Recovery of polyvinyl chloride from tetra:hydro-furan - by addn. water with surfactant to prevent deposit

摘要

The parent patent refers to a method of separating PVC from soln. in THF, in which the water content is adjusted to 10-50 wt. % before distn. In this addn. 0.1-3.0%, wrt. to the water, of a surfactant is also added before distn. The original method effected practically complete recovery of THF leaving a PVC residue which was easily removable from the distn. vessel and easy to filter. Because of the complete separation of tetrahydrofuran the residue was neither noxious nor polluting. However, the method caused a deposit to form on the wall of the distn. vessel which has to be removed mechanically. The addn. of a surfactant eliminates this defect.