Circular production of hexamethylolmelamine

A hexamethylol melamine and production process technology, applied in the field of hexamethylol melamine, can solve the problems of easy clogging of filter cloth, inability to effectively recycle or process, inconvenient cleaning, etc., and achieve the effect of reducing production costs

Active Publication Date: 2019-03-08
李平
View PDF3 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The problems existing in these technologies are that there are many aldehyde-containing waste water and great pollution, and the mother liquor after separation and dehydration is in the form of paste, which is not conducive to the recycling of the mother liquor
In addition, the filter cloth is easily blocked during centrifugation, which is not easy to clean, and a large amount of formaldehyde-containing washing wastewater is generated during cleaning, which cannot be effectively recycled or treated.

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
  • Circular production of hexamethylolmelamine
  • Circular production of hexamethylolmelamine

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0038] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0039] Such as figure 1 As shown, the production process of hexamethylolmelamine of the present invention generally includes adding formaldehyde, melamine, and alkali in a hydroxylation reactor to react, centrifuging and drying to obtain the product and packaging it. The exhaust gas generated during the centrifugation and drying process is passed to the exhaust gas treatment tower for subsequent treatment. The mother liquor separated by centrifugation is recycled as raw material for production in the whole process. The specific circulation production process is as follows:

[0040] 1) Add water or (recycle) mother liquor in the hydroxylation reactor;

[0041] 2) adding formaldehyde aqueous solution to the reaction kettle, and keeping the formaldehyde content at 10% to 25%, preferably 15% to 20%;

[0042] 3) Stir and heat the solution in the kettle to 40-80°C, pref...

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

Disclosed is a process of cyclically producing hexamethylolmelamine, comprising: adding a mother liquid and high-concentration formaldehyde aqueous solution in a hydroxylation reaction kettle; stirring and heating the solution in the kettle; adding alkali in the reaction kettle, and pre-adjusting a pH value of the solution in the kettle; then adding melamine in the reaction kettle; adding alkali again into the reaction kettle, and adjusting the pH value of the solution in the kettle; raising a temperature of the reaction solution in the kettle for reaction; introducing the solution in the kettle which has already been cooled into a centrifuge for centrifugal separation to obtain hexamethylolmelamine wet material and the mother liquid; delivering the hexamethylolmelamine wet material to a drying system for subsequent drying; returning the mother liquid back to the reaction kettle; and repeating the above steps for cyclic production. By using high-concentration formaldehyde, the present disclosure enables the mother liquid to be cyclically used for a production procedure, thereby substantially reducing the product costs and achieving zero-pollution emission.

Description

technical field [0001] The invention relates to a new environment-friendly production process of hexamethylolmelamine. Background technique [0002] Hexamethylolmelamine is used in the rubber adhesive industry to react with alcohols to produce rubber adhesive A, which is widely used in strengthening the bonding of rubber and cords. Etherified products can also be used in coil coatings and automotive coating additives. [0003] At present, the production of hexamethylol melamine generally adopts melamine and 37% formaldehyde aqueous solution or paraformaldehyde as raw materials to carry out methylolation reaction under alkaline conditions, and the product is obtained after dehydration and drying. The problems that all exist in these technologies are that there are many aldehyde-containing wastewaters and great pollution, and the mother liquor after separation and dehydration is in a paste state, which is not conducive to the recycling of the mother liquor. In addition, the ...

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 Patents(China)
IPC IPC(8): C07D251/64
CPCC07D251/64C08G12/32
Inventor 李平王文武唐学军唐琼
Owner 李平
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products