Meanwhile the refining process was improved, using crystallization from petroleum-benzene instead of highvacuumdistillation. The process was simplified for the benefit of industry production.
同时改进了精制工艺，用石油醚-苯进行结晶代替高真空蒸馏，简化了工艺，有利于工业化生产。
2
The refined product with high purity is obtained by vacuumdistillation of crude benzal chloride.
将制得的苄叉二氯粗品进行真空精馏得到高纯度的精品；
3
The new liquid distributor has been already applied in revamping of the washing zone in crude vacuumdistillation tower with high temperature, small flowrate, dirt and easy-coking material.