一种含氟聚合物乳液的分离过程

Separation process of fluoropolymer emulsion

含氟聚合物乳液属于低浓度、高分散的非均相体系,为提高其分离效果,采用间歇式泡沫分离法研究含氟聚合物乳液的分离工艺。探索了搅拌器类型对分离效果的影响,试验结果表明:剪切作用对颗粒聚团的形成起主要作用,在同样的搅拌速度下,选用涡轮式搅拌器可以明显提高收率和富集比;比较了不同的通气方式对分离效果的影响,发现通入压缩空气可以显著提高收率和富集比。在上述条件下,运用均匀设计的方法研究通气量、温度、搅拌速度、搅拌时间、物料质量分数和氯化钙用量对分离效果的影响,利用DPS(数据处理系统)软件进行数据处理,确定乳液分离的最佳工艺条件为:通气量0.42 L/min,温度90℃,搅拌速度1 600 r/min,搅拌时间1.0 min,物料质量分数0.08,氯化钙用量0.000 2 g/mL,在此优化条件下进行验证试验,结果表明收率可达99%以上。

For improving the separation effect of the fluoropolymer emulsion which belongs to the low concentration and high dispersion of heterogeneous system,the intermittent foam separation method was adopted to study the fluoropolymer emulsion separation process.The exploration was carried out in the influences of agitator type on the separation effect.The results indicate that shear force dominates particle agglomeration,and the yield and the enrichment rate can be increased by using turbine type stirrer under the same stirring speed.The influence of different ventilation modes on the separation effect was compared,and the results show that ventilating compressed air can significantly increase the yield and the enrichment rate.Under the above conditions,the effects of ventilation,temperature,stirring speed,stirring time,material mass fraction and dosage of calcium chloride on the yield were studied by the uniform design method.The test results were processed by the DPS （Data Processing System）software and the optimal technological conditions were determined：ventilation 0.42 L/min,temperature 90℃,stirring speed 1 600 r/min,stirring time 1 .0 min,material mass fraction 0.08,dosage of calcium chloride 0.000 2 g/mL.The verification experiment was made under the optimal condition,and the results indicate that the yield is up to 99%.