AZEOTROPIC MIXTURE COMPOSED OF 1,1-DIFLUOROETHANE AND HYDROGEN FLUORIDE AND PROCESS FOR PRODUCING 1,1-DIFLUOROETHANE

摘要

The invention provides a minimum-boiling-point azeotropic binary mixture substantially composed of hydrogen fluoride (HF) and 1,1-difluoroethane (HFC-152a). Also provided is a process for producing HFC-152a comprising the steps of distilling a mixture containing HFC-152a and HF, drawing an azeotropic mixture out of the column top, and recovering either HFC-152a-free HF or HF-free HFC-152a from the column bottom, thereby recovering more effectively either HFC-152a-free HF or HF-free HFC-152a.