Separation of 1-butanol/2,3-butanediol using ZSM-5 zeolite-filled polydimethylsiloxane membranes

Abstract

Mixed matrix membranes were prepared by incorporating ZSM-5 zeolite particles into polydimethylsiloxane. A uniform dispersion of the zeolite in the membrane was obtained. The membranes were characterized with scanning electron microscopy, and the effects of zeolite loading on membrane performance were evaluated. It was found that 80 wt.% ZSM-5 loading was optimal for selectivity. Further increase in the zeolite loading either improved the selectivity slightly or even lowered the membrane selectivity while the membrane permeability was consistently reduced. The improved separating performance of the filled membranes was attributed to the filler-polymer interactions, and the mass transfer contribution of surface flow through the zeolite pores. The advantage of the improved membrane performance was demonstrated in a simulated continuous operation enriching 2,3-butanediol in a mixture with 1-butanol from 5 to 99.5 wt.% as a retentate using both the filled and un-filled PDMS membranes. Results showed that the filled PDMS membrane improved the recovery of 2,3-butanediol significantly while achieving the same product purity.Crown

Hydrophobic nano-silica/polydimethylsiloxane membrane for dimethylcarbonate–methanol separation via pervaporation

“…8. It can be seen that incorporation of DNS-2 nano-silica particles can greatly reinforce membrane mechanical properties, which have been confirmed in many articles [25]. The tensile strength and breaking elongation ratio markedly increase with increasing DNS-2 content.…”

Process energy efficiency in pervaporative and vacuum membrane distillation separation of 2,3‐butanediol

“…Fermentation is generally a product‐inhibiting process; the economical concentrations of 2,3‐butanediol in the fermentation broth are in the range of 4–6% w/w (Shao and Kumar, 2009b). A mean value of 5% w/w was considered as the initial concentration of 2,3‐butanediol in the broth when MD was employed to enrich 2,3‐butanediol directly from the fermentation broth.…”

“…In the integrated process, 2,3‐butanediol in the fermentation broth was first extracted using 1‐butanol, and the extracted 2,3‐butanediol was further enriched by a PV membrane process. We recently investigated the PV separation of 1‐butanol/2,3‐butanediol using polydimethylsiloxane (PDMS) and PDMS filled with ZSM‐5 zeolite membranes, the results showed that the ZSM‐5‐filled PDMS membrane appears very promising for the separation (Shao and Kumar, 2009a,b, 2010). As a continued effort, this current work is dedicated to the energy aspects of the PV process, with the emphasis given to demonstrating that for conducting recovery of 2,3‐butanediol the proposed PV (the integrated process) is better than the energy‐intensive distillation.…”

Recent membrane development for pervaporation processes

“…Compared to dehydration or recovery of organic compounds from aqueous solutions, studies on MMMs for organic-organic separations are very limited. Table 9 tabulates some of their performance [184][185][186][187][188][189][190]. Most of them focused on separating the mixtures of alcohols with other organic compounds, or the mixtures of isomers and aromatic compounds.…”