共水解法制备低黏度硅油返酸机理研究及工艺优化

Study on the Acidification Mechanism and Process Optimization of Low Viscosity Silicone Oil by Cohydrolysis

以合成甲基氯硅烷单体的副产物为原料,通过逆向共水解制备低黏度硅油,提出了硅油油包水(W/O)型乳液失稳析水的返酸机理,采用热盐水(稀NaCl)+弱碱液(稀Na2CO3)两级水洗工艺,取代现有固碱中和方案对油品进行精制,并利用正交实验对相关参数进行了优化。较佳的工艺条件为:NaCl浓度为2%～3%、Na2CO3浓度为10%～12%、洗涤温度为85～90℃、洗涤接触时间>10 min。采用新工艺在该条件下对油品进行处理,可解决硅油返酸问题,降低了操作人员的作业强度,改善了作业环境,提高了硅油收率。

Based on the synthesis of methylchlorosilane as the raw materials,the low viscosity silicone oil was prepared by reverse cohydrolysis.The acidification mechanism of the water-in-oil(W/O)emulsion was analyzed.The refining process,a two-stage washing process of hot brine(diluted NaCl solution)and weak alkali solution(diluted Na 2 CO 3),was used to replace the existing solid alkali-base neutralization to refine the oil,and the relevant parameters were optimized by orthogonal experiment.The preferred process conditions are as follows:the concentration of NaCl is 2%~3%,the concentration of Na 2 CO 3 is 10%~12%,the washing temperature is 85~90℃,and the washing contact time is more than 10 min.The new process treating the oil under the conditions can prevent the acidification of the silicone oil,reduces the operating strength of the operator,improves the working environment,and increases the yield of the silicone oil.