Pervaporation separation of thiophene-heptane mixtures with polydimethylsiloxane (PDMS) membrane for desulfurization.
Cross-linked polydimethylsiloxane (PDMS)-polyetherimide (PEI) composite membranes were prepared, in which asymmetric microporous PEI membrane prepared with phase inversion method was acted as the microporous supporting layer in the flat-plate composite membrane. Membrane characterization was conducted by Fourier transform infrared and scanning electronic microscopy analysis. The composite membranes were employed in pervaporation separation of n-heptane-thiophene mixtures. Effect of amount of PDMS, cross-linking temperature, amount of cross-linking agent, and cross-linking time on the separation efficiency of n-heptane-thiophene mixtures was investigated experimentally. Experiment results demonstrated that 80-100 degrees degrees C of cross-linking temperature was more preferable for practical application, as the amount of cross-linking agent was up to 20 wt.%, and 25 wt.% of PDMS amount was more optimal as far as flux and sulfur enrichment factor were concerned. In addition, the swelling degree of and stableness of composite membrane during long-time operation were studied, which should be significant for practical application.
Chen
Jian
J
Department of Chemical Engineering, Tsinghua University, Beijing, China.
Li
Jiding
J
Qi
Rongbin
R
Ye
Hong
H
Chen
Cuixian
C
D000327:Adsorption; D003432:Cross-Linking Reagents / Q000737:chemistry*; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D006536:Heptanes / Q000737:chemistry*; D008567:Membranes, Artificial; D013499:Surface Properties; D013876:Thiophenes / Q000737:chemistry*
D003432:Cross-Linking Reagents; D004129:Dimethylpolysiloxanes; D006536:Heptanes; D008567:Membranes, Artificial; D013876:Thiophenes; C028618:n-heptane; C013830:baysilon