) and (3) complexing reaction: adding 200.0g of raw materials of biodiesel rectification residues (containing 7.8 percent of phytosterol and 3.2 percent of cholesterol), 22.0g of zinc chloride and 400mL of ethyl acetate into a reaction container, starting stirring to uniformly mix the materials, heating to 55 ℃, dropwise adding 11.0g of methanol into the reactor for complex reaction, cooling to 20 ℃ after reacting for 2 hours, and performing solid-liquid separation to obtain 87.9g of a complex filter cake of the phytosterol and the cholesterol;

(2) releasing of the complex: adding 360mL of ethyl acetate into the complex filter cake, then adding 87.9g of 80% methanol aqueous solution, heating, stirring and refluxing for 2h at 70 ℃, preserving heat, standing and layering, obtaining a zinc chloride solution at the lower layer for later use, and obtaining pure phytosterol and cholesterol with the total content of 86.3% by washing, cooling, cold separating, crystallizing, filtering and drying the filter cake at the upper layer;

(3) and (3) recovering a complexing agent: and (3) decompressing the zinc chloride solution at the lower layer to recover methanol to obtain a concentrated zinc chloride aqueous solution, cooling and crystallizing the zinc chloride aqueous solution at 5 ℃ for 24 hours, and then performing solid-liquid separation, filtration and drying to obtain zinc chloride crystals with the recovery rate of 83.6%.

(4) The complexing agent is used mechanically: the recovered zinc chloride is used for carrying out a complex reaction test of the distillation residues of the biodiesel according to the conditions, and is repeatedly recovered and reused for many times, and the total content of the phytosterol and the cholesterol obtained each time is shown in the following table 5. As can be seen from Table 5, the recovery rate of zinc chloride recovered by this method is high and the effect of reuse is not affected.

TABLE 5 recovery of Zinc chloride and Total phytosterol and Cholesterol content

TABLE 6 recovery of divalent Metal chloride salt under different conditions

As can be seen from the examples 1-5, the recovery rate of the divalent metal chloride salt is over 80% by adopting the process. As shown in Table 6, particularly when the ratio of the pure amount of the sterol to the amount of the divalent metal chloride salt in the 3-hydroxy steroid compound is 2:1, the content of the recovered pure sterol is the highest and can reach 88.9%, the recovery rate of the divalent metal chloride salt can reach 86.6%, and the complexing effect is not influenced when the divalent metal chloride salt is recovered for reuse, so that the production cost of complexing is reduced.

Dissolving a raw material containing a target component and a divalent metal chloride in an aprotic organic solvent, adding a protic organic solvent for a complex reaction to obtain a complex, decomplexing the complex in the aprotic organic solvent, adding a mixed solution of the protic organic solvent and water, stirring for dissolving, standing for layering, allowing the target component to enter an aprotic organic solvent layer, allowing the divalent metal chloride to enter a protic organic solvent and a water layer, performing pressure reduction on the layered lower-layer protic organic solvent aqueous solution to recover the protic organic solvent, cooling for cold separation, drying, and recovering to obtain the divalent metal chloride. The method can realize the complete release of the complexed components and the recycling of the divalent metal chloride, has simple process and high recovery rate of more than 80 percent, does not influence the complexing effect when recycling the divalent metal chloride, reduces the complexing production cost and lightens the adverse effect of the discharge of the divalent metal chloride on the environment.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, various changes and modifications can be made without departing from the spirit of the invention, and these changes and modifications are all within the scope of the invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.