Preparation of Epoxidized SBS Triblock Copolymer and Its Methane Separation from Low-Concentration Coal-Bed Methane

By : Tengyang Zhu , Xing Yang , Xiaoqi He , Ziqin Si , Jujie Luo

Page No: 421-437

Abstract
A series of gas separation membranes from epoxidized SBS (ESBS) with various conversion rates were synthesized via epoxidation reaction. The structures of this series were confirmed by fourier transform infrared spectroscopy (FT-IR) and 1 H-NMR spectroscopy. Thermal stability of the ESBSs membranes were characterized by thermogravimetric analysis (TGA). The permeability and selectivity of the membranes were studied at different temperatures of 25–55 °C and pressures of 0.5–1.5 atm, using single gases CH4 ,O2 and N2 . Pure-gas permeation measurements showed that gas permeability decreased and the selectivities of CH4 /N2 and O2 /N2 were improved with the increasing of conversion rate of double bonds. Mixed-gas permeation studies were further performed by analyzing SBS and ESBSs membranes performance using air (O2 /N2 =21/79 vol%) and low-concentration coal-bed methane gas (CH4 /N2 /O2 =8.6/74.8/16.6 vol%, named LCCBM). The result demonstrates that it has a good performance to separate mixed gas for ESBSs membranes than SBS membrane. Especially for ESBS5 membrane, the O2 and N2 volume fraction reach to 47.6 vol% and 47.9 vol% for LCCBM.

Authors :
Tengyang Zhu, Xing Yang, Xiaoqi He, Ziqin Si and Jujie Luo : College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan, 030024, PR China