REMOVING THIOPHEN FROM COKING BENZENE AND MAKING PURE THIOPHEN FROM THE THIOPHEN FRACTION BY EXTRACTIVE RECTIFICATION. INDUSTRIAL PLANT DESIGN

摘要

In the 1960s and 1970s, the technological laboratory at this institute devised a method of making pure thiophen by extractive rectification of the commercial thiophen fraction (30-35 percent) made at the Makeev coking and chemical plant by periodic rectification with a high-performance column with large phlegm numbers (R = 30-50). The process involved considerable energy consumption, which made it not very competitive. As separating agents, proposals have been made for organic solvents such as A^AZ-dimethylformamide (DMFA), V-methylpyrrolidone, and certain others [1]. These compounds increase the relative volatility in the benzene-thiophen system from a =1.13 to a = 1.45-1.60, so rectification columns of ordinary performance could be used with low phlegm numbers. The products are purified benzene and pure thiophen. The method was checked out with an enlarged test system (patch column of diameter 70 mm) in continuous operation by the use of DMFA as separating agent.