Study On Synthesis Process Of Low-cost Naphthalene Superplasticizer

At present,naphthalene superplasticizer is still most widely used in China because of its superior performance,mature production technology and low production cost.In recent years,with the rising price of crude naphthalene,the cost of naphthalene superplasticizer has also been greatly increased.2,6-Naphthalenedisulfonic acid and the waste water of G acid are industrial wast which will cause unimaginable damage to the environment if direct discharge into the environment.The two kinds of substances contained in the synthesis of water reducing agent composition.According to this,two types of naphthalene superplasticizer were synthesized,using the2,6-Naphthalenedisulfonic acid and the waste water of G acid as main material.The single-factor and orthogonal experiment were used to improve synthesis process.The performance of naphthalene superplasticizer was tested by cement paste and concrete.From the tests,the following conclusions are drew: On the basis of optimization of the technological parameters,30% of G acid wastewater can be used in the synthesis of naphthalene superplasticizer.The maximum amount of 2,6-Naphthalenedisulfonic acid was 20%.The performance of the two kinds of water reducing agent is equal to the naphthalene water reducer synthesized with all crude naphthalene,but the production cost has decreased.In addition,the process of producing high concentration naphthalene water reducing agent by using 1,2-Dichloroethane as entrainer was also studied.The results show that the sulfonation time of the naphthalene superplasticizer synthesized by azeotropic method was equivalent to those synthesized by traditional technology which uses lime to neutralize excess sulfuric acid,but the sulfonation temperature should be reduced,the sulfuric acid content of former can be reduced by 25%.Compared with the naphthalene superplasticizer synthesized by traditional technology,the initial fluidity of cement paste increased under the same dosage,water-reducing ratio and concrete strength and other performance indicators have also improved.In summary,the study on the synthesis and performance of the low cost naphthalene superplasticizer,can make rational use of resources,reduce environmental pollution,cut down production costs.