Method for recovering organic amine from catalyst production wastewater

Abstract

The invention relates to the technical field of wastewater treatment, in particular to a method for recovering organic amine from catalyst production wastewater, which comprises the steps of distillation, pH value regulation, sedimentation, solid-liquid separation and ion exchange treatment to obtain an organic amine solution. By arranging the steps of distillation, sedimentation and ion exchange, the recovery rate of the organic amine in the production wastewater can be increased, the difficulty of distillation and ion exchange operation is low, and the recovery cost is low; extra harmful substances are not generated in the organic amine recovery process, higher safety is achieved, and the harm to the environment is reduced while the recovery utilization rate of the organic amine is increased.

Description

Technical Field

[0001] The invention relates to the technical field of wastewater treatment. Background Art

[0002] Organic amine wastewater is a relatively prominent type of industrial wastewater. This type of organic amine wastewater is difficult to biodegrade, highly toxic, harmful, difficult to treat, and has an accumulation and enrichment effect. If not properly treated, it will eventually damage the ecological environment and affect human health and life. Amine substances such as aromatic amines, benzidine, triethylamine, etc. in organic amines have strong toxicity and teratogenic and carcinogenic effects on organisms and microorganisms, and have high solubility in water. They will accumulate through the food chain and eventually endanger the health of animals such as fish and humans. Organic amine substances are typical odorous pollutants with high chromaticity. If such pollutants are discharged into water bodies, they will not only make the water body stink, but the pollutants will also consume dissolved oxygen in the water. Some organic amines are highly alkaline and corrosive. If they are discharged into water bodies, they will have a greater impact on the pH value of the water body, leading to water body deterioration and ecological damage. The treatment methods of organic amine pollutants in the prior art include chemical methods, physical methods and biological methods, but the above methods are difficult to operate, have poor treatment effects and are costly. Summary of the invention

[0003] In order to overcome the technical problems of difficult operation, poor treatment effect and high cost of organic amine recovery and treatment methods in the prior art, the present invention provides a method for recovering organic amines from catalyst production wastewater.

[0004] The technical solution adopted by the present invention to achieve the above object is: a method for recovering organic amines from catalyst production wastewater, comprising the following steps:

[0005] S1: Pour the catalyst production wastewater into a distillation kettle for distillation treatment to obtain a distillate;

[0006] S2: adjusting the pH value of the remaining solution in the distillation kettle, and performing sedimentation treatment on the solution after pH adjustment;

[0007] S3: performing solid-liquid separation on the mixture after the sedimentation treatment, retaining the filtrate, and mixing the filtrate with the distillate in S1 to obtain a mixed solution;

[0008] S4: pretreating the resin in the ion resin column; filling the treated resin into the ion resin column, and using the ion resin column to perform ion exchange treatment on the mixed solution until the conductivity of the effluent during the ion exchange treatment drops to 50-100, and then the ion exchange treatment is terminated. The effluent obtained by the ion exchange treatment is an organic amine solution.

[0009] Preferably, the temperature of the distillation treatment in step S1 is 80° C. to 100° C., and the distillation time is 2 h to 4 h.

[0010] Preferably, the target pH value of the pH adjustment in step S2 is 1-4.

[0011] Preferably, in step S2, H2O2 solution is used to adjust the pH value, and the concentration of the H2O2 solution used is 5-20 mg / L.

[0012] Preferably, the solid-liquid separation in step S3 adopts a plate and frame filter press method.

[0013] Preferably, the pretreatment of the resin in the ion resin column in step S4 includes: soaking the resin in a 32% hydrochloric acid solution for 1 hour, taking it out, and rinsing it with deionized water until the pH value of the rinsed distillate is 6-8; then soaking it in a 32% sodium hydroxide solution for 0.5 hour, rinsing it with deionized water until the pH value of the rinsed distillate is 6-8, and then soaking it in a 32% hydrochloric acid solution for 1 hour to 12 hours.

[0014] Preferably, in step S4, the mass ratio of the resin to the mixed solution is 1:1.5-3.

[0015] Preferably, in the ion exchange treatment in step S4, the speed at which the mixed solution passes through the ion resin column is 2-10 g / min.

[0016] Preferably, in the process of using the ion resin column to perform ion exchange treatment on the mixed solution in step S5, if the ion resin column penetrates, an eluent is used to elute the ion resin column, and the eluent is a hydrochloric acid solution.

[0017] Preferably, the concentration of the hydrochloric acid solution is 2 mol / L.

[0018] Compared with the prior art, the present invention has the beneficial effect that, by arranging the distillation, sedimentation and ion exchange steps, the recovery rate of organic amines in production wastewater can be improved, and the distillation and ion exchange operations are relatively easy and the recovery cost is low; no additional harmful substances are generated in the process of recovering the organic amines, and the invention has higher safety, and reduces the harm to the environment while improving the recovery rate of the organic amines. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is the gas chromatogram of the solution obtained in Example 1 of the present invention.

[0020] Figure 2 It is the gas chromatogram of the solution obtained in Example 2 of the present invention. DETAILED DESCRIPTION

[0021] A specific embodiment of a method for recovering organic amines from catalyst production wastewater of the present invention comprises the following steps:

[0022] Embodiment 1:

[0023] Catalyst production wastewater comes from the production workshop, is milky white, and mainly contains tetrapropylammonium hydroxide, triethylamine, diethylamine, etc., with a pH of 10.75

[0024] S1: Pour the catalyst production wastewater into a distillation kettle for distillation treatment at a temperature of 80°C and a distillation time of 2h to obtain a distillate;

[0025] S2: Using a H2O2 solution with a concentration of 5 mg / L to adjust the pH value of the remaining solution in the distillation kettle until the pH value of the remaining solution in the distillation kettle is 1, and performing sedimentation treatment on the solution after pH adjustment;

[0026] S3: performing solid-liquid separation on the mixture after the sedimentation treatment, using a plate and frame filter press method for solid-liquid separation, retaining the filtrate, and mixing the filtrate with the distillate in S1 to obtain a mixed solution;

[0027] S4: pretreating the resin in the ion resin column, the mass ratio of the resin to the mixed solution is 1:1.5, the pretreatment includes: soaking the resin in a 32% hydrochloric acid solution for 1 hour, taking it out, rinsing it with deionized water until the pH value of the rinsed distillate is 6; soaking it in a 32% sodium hydroxide solution for 0.5 hour, rinsing it with deionized water until the pH value of the rinsed distillate is 6, and then soaking it in a 32% hydrochloric acid solution for 1 hour; filling the treated resin into the ion resin column, and using the ion resin column to perform ion exchange treatment on the mixed solution, the speed of the mixed solution passing through the ion resin column is 2g / min, until the conductivity of the effluent in the ion exchange treatment drops to 50μs / cm, and the ion exchange treatment is terminated. The effluent obtained by the ion exchange treatment is an organic amine solution, and its gas chromatogram is as shown in Figure 1 As shown, during the ion exchange treatment of the mixed solution using the ion resin column, if the ion resin column penetrates, the ion resin column is eluted with an eluent, and the eluent is a hydrochloric acid solution with a concentration of 2 mol / L.

[0028] Embodiment 2:

[0029] Catalyst production wastewater comes from the production workshop, which is clear and transparent, mainly containing tetraethylammonium hydroxide, triethylamine, diethylamine, etc., with a pH of 11.5

[0030] S1: Pour the catalyst production wastewater into a distillation kettle for distillation treatment at a temperature of 100°C and a distillation time of 4 hours to obtain a distillate;

[0031] S2: Using a 20 mg / L H2O2 solution to adjust the pH value of the remaining solution in the distillation kettle until the pH value of the remaining solution in the distillation kettle is 4, and performing sedimentation treatment on the pH-adjusted solution;

[0032] S3: performing solid-liquid separation on the mixture after the sedimentation treatment, using a plate and frame filter press method for solid-liquid separation, retaining the filtrate, and mixing the filtrate with the distillate in S1 to obtain a mixed solution;

[0033] S4: pretreating the resin in the ion resin column, the mass ratio of the resin to the mixed solution is 1:3, the pretreatment includes: soaking the resin in a 32% hydrochloric acid solution for 1 hour, taking it out, rinsing it with deionized water until the pH value of the rinsed distillate is 8; soaking it in a 32% sodium hydroxide solution for 0.5 hour, rinsing it with deionized water until the pH value of the rinsed distillate is 68, and then soaking it in a 32% hydrochloric acid solution for 12 hours; filling the treated resin into the ion resin column, and using the ion resin column to perform ion exchange treatment on the mixed solution, the speed of the mixed solution passing through the ion resin column is 10g / min, until the conductivity of the effluent in the ion exchange treatment drops to 100μs / cm, and the ion exchange treatment is terminated. The effluent obtained by the ion exchange treatment is an organic amine solution, and its gas chromatogram is as shown in Figure 2 As shown, during the ion exchange treatment of the mixed solution using the ion resin column, if the ion resin column penetrates, the ion resin column is eluted with an eluent, and the eluent is a hydrochloric acid solution with a concentration of 2 mol / L.

[0034] Embodiment 3:

[0035] Catalyst production wastewater comes from the production workshop, is milky white, and mainly contains tetrapropylammonium hydroxide, triethylamine, diethylamine, etc., with a pH of 10.75

[0036] S1: Pour the catalyst production wastewater into a distillation kettle for distillation treatment at a temperature of 90°C and a distillation time of 3h to obtain a distillate;

[0037] S2: Using a H2O2 solution with a concentration of 12 mg / L to adjust the pH value of the remaining solution in the distillation kettle until the pH value of the remaining solution in the distillation kettle is 3, and performing sedimentation treatment on the solution after pH adjustment;

[0038] S3: performing solid-liquid separation on the mixture after the sedimentation treatment, using a plate and frame filter press method for solid-liquid separation, retaining the filtrate, and mixing the filtrate with the distillate in S1 to obtain a mixed solution;

[0039] S4: pretreating the resin in the ion resin column, the mass ratio of the resin to the mixed solution is 1:2, the pretreatment includes: soaking the resin in a 32% hydrochloric acid solution for 1 hour, taking it out, rinsing it with deionized water until the pH value of the rinsed distillate is 7; soaking it in a 32% sodium hydroxide solution for 0.5 hour, rinsing it with deionized water until the pH value of the rinsed distillate is 7, and then soaking it in a 32% hydrochloric acid solution for 7 hours; filling the treated resin into the ion resin column, and using the ion resin column to perform ion exchange treatment on the mixed solution, the speed at which the mixed solution passes through the ion resin column is 6g / min, until the conductivity of the effluent in the ion exchange treatment drops to 75μs / cm, and the ion exchange treatment is terminated. The effluent obtained by the ion exchange treatment is an organic amine solution. During the ion exchange treatment of the mixed solution using the ion resin column, if the ion resin column penetrates, the ion resin column is eluted with an eluent, and the eluent is a hydrochloric acid solution with a concentration of 2mol / L.

[0040] The present invention is described by way of embodiments, and those skilled in the art will appreciate that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application belong to the protection scope of the present invention.

Claims

1. A method for recovering organic amines from catalyst production wastewater, characterized in that: The following steps are involved: S1: Pour the catalyst production wastewater into a distillation kettle for distillation treatment to obtain a distillate; S2: adjusting the pH value of the remaining solution in the distillation kettle, and performing sedimentation treatment on the solution after pH adjustment; S3: performing solid-liquid separation on the mixture after the sedimentation treatment, retaining the filtrate, and mixing the filtrate with the distillate in S1 to obtain a mixed solution; S4: pretreating the resin in the ion resin column; filling the treated resin into the ion resin column, and using the ion resin column to perform ion exchange treatment on the mixed solution until the conductivity of the effluent during the ion exchange treatment drops to 50-100, and then the ion exchange treatment is terminated. The effluent obtained by the ion exchange treatment is an organic amine solution.

2. A method for recovering organic amines from catalyst production wastewater according to claim 1, characterized in that: The temperature of the distillation treatment in step S1 is 80° C. to 100° C., and the distillation time is 2 h to 4 h.

3. The method for recovering organic amines from catalyst production wastewater according to claim 1, characterized in that: The target pH value of the pH adjustment in step S2 is 1-4.

4. The method for recovering organic amines from catalyst production wastewater according to claim 1, characterized in that: In step S2, H2O2 solution is used to adjust the pH value, and the concentration of the H2O2 solution used is 5-20 mg / L.

5. The method for recovering organic amines from catalyst production wastewater according to claim 1, characterized in that: The solid-liquid separation in step S3 adopts plate and frame filter press method.

6. The method for recovering organic amines from catalyst production wastewater according to claim 1, characterized in that: The pretreatment of the resin in the ion resin column described in step S4 includes: soaking the resin in a 32% hydrochloric acid solution for 1 hour, taking it out, and rinsing it with deionized water until the pH value of the rinsed distillate is 6-8; then soaking it in a 32% sodium hydroxide solution for 0.5 hour, rinsing it with deionized water until the pH value of the rinsed distillate is 6-8, and then soaking it in a 32% hydrochloric acid solution for 1 hour to 12 hours.

7. The method for recovering organic amines from catalyst production wastewater according to claim 1, characterized in that: The mass ratio of the resin to the mixed solution in step S4 is 1:1.5-3.

8. The method for recovering organic amines from catalyst production wastewater according to claim 1, characterized in that: In the ion exchange treatment in step S4, the speed at which the mixed solution passes through the ion resin column is 2 to 10 g / min.

9. The method for recovering organic amines from catalyst production wastewater according to claim 1, characterized in that: In the process of using the ion resin column to perform ion exchange treatment on the mixed solution in step S5, if the ion resin column penetrates, the ion resin column is eluted with an eluent, and the eluent is a hydrochloric acid solution.

10. The method for recovering organic amines from catalyst production wastewater according to claim 9, characterized in that: The concentration of the hydrochloric acid solution is 2 mol / L.

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