A method of using natural chitin to prepare bio-based retarding high-efficiency water reducer

A high-efficiency water-reducing agent and chitin technology, which is applied in the field of using natural chitin to prepare a bio-based retarding high-efficiency water-reducing agent, can solve the problems of limited use, easy bleeding of concrete, physical health damage, etc., and can save material costs. Expenses, low commercial prices, and the effect of improving utilization efficiency

Active Publication Date: 2019-03-19
JINLING INST OF TECH
View PDF7 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The production process of aliphatic high-efficiency superplasticizers is simple, and the cost is lower than that of naphthalene-based high-efficiency superplasticizers. However, the color of concrete mixed with aliphatic high-efficiency water-reducers will turn yellow, which affects the promotion of aliphatic high-efficiency water-reducers in actual projects. application
The sulfamic acid high-efficiency water reducer has a good dispersion effect on cement particles, and can effectively control the slump loss, but the raw material price of the sulfamate high-efficiency water-reducer is relatively high, and the addition of the sulfamate high-efficiency water-reducer The concrete is easy to bleed, which affects its use in actual engineering
As a new type of high-efficiency water-reducing agent, polycarboxylate superplasticizer has high dispersion performance on cement particles at a small dosage, and has excellent slump-retarding effect, but the high-efficiency water-reducing agent mixed with polycarboxylate The disadvantages such as high air content in concrete and high cost of raw materials for preparing polycarboxylate superplasticizers limit the wide use of polycarboxylate superplasticizers in HPC.
At the same time, the raw materials used in the preparation process of the above types of high-efficiency water reducers are mostly toxic and harmful petrochemical products, and the preparation process will pollute the surrounding environment and cause harm to human health.

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
  • A method of using natural chitin to prepare bio-based retarding high-efficiency water reducer
  • A method of using natural chitin to prepare bio-based retarding high-efficiency water reducer
  • A method of using natural chitin to prepare bio-based retarding high-efficiency water reducer

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0040] According to the method described in this patent technology, a batch (1 ton) of natural chitin bio-based retarding superplasticizer is produced for concrete application research.

[0041] Preparation of natural chitin bio-based retarding superplasticizer

[0042] 1. Preparation of oligomeric chitin

[0043] Weigh 160-170kg of natural chitin polymer (the weight average molecular weight is 411,900) and 830-840kg of water into a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel, and a reflux condenser, and proceed at a certain speed. After stirring, the chitin polymer is dispersed into the water to form a uniform suspension solution. Raise the temperature to 60°C, add dropwise a mixed solution of 15-17kg hydrogen peroxide (50% concentration) and 5-7kg acetic acid (99.8% concentration) under stirring, control the temperature not to exceed 60°C, and complete the addition within 30 minutes , React at a temperature of 65-70°C for 3 hours to obtain a s...

Embodiment 2

[0049] According to the method described in this patent technology, a batch (1.5 tons) of natural chitin bio-based retarding superplasticizer was produced for concrete application research.

[0050] Preparation of natural chitin bio-based retarding superplasticizer

[0051] 1. Preparation of oligomeric chitin

[0052] Weigh 240-255kg of natural chitin polymer (weight-average molecular weight: 411,900) and 1200-1300kg of water into a reaction vessel equipped with a stirrer, thermometer, dropping funnel, and reflux condenser, and stir at a certain speed , chitin polymer dispersed in water to form a uniform suspension solution. Raise the temperature to 60°C, add dropwise a mixed solution of 22-25.5kg hydrogen peroxide (50% concentration) and 7.5-10.5kg acetic acid (99.8% concentration) while stirring, control the temperature not to exceed 60°C, and add in 30 minutes Complete reaction at 65-70°C for 3.5 hours to obtain a semi-clear solution of oligomeric chitin. The molecular w...

Embodiment 3

[0058] According to the method described in this patent technology, a batch (2 tons) of natural chitin bio-based retarding superplasticizer was produced for concrete application research.

[0059] Preparation of natural chitin bio-based retarding superplasticizer

[0060] 1. Preparation of oligomeric chitin

[0061] Weigh 320-340kg of natural chitin polymer (the weight average molecular weight is 411,900) and 1660-1680kg of water into a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel, and a reflux condenser, and proceed at a certain speed. After stirring, the chitin polymer is dispersed into the water to form a uniform suspension solution. Raise the temperature to 60°C, add dropwise a mixed solution of 30-34kg hydrogen peroxide (50% concentration) and 10-14kg acetic acid (99.8% concentration) under stirring, control the temperature not to exceed 60°C, and complete the addition within 30 minutes , React at a temperature of 65-70°C for 3 hours to obta...

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 relates to a method for preparing a bio-base high-efficiency delayed-coagulation water-reducing agent from natural chitin. The method comprises the following steps: degrading a natural high polymer, and carrying out functional group remolding, so as to obtain a chitosan oligosaccharide intermediate containing functional groups such as amino and hydroxymethyl; carrying out condensation reaction by virtue of phenol and formaldehyde under alkaline conditions so as to generate a phenolic aldehyde intermediate, and carrying out addition reaction by virtue of sodium hydrogen sulfite and formaldehyde so as to introduce hydrophilic sulfonic acid groups to the phenolic aldehyde intermediate; and linking the chitosan oligosaccharide intermediate with the sulfonated phenolic aldehyde intermediate by virtue of hydroxymethyl polycondensation, so as to obtain the bio-base high-efficiency delayed-coagulation water-reducing agent with good water-reducing and delayed-coagulation effects. The chitin bio-base high-efficiency delayed-coagulation water-reducing agent has the characteristics of low raw material cost, environment-friendly protection process and the like and further has relatively good water-reducing and delayed-coagulation effects. The chitin bio-base high-efficiency delayed-coagulation water-reducing agent has economic and environmental protection benefits and is a novel high-efficiency water-reducing agent with great promise.

Description

technical field [0001] The invention relates to a method for preparing a water reducer by using natural biomass materials, in particular to a method for preparing a bio-based slow-setting high-efficiency water reducer by using natural chitin. Background technique [0002] High-performance concrete (HPC) has been widely used in civil engineering structures, and the total output of HPC in the world in 2016 reached 11.3 billion m 3 . HPC has the characteristics of no segregation, easy pouring and compaction, good mechanical properties and volume stability, high toughness, and long service life under harsh service conditions. High-efficiency water reducer is an important component in the preparation of HPC. Adding high-efficiency water reducer to concrete can improve the dispersion performance of cement particles and release the free water in cement aggregates. While keeping the working performance of concrete unchanged, it can reduce the water-cement ratio of concrete, impro...

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): C08G8/28C08B37/08C04B24/16C04B103/30
CPCC04B24/168C04B2103/302C08B37/003C08G8/28
Inventor 赵晖陈达廖迎娣欧阳峰杜杨徐海生
Owner JINLING INST OF TECH
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