阅读说明：本技术 一种胺类环氧固化剂生产废水的回收利用制备曼尼希碱固化剂的方法 (Method for preparing Mannich base curing agent by recycling amine epoxy curing agent production wastewater ) 是由 李守海 陈瑶 夏建陵 诸进华 杨小华 张燕 于 2020-06-17 设计创作，主要内容包括：一种胺类环氧固化剂生产废水的回收利用制备曼尼希碱固化剂的方法,将生产废水浓缩液、多元胺与酚、醛进行Mannich缩合反应可得到一种曼尼希碱固化剂。本发明解决了环氧固化剂生产废水处理难的问题,而且充分利用了生产废水中有效成分有机胺等作为原料制备固化剂,变废为宝,实现了生产废水充分回收利用的经济价值与现实意义。(A method for preparing a Mannich base curing agent by recycling amine epoxy curing agent production wastewater is characterized in that a Mannich base curing agent can be obtained by carrying out Mannich condensation reaction on production wastewater concentrated solution, polyamine, phenol and aldehyde. The invention solves the problem of difficult treatment of the production wastewater of the epoxy curing agent, fully utilizes the effective components of organic amine and the like in the production wastewater as raw materials to prepare the curing agent, changes waste into valuable, and realizes the economic value and practical significance of fully recycling the production wastewater.)

1. a method for preparing a Mannich base curing agent by recycling wastewater generated in amine epoxy curing agent production is characterized by comprising the following steps: (1) and (3) evaporation and concentration of epoxy curing agent production wastewater: carrying out evaporation treatment on the production wastewater, carrying out large amount of low-boiling-point organic matters out when the evaporation temperature is lower than 104 ℃, and separately collecting distillate at the low-temperature stage; collecting and biochemically treating the distillate mixture with the evaporation temperature of 104-150 ℃; recycling the concentrated solution evaporated in the kettle for later use;

(2) uniformly mixing 20-50 g of epoxy curing agent wastewater evaporation concentrate, 35-50 g of polyamine and 45-150 g of phenol, heating to 70-80 ℃, dropwise adding 15-42 g of aldehyde into the reaction liquid, controlling the dropwise adding speed, controlling the reaction temperature, keeping the reaction temperature at 80-90 ℃ after dropwise adding, keeping the temperature for 3 hours, heating for vacuum dehydration, controlling the reaction temperature at 90-120 ℃, and removing water by vacuum pressure reduction to obtain the Mannich base epoxy curing agent.

2. The method for preparing the Mannich base curing agent by recycling wastewater from the production of the amine epoxy curing agent according to claim 1, wherein the polyamine is ethylenediamine, ethanolamine, hexamethylenediamine, diethylenetriamine or triethylenetetramine.

3. The method for preparing the Mannich base curing agent by recycling wastewater from the production of the amine epoxy curing agent according to claim 1, wherein the phenol is phenol, nonylphenol or cardanol.

4. The method for preparing the Mannich base curing agent according to claim 1, wherein the aldehyde is at least one of formaldehyde, isobutyraldehyde and paraformaldehyde.

Technical Field

The invention belongs to the field of amine epoxy hardener wastewater treatment, and particularly relates to a method for preparing a Mannich base hardener by recycling amine epoxy hardener production wastewater.

Background

The amine epoxy curing agent is a substance for promoting a curing reaction, and reacts with epoxy resin to form a reticular three-dimensional polymer, and the composite aggregate is wrapped in a reticular body, so that the composite aggregate has excellent bonding, corrosion resistance, formability and thermal stability, and has excellent performances in the aspects of mechanical property, thermal property, electrical property and chemical resistance. The coating can be widely applied in national production and life, and can be used as coating, adhesive (including sealant), electric insulating material, composite material base material and the like.

In the synthesis production of the amine epoxy curing agent, the generated by-product is wastewater. The waste water contains organic amine, phenols, aldehydes and other micromolecular byproducts, has complex components, the highest COD content can reach 100000 mg/L, the emission of the waste water can seriously exceed the standard, and the waste water causes great pollution to the environment. Therefore, the amine epoxy hardener must be treated to reach the standard and discharged, but the wastewater is directly used as wastewater treatment due to too high ammonia nitrogen and COD content, so that the process is difficult to degrade, and the cost is very high, therefore, the method for preparing the hardener by recycling the wastewater generated in the production of the amine epoxy hardener has practical significance and economic value.

Disclosure of Invention

The technical problem to be solved is as follows: aiming at the technical problems, the invention provides a technical scheme of a method for preparing a Mannich base curing agent by recycling wastewater generated in the production of amine epoxy curing agents.

The technical scheme is as follows: a method for preparing a Mannich base curing agent by recycling wastewater generated in amine epoxy curing agent production comprises the following steps: (1) and (3) evaporation and concentration of epoxy curing agent production wastewater: carrying out evaporation treatment on the production wastewater, carrying out large amount of low-boiling-point organic matters out when the evaporation temperature is lower than 104 ℃, and separately collecting distillate at the low-temperature stage; collecting and biochemically treating the distillate mixture with the evaporation temperature of 104-150 ℃; recycling the concentrated solution evaporated in the kettle for later use;

(2) uniformly mixing 20-50 g of epoxy curing agent wastewater evaporation concentrate, 35-50 g of polyamine and 45-150 g of phenol, heating to 70-80 ℃, dropwise adding 15-42 g of aldehyde into the reaction liquid, controlling the dropwise adding speed, controlling the reaction temperature, keeping the reaction temperature at 80-90 ℃ after dropwise adding, keeping the temperature for 3 hours, heating for vacuum dehydration, controlling the reaction temperature at 90-120 ℃, and removing water by vacuum pressure reduction to obtain the Mannich base epoxy curing agent.

The polyamine is selected from one of ethylenediamine, ethanolamine, hexamethylenediamine, diethylenetriamine and triethylenetetramine.

The above phenol is selected from any one of phenol, nonyl phenol, and cardanol.

The aldehyde is at least one selected from formaldehyde, isobutyraldehyde and paraformaldehyde.

The preparation method is a method for preparing the curing agent by recycling the wastewater generated in the production of the amine epoxy curing agent.

Has the advantages that: (1) according to the method for preparing the Mannich base curing agent by recycling the production wastewater of the amine epoxy curing agent, the effective components of organic amine and the like in the production wastewater are fully utilized as raw materials to prepare the curing agent with excellent performance, so that the ammonia nitrogen and COD content in the wastewater is greatly reduced, the emission standard is met, the problem of wastewater treatment is solved, a large amount of valuable organic matters, especially the organic amine, in the wastewater is recycled, and the waste is changed into valuable. (2) The invention can recover the organic matters in different production wastewater by adopting different treatment processes, has wide application range and strong practicability. (3) The invention has simple treatment process and high value of recovered products, and greatly reduces the treatment cost of wastewater.

Detailed Description

Some examples are given below to further illustrate the present invention, but the following examples are not intended to limit the scope of the present invention, and those skilled in the art should make some insubstantial modifications and adaptations to the present invention.