Activated Carbon-Loaded Polydimethylsiloxane Membranes for the Pervaporation of 1-Butanol from Aqueous Solutions

Abstract

Butanol has shown potential as an alternative biofuel. It can be obtained through ABE fermentation, which produces 1-butanol, ethanol and acetone. Pervaporation is a potential separation process, since it can be successfully applied to remove trace components such as butanol, which is toxic to the cells. The development of an effective membrane is the limiting factor for this technology. Activated carbon-containing polydimethylsiloxane membranes were prepared by varying the filler content up to 2 wt%. The resulting membranes were characterized for the separation of model solutions with 1-butanol, acetone, ethanol and water by pervaporation. The effects of activated carbon load (0, 1, 2 wt%) and temperature (25, 40, 55ºC) on flux and separation factor were evaluated. The addition of 1 wt% activated carbon increased membrane free volume, changed surface morphology and showed flux of 45 g/m 2 h, with separation factor for 1-butanol of 370, at 55ºC.

Adsorption of Acetone, Butanol, and Ethanol in Activated Carbon Aiming the Separation of Organics From Diluted Aqueous Solutions

“…The flasks were placed in water bath at 27 °C, pressure of 1 atm, and stirred at 150 rpm for 8 hours. Samples of 1 mL were collected for the times of 0, 60, 71, 120, 180, 240, and 420 min, and analyzed by a gas chromatograph model GC-17A (Shimadzu Europe) of the Flame Ionization Detector (FID) type according to the methodology proposed in a previous work (Gonçalves et al, 2019). The decrease in butanol concentration in the solution with time was evaluated.…”

“…Kinetic and equilibrium data were compared to evaluate time and reversibility of such adsorbents aiming the selection for different applications. Besides the adsorption behavior, the selection of activated carbon to be used as a filler in mixed matrix membranes for ABE separation from fermentation broth was evaluated, as in a previous work (Gonçalves et al, 2019).…”

Developments in Downstream Butanol Separation from Acetone, Butanol, and Ethanol Fermentation

“…Gonçalves et al. 66 investigated the use of carbon‐activated loaded PDMS membrane for the removal of ABE from aqueous solutions. The result for 1 wt% of filler, at 55 °C, revealed a flux of 45 g m −2 h −1 and separation factor of 370.…”

Mixed matrix membranes of polydimethylsiloxane with activated carbon for ABE separation

“…[5][6][7][8] One of the major routes to accomplish ABE separation is pervaporation. [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] As a membrane separation process, pervaporation is suitable to be coupled with fermentation since it does not require high temperature or harsh conditions. It is based on the permeation and evaporation of a chemical, due to its affinity with membrane material and phase change across the membrane due to the low pressure in permeate side.…”

“…[14][15][16][17][18]24 More recently, literature has shown the investigation of activated carbon (AC) as PDMS filler for ABE separation due to the low cost of the filler. 25,26 Azimi and coworkers investigated mixed matrix membranes based on the dispersion of 6 wt% of AC in PDMS for the separation of butanol from water (0.5 wt%) at 37 C. 25 The results of pervaporation showed a flux of 44.5 g m À2 h À1 and separation factor of 25.2 where ascribed to the increase in butanol sorption combined with nanoporous structure for butanol permeation. Gonçalves and coworkers used AC/PDMS membranes for the removal of ABE from aqueous solution (2 wt%), at 55 C, and reported a flux of 45 g m À2 h À1 and separation factor of 370, which was explained due to the energy for butanol desorption from the membrane.…”