添加剂对含盐四氯化碳-水乳状液的稳定作用

Effect of Additive on Stability of Carbon Tetrachloride-Water Emulsion Containing Electrolyte

在恒定乳化机转速和白炭黑含量的条件下,以白炭黑作为固体粉末稳定剂制备了四氯化碳-水乳状液,用恒定含量的氯化钾作为背景电解质,采用电导法研究了不同含量的聚乙二醇-600(PEG-600)和吐温-80(Tween-80)添加剂对含盐四氯化碳-水(体积比为1∶1)乳状液的稳定作用,通过提出增比电导率和初始分层速率常数的概念对乳状液的动力学稳定性进行了分析。分析结果表明,PEG-600在低含量时对乳状液有聚沉作用,加快了油水分层速率;在中等含量时对乳状液具有一定的稳定作用;在高含量时乳状液出现转相现象,又导致乳状液不稳定。添加0.20%(质量分数)的Tween-80后,乳状液初始分层速率常数从0.098min-1急剧降至0.009min-1,未出现乳状液转相现象。

Carbon tetrachloride - water emulsion with silica aerogel as stabilizing agent was prepared under constant homogenizer rotating speed and constant silica aerogel content. Effects of polyethylene glycol （ PEG - 600） and Tween - 80 contents on stability of carbon tetrachloride - water emulsion containing constant amount of electrolyte were investigated by conductivity method. The concept of incremental ratio of conductivity in rich oil phase was proposed to describe relationship between stability and conductivity of the emulsion. Stability of the emulsion was studied through initial creaming rate constant. Low concentration PEG- 600 showed aggregation effect to the emulsion, medium concentration PEG- 600 could stabilize the emulsion to some degree, and high concentration PEG -600 resulted in phase inversion of the emulsion. After addition of 0.20% （mass fraction） Tween -80, the initial creaming rate constant of the emulsion decreased sharply from 0.098 min^-1 to 0.009 min^-1, and phase inversion did not take place. So the addition of 0.20% Tween - 80 is favorable to stability of the emulsion.