Production technology of FDN superplasticizer

Abstract

The invention discloses a production technology of an FDN superplasticizer, and solves the problems that by a method for reducing the sodium sulfate content of a product through reduction in the addition amount of concentrated sulfuric acid, the amount of naphthalene participating in a sulfonation reaction is reduced, a large amount of unreacted naphthalene participates in a condensation reaction,thus sulfonated groups on unit naphthalene are reduced, and after the sulfonated groups on unit naphthalene are reduced, the product performance is easily affected. The production technology mainly comprises the following steps: melting refined naphthalene or industrial naphthalene, performing the sulfonation reaction, performing a hydrolysis reaction, performing a condensation reaction and performing a neutralization reaction. In the sulfonation process, an excessive amount of waste material containing a polynaphthalene sulfonate-based compound is added as a reaction raw material, so that the purposes of avoiding easy influence of reduction in the concentration of the sulfuric acid on the normal reaction, performing the reaction more fully and increasing the yield are achieved.

Description

technical field [0001] The invention relates to a production process of a water reducer, more specifically, it relates to a production process of an FDN high-efficiency water reducer. Background technique [0002] Due to the needs of industrial development, people have put forward higher and higher requirements for the performance of concrete, and a necessary condition for realizing the high performance of concrete is the use of high-efficiency water reducing agent, which can not only improve construction conditions, but also improve the compressive and flexural resistance of concrete Strength, but also can enhance the anti-freeze and anti-seepage properties of concrete. Most of the high-efficiency water-reducers currently used are naphthalene-based water-reducers, among which FDN high-efficiency water-reducers have strong high-dispersibility and low-foaming properties. Features: It has a strong dispersion effect on cement particles, which can greatly improve the comprehensi...

AI Technical Summary

Problems solved by technology

However, during the sulfonation reaction process of this preparation method, the concentration of sulfuric acid decreases, which is likely to affect the normal progress of the reaction. Although the preparation method of this naphthalene-based water reducer reduces the content of sodium sulfate in the product, it will reduce the amount of sodium sulfate that participates in the sulfonation reaction. The amount of naphthalene will cause a large amount of unreacted naphthalene to participate in the condensation reaction, reducing the sulfonated group on the unit naphthalene. After the reduction of the sulfonated group on the unit naphthalene, the performance of the product is easily affected

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