(449bh) Activated Carbon Nano-Adsorbents, a Great Opportunity to Enhance the PDMS Pervaporation Membrane Performance

Biobutanol produced from Acetone-Butanol-Ethanol (ABE) fermentation is considered to be a reasonable replacement for fossil fuels. However, the need for inexpensive feed-stocks, the reduction of product inhibition via in-situ recovery to achieve higher final butanol concentration, higher yield, efficient method for solvent recovery and water recycle are the obstacles which prevented making this bio-alcohol economically viable.

Pervaporation, a membrane based-process, has a great potential for in-situ butanol recovery among different solvent recovery methods such as adsorption, liquid-liquid extraction, gas stripping, etc. Based on the studies which have been done on the pervaporation separation of the butanol, polydimethylsiloxane (PDMS) have been selected to be a reliable membrane as a result of its high hydrophobicity, ease of preparation, and their good thermal, chemical and mechanical properties. Moreover, Activated carbon adsorbent showed to have outstanding characteristics in the adsorption separation of the butanol from the ABE model solution and the binary solution of butanol. This work is the first attempt to embed the nano activated carbon particles in the matrix of the PDMS membrane to improve the performance of the butanol separation by pervaporation by increasing the flux and the selectivity of the membrane.

According to the results, permeate flux for a PDMS nano composite membrane of 6 wt% increased by 42.6% at 37°C compared to the neat membrane. Furthermore, 52% increase in the separation factor was achieved at the same concentration of the nano adsorbent.