Unlock instant, AI-driven research and patent intelligence for your innovation.

Resourceful treatment method of 1, 2, 3, 6-tetrahydrophthalimide production wastewater

A technology of tetrahydrophthalimide and a treatment method, applied in the field of wastewater treatment, can solve the problems of increasing disposal costs, waste of resources, etc., and achieve the effects of offsetting disposal costs, easy operation and good economic benefits

Pending Publication Date: 2022-08-05
SHANDONG WEIFANG RAINBOW CHEM
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, the crystallization wastewater is mostly treated by distillation, that is, the wastewater is directly distilled, and the fraction is subjected to biochemical treatment. The obtained filter residue contains more than 40wt% of 1,2,3,6-tetrahydrophthalimide. At present, the filter residue is directly disposed of as hazardous waste, which causes a serious waste of resources and increases the cost of disposal
[0003] At present, there is no relevant report on how to recover this part of 1,2,3,6-tetrahydrophthalimide. Therefore, crystallization from 1,2,3,6-tetrahydrophthalimide Recovery of 1,2,3,6-tetrahydrophthalimide from mother liquor wastewater has good economic and social significance

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Resourceful treatment method of 1, 2, 3, 6-tetrahydrophthalimide production wastewater

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0037] (1) Acid adjustment and replacement: take 5000 g of wastewater, acidify the wastewater with 60 g of 10% dilute hydrochloric acid, and the pH of the wastewater after acidification is 2.3, so that 1,2,3,6-tetrahydrophthalimide is treated with hydrochloric acid. It exists in the form of salt and is easily soluble in water;

[0038] (2) Extraction: Mix the wastewater and the extractant (cyclohexane) in a volume ratio of 5:1 to extract other organic substances in the wastewater, mainly tetrahydrophthalic acid; fully stir, and then statically stratify for 15 minutes, and The oil phase and the water phase are separated, and the oil phase is adjusted to alkali to make the organic acid form sodium salt and then removed from the oil phase. After separation, the extractant can be recycled and applied. After extraction, the water phase COD=29850mg / L, and the removal rate is 27.2%. ;

[0039] (3) Alkali-adjusting replacement: the aqueous phase after extraction and stratification is...

Embodiment 2

[0043] (1) Acid adjustment and replacement: take 5000 g of wastewater, acidify the wastewater with 90 g of 7% dilute hydrochloric acid, the pH of the wastewater after acidification is 1.7, and make 1,2,3,6-tetrahydrophthalimide with hydrochloric acid. It exists in the form of salt and is easily soluble in water;

[0044] (2) Extraction: The waste water and the extractant (hexane) are mixed in a volume ratio of 10:1 to extract other organic substances in the waste water, mainly tetrahydrophthalic acid; fully stirred, and then statically stratified for 20 minutes, and the oil was removed. The phase and the water phase are separated, and the oil phase is adjusted to alkali to make the organic acid form sodium salt and then removed from the oil phase. After separation, the extractant can be recycled and applied. After extraction, the water phase COD=27991mg / L, and the removal rate is 31.7%;

[0045] (3) Alkali adjustment and replacement: The aqueous phase after extraction and stra...

Embodiment 3

[0049] (1) Acid adjustment and replacement: take 5000g of wastewater, acidify the wastewater with 136g of 5% dilute hydrochloric acid. It exists in the form of salt and is easily soluble in water;

[0050] (2) Extraction: The waste water and the extractant (cyclohexane, hexane mixture) are mixed according to the volume ratio of 15:1, and other organic substances in the waste water are extracted, mainly tetrahydrophthalic acid; Layer 30min, and separate the oil phase and the water phase, the oil phase is adjusted to alkali to make the organic acid form sodium salt and removed from the oil phase, after separation, the extractant can be recycled and applied, after extraction, the water phase COD=30551mg / L, remove The rate was 25.5%;

[0051] (3) Alkali-adjusting replacement: the aqueous phase after extraction and stratification is adjusted to alkaline with liquid caustic soda, the concentration of liquid caustic soda is 15%, the pH of wastewater is adjusted to 9.6, the dosage is...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a resourceful treatment method of 1, 2, 3, 6-tetrahydrophthalimide production wastewater, which comprises the following steps: adding acid into 1, 2, 3, 6-tetrahydrophthalimide crystallization mother liquor for acidification, mixing the acidified crystallization mother liquor with an extraction agent, extracting, separating liquid, adding water into a water phase for alkalization, enabling the alkalized water phase to pass through a resin column, and carrying out resourceful treatment on the 1, 2, 3, 6-tetrahydrophthalimide production wastewater to obtain the 1, 2, 3, 6-tetrahydrophthalimide production wastewater. 2, 3, 4, 6-tetrahydrophthalimide is added for enrichment; and eluting the resin column with an acid, adjusting the pH value of the obtained desorption solution to be alkaline, crystallizing, and filtering to obtain the 1, 2, 3, 6-tetrahydrophthalimide. The existing form of the 1, 2, 3, 6-tetrahydrophthalimide in the wastewater is changed through acid-base adjustment, purification of the wastewater and effective recovery of the 1, 2, 3, 6-tetrahydrophthalimide are achieved by combining extraction and resin adsorption technologies, the economic value of the recovered product can be used for counteracting the treatment cost of the three wastes, and the economic benefit is good.

Description

technical field [0001] The invention relates to a method for treating wastewater from chemical production, in particular to a method for treating wastewater from 1,2,3,6-tetrahydrophthalimide production as a resource, and belongs to the technical field of wastewater treatment. Background technique [0002] 1,2,3,6-Tetrahydrophthalimide (referred to as tetrahydroimide) is an important intermediate in the synthesis of pesticides, which can be used for the synthesis of captandan. The price is 20,000 to 30,000 yuan per ton. higher. The production method of 1,2,3,6-tetrahydrophthalimide is as follows: 1,2,3,6-tetrahydrophthalic anhydride and ammonia source are mixed and reacted to obtain an intermediate, and then the intermediate is carried out. Ring-closing reaction, recrystallization after cooling to obtain the product 1,2,3,6-tetrahydrophthalimide. In the process of producing 1,2,3,6-tetrahydrophthalimide, a large amount of waste water will be produced at the same time, in w...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C02F9/10C07D209/48C02F1/66C02F1/28C02F1/04C02F1/26
CPCC02F9/00C07D209/48C02F1/66C02F1/28C02F1/04C02F1/26C02F2103/36Y02W10/37
Inventor 李志清程元刚梁倩凌晓光王峰徐加霸魏继宽赵岭树王宗浩
Owner SHANDONG WEIFANG RAINBOW CHEM