A kind of treatment method of thioglycolic acid production wastewater

Abstract

The invention belongs to the technical field of organic wastewater treatment, and specifically relates to a treatment method of mercaptoacetic acid production wastewater. The treatment method comprises the following steps: mixing a catalytic oxidation assistant in the mercaptoacetic acid production wastewater in advance, preheating and entering a bubbling reactor, carrying out oxidation reaction with an oxidant, thus oxidizing organic matters in the mercaptoacetic acid production wastewater into H2O, CO2 and SO4<2->; carrying out flashing and evaporation concentration on a reaction solution after reaction, and desalting. According to the treatment method disclosed by the invention, soluble manganese salt can be combined with a porous solid catalyst Nd2O5 / SiO2, and a synergistic effect between the soluble manganese salt and the porous solid catalyst Nd2O5 / SiO2 is fully exerted, so that the organic matters in the mercaptoacetic acid production wastewater can be quickly and deeply oxidized and removed; the content of COD (Chemical Oxygen Demand) in the mercaptoacetic acid production wastewater can be greatly reduced, the water and solid salt can be effectively separated, the content of the organic matters in the water and the solid salt is low, separated water can be recycled, and the solid salt can also be used as a byproduct.

Description

technical field

[0001] The invention belongs to the technical field of organic wastewater treatment, and in particular relates to a treatment method for thioglycolic acid production wastewater. Background technique

[0002] Thioglycolic acid contains both mercapto and carboxyl groups, which makes thioglycolic acid more active and has a wide range of uses. Industrial mercaptoacetic acid is mainly produced by reacting sulfur-containing nucleophiles with chloroacetate. According to different nucleophiles, it can be divided into thiourea method, sodium hydrogensulfide method, sodium thiosulfate method, sodium polysulfide method, Sodium trithiocarbonate method, alkyl sulfonate method, etc. At present, the sodium hydrosulfide method is commonly used. The salt contained in the wastewater produced by the sodium hydrosulfide method is mainly sodium chloride, and the content is relatively high, generally about 20wt.%. It also contains organic substances such as thioglycolic acid and ...

Examples

Embodiment 1

[0035] (1) Take mercaptoacetic acid production wastewater (NaCl content 17.0wt.%, COD: 20000mg / L, pH value is 0.5) and join in the wastewater storage tank, add catalytic oxidation auxiliary agent anhydrous manganese chloride and stir evenly, in the organic wastewater mn 2+ The molar concentration is 0.5mmol / L;

[0036] (2) Preheat to 200°C, enter the porous solid catalyst Nd 2 o 5 / SiO 2 React with oxygen in the bubbling reactor; control the reaction temperature to 200°C, the reaction pressure to 12.0MPa, the residence time to 60min, and the flow rate of waste water to 16.7ml / min;

[0037] (3) Sampling and analysis at the outlet of the bubbling reactor, then enter the flashing device, cool down, and centrifuge the solid salt NaCl through the desalting filter, return the concentrated solution after centrifugation to the filtering device, then enter the preheating device, and apply it to In the process, the recycling of catalytic oxidation aids is realized.

[0038] After t...

Embodiment 2

[0040] (1) Take thioglycolic acid production wastewater (NaCl content 17.0wt.%, COD: 15000mg / L, pH value is 5.0) and join in the wastewater storage tank, add catalytic oxidation auxiliary agent anhydrous manganese chloride and stir evenly, in the organic wastewater mn 2+ The molar concentration is 0.5mmol / L;

[0041] (2) Preheat to 250°C, enter the porous solid catalyst Nd 2 o 5 / SiO 2 React with oxygen in the bubbling reactor; control the reaction temperature to 250°C, the reaction pressure to 15.0MPa, the residence time to 10min, and the flow rate of waste water to 100ml / min;

[0042] (3) Sampling and analysis at the outlet of the bubbling reactor, then enter the flashing device, cool down, and centrifuge the solid salt NaCl through the desalting filter, return the concentrated solution after centrifugation to the filtering device, then enter the preheating device, and apply it to In the process, the recycling of catalytic oxidation aids is realized.

[0043] After test...

Embodiment 3

[0045] (1) Take thioglycolic acid production wastewater (NaCl content 22.0wt.%, COD: 20000mg / L, pH value is 3.0) and join in the wastewater storage tank, add catalytic oxidation auxiliary agent anhydrous manganese chloride and stir evenly, in the organic wastewater mn 2+ The molar concentration is 0.5mmol / L;

[0046] (2) Preheat to 300°C, enter the porous solid catalyst Nd 2 o 5 / SiO 2 React with oxygen in the bubbling reactor; control the reaction temperature to 300°C, the reaction pressure to 20.0MPa, the residence time to 5min, and the flow rate of waste water to 200ml / min;

[0047] (3) Sampling and analysis at the outlet of the bubbling reactor, then enter the flashing device, cool down, and centrifuge the solid salt NaCl through the desalting filter, return the concentrated solution after centrifugation to the filtering device, then enter the preheating device, and apply it to In the process, the recycling of catalytic oxidation aids is realized.

[0048] After testi...

technical field

[0001] The invention belongs to the technical field of organic wastewater treatment, and in particular relates to a treatment method for thioglycolic acid production wastewater. Background technique

[0002] Thioglycolic acid contains both mercapto and carboxyl groups, which makes thioglycolic acid more active and has a wide range of uses. Industrial mercaptoacetic acid is mainly produced by reacting sulfur-containing nucleophiles with chloroacetate. According to different nucleophiles, it can be divided into thiourea method, sodium hydrogensulfide method, sodium thiosulfate method, sodium polysulfide method, Sodium trithiocarbonate method, alkyl sulfonate method, etc. At present, the sodium hydrosulfide method is commonly used. The salt contained in the wastewater produced by the sodium hydrosulfide method is mainly sodium chloride, and the content is relatively high, generally about 20wt.%. It also contains organic substances such as thioglycolic acid and ...

Examples

Embodiment 1

[0035] (1) Take mercaptoacetic acid production wastewater (NaCl content 17.0wt.%, COD: 20000mg / L, pH value is 0.5) and join in the wastewater storage tank, add catalytic oxidation auxiliary agent anhydrous manganese chloride and stir evenly, in the organic wastewater mn 2+ The molar concentration is 0.5mmol / L;

[0036] (2) Preheat to 200°C, enter the porous solid catalyst Nd 2 o 5 / SiO 2 React with oxygen in the bubbling reactor; control the reaction temperature to 200°C, the reaction pressure to 12.0MPa, the residence time to 60min, and the flow rate of waste water to 16.7ml / min;

[0037] (3) Sampling and analysis at the outlet of the bubbling reactor, then enter the flashing device, cool down, and centrifuge the solid salt NaCl through the desalting filter, return the concentrated solution after centrifugation to the filtering device, then enter the preheating device, and apply it to In the process, the recycling of catalytic oxidation aids is realized.

[0038] After t...

Embodiment 2

[0040] (1) Take thioglycolic acid production wastewater (NaCl content 17.0wt.%, COD: 15000mg / L, pH value is 5.0) and join in the wastewater storage tank, add catalytic oxidation auxiliary agent anhydrous manganese chloride and stir evenly, in the organic wastewater mn 2+ The molar concentration is 0.5mmol / L;

[0041] (2) Preheat to 250°C, enter the porous solid catalyst Nd 2 o 5 / SiO 2 React with oxygen in the bubbling reactor; control the reaction temperature to 250°C, the reaction pressure to 15.0MPa, the residence time to 10min, and the flow rate of waste water to 100ml / min;

[0042] (3) Sampling and analysis at the outlet of the bubbling reactor, then enter the flashing device, cool down, and centrifuge the solid salt NaCl through the desalting filter, return the concentrated solution after centrifugation to the filtering device, then enter the preheating device, and apply it to In the process, the recycling of catalytic oxidation aids is realized.

[0043] After test...

Embodiment 3

[0045] (1) Take thioglycolic acid production wastewater (NaCl content 22.0wt.%, COD: 20000mg / L, pH value is 3.0) and join in the wastewater storage tank, add catalytic oxidation auxiliary agent anhydrous manganese chloride and stir evenly, in the organic wastewater mn 2+ The molar concentration is 0.5mmol / L;

[0046] (2) Preheat to 300°C, enter the porous solid catalyst Nd 2 o 5 / SiO 2 React with oxygen in the bubbling reactor; control the reaction temperature to 300°C, the reaction pressure to 20.0MPa, the residence time to 5min, and the flow rate of waste water to 200ml / min;

[0047] (3) Sampling and analysis at the outlet of the bubbling reactor, then enter the flashing device, cool down, and centrifuge the solid salt NaCl through the desalting filter, return the concentrated solution after centrifugation to the filtering device, then enter the preheating device, and apply it to In the process, the recycling of catalytic oxidation aids is realized.

[0048] After testi...

Images