A kind of preparation method of anti-carbon adsorption sacrificial agent of air-entraining agent

Abstract

The preparation method of the air-entraining agent anti-carbon adsorption sacrificial agent of the present invention comprises the steps: (1) adding 10 parts of lignin and 80-100 parts of solvent into the reactor to fully dissolve, and adding 3-5 parts Catalyst, then put the reactor into a microwave digestion apparatus, set the temperature at 120-150°C, and the reaction time is 15-30min, cool and filter, and obtain the filtrate for use; (2) Slowly add 40-80 parts of Carboxylation reagent, add NaOH to adjust the pH to 7~8, keep the temperature at 80~100°C, stir at 40~60r / min, and react for 2~3h; (3) Slowly add 40~60 parts of alcoholamine dropwise, control the temperature at 90 ~100℃, stirring rate 60~80r / min, reaction time 2~3h; (4) add 10~15 parts of NaOH, keep warm at 60~80℃, stirring rate 60~80r / min, react for 1~2h, and the obtained product Adjust to a solid content of 35±2% to obtain an anti-carbon adsorption sacrificial agent.

Description

Technical field [0001] The present invention relates to a technical field of concrete admixture applications, specifically to an aeration agent anti-carbon adsorption sacrificial preparation method. Background [0002] Fly ash is a powder collected in the flue gas of the coal stove of the power plant, which can be used as a concrete mineral admixture to reduce the amount of cement, reduce hydration and exothermic heat, and has "morphological effect", "activity effect" and "micro-aggregate effect", which can improve the working and durability of concrete. However, fly ash often contains unburned carbonaceous substances, which will have a large adsorption effect on the aerator and affect its gas inlet effect. [0003] A large number of tests have shown that the air bubbles introduced in the fly ash-doped induced concrete will burst over time, and the larger the amount of fly ash, the smaller the initial gas content and the greater the gas content loss. The surface of the unburned c...

AI Technical Summary

Problems solved by technology

In the large-volume fly ash concrete system, especially roller compacted concrete, the fly ash content is as high as 70%. When using air-entraining agents, there are problems such as large content, difficult air-entrainment, and unstable bubbles, which affect the resistance of concrete. Freezing poses a major hazard

[0004] The loss on ignition can reflect the carbon content in fly ash to a certain extent, but at high temperature, CaCO 3 The decomposition of carbon and the completeness of the oxidation reaction of carbon will have an impact on the loss on ignition, and cannot accurately reflect the adsorption capacity of fly ash

In addition, studies have shown that the surface of carbon particles is non-polar and hydrophobic, but there are also polar functional groups on the surface of carbon. Adsorption of aerosol molecules

[0005] According to the above analysis, in order to solve the adsorption problem of carbonaceous substances in fly ash, there are the following methods: (1) Design and prepare a new type of air-entraining agent that resists carbon adsorption, but the specific surface area of ​​carbon particles is large and contains a large number of micropores, It has a high adsorption effect on most surfactants; (2) increasing the amount of air-entraining agent leads to an increase in cost, and the effect is often not ideal; (3) using a sacrificial agent

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