Solvent For Separation Of C4Hydrocarbons And Optimization Of SBAC Process

C4fraction is the most widely used oil and gas resources following ethylene andpropylene. It is mainly from petroleum cracking gas and DCC. It is difficult toseparate C4fraction by simple distillation due to their close relative volatility. Nowextractive distillation is widely used to separate C4fractions in industry, and thescreening of the appropriate solvent is the key work. In this paper, we discuss thesolvent in the separation of C4fraction in recent, such as NFM/MEK, ACN, DMF.The solvent system such as NFM/MEK, ACN, NMP/MEK, NMP/MEK/H2O,.NMP/H2O were also studied by using simulation and experimental research method, andNMP/MEK/H2O showed advantages compared with other systems in the area ofseparation efficiency and energy consumption, and with less effective to theenvironment and the consequent reaction, which can applied to industrializationproduction as a new solvent.This article uses extractive distillation to concentrate butene of C4fraction aftersec-butyl acetate (SBAC) reacting, the concentration of butene can reach90-95%,The concentrated butene enters into reactor with the concentration of70-80%aftermixed with the fresh C4material，The inlet butene concentration of SBAC reactorcould be enhanced, SBAC production increased, tail gas of C4decreased, and thecoefficient of utilization of butene improved. In some cases, part of the reacted C4recycled to C4extractive distillation section and butene to concentrated, the other partof the reacted C4directly combined with the concentrated butene then be introducedinto SBAC reactor, in these cases the processing capacity of C4extractive distillationcan be reduced, investment and energy consumption reduced too. In these cases theconcentration of butene into SBAC reactor can be free adjusted, so that the reactorworked at the best condition.