Flemish Institute for Technological Research (VITO), Business Unit Separation and Conversion Technology, Mol, Belgium.
Bioresour Technol. 2013 Feb;129:421-9. doi: 10.1016/j.biortech.2012.11.072. Epub 2012 Nov 29.
Acetone, butanol and ethanol were produced in a continuous two-stage fermentation integrated with pervaporation using freely suspended cells of C. acetobutylicum ATCC 824. PDMS composite pervaporation membranes were directly coupled to the second fermentor which lead to decreased solvent titers. Overall productivity was increased from 0.45 g L(-1) h(-1) to 0.88 g L(-1) h(-1) when increasing the carbohydrate concentration in the feed from 60 to 120 g L(-1). The highest overall productivity of 1.13 g L(-1) h(-1) was achieved when increasing the carbohydrate concentration further to 150 g L(-1) even though productivity decreased significantly in the first fermentor due to substrate inhibition. In this phase that lasted 200 h, the average flux reached 0.621 kg m(-2) h(-1) and the total solvent concentration in the permeate was 202 g L(-1). High solvent titers in the second fermentor were beneficial for the performance of the pervaporation unit leading to higher fluxes and total solvent concentrations in the permeate.
丙酮、丁醇和乙醇在利用游离悬浮的 C. acetobutylicum ATCC 824 细胞进行的连续两段发酵与渗透蒸发集成系统中生成。聚二甲基硅氧烷复合渗透蒸发膜直接与第二发酵罐相连，这导致溶剂浓度降低。当进料中的碳水化合物浓度从 60 克/升增加到 120 克/升时，整体生产力从 0.45 克/升/小时增加到 0.88 克/升/小时。当进一步将碳水化合物浓度增加到 150 克/升时，整体生产力达到了 1.13 克/升/小时，尽管由于基质抑制，第一发酵罐中的生产力显著下降。在持续 200 小时的这一阶段，平均通量达到 0.621 千克/平方米/小时，渗透物中的总溶剂浓度为 202 克/升。第二发酵罐中高的溶剂浓度有利于渗透蒸发单元的性能，从而导致更高的通量和渗透物中的总溶剂浓度。
