State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technology, Nanjing, 210009, China.
Bioprocess Biosyst Eng. 2014 Feb;37(2):183-91. doi: 10.1007/s00449-013-0984-5. Epub 2013 Jun 4.
The effects of by-products from ethanol fermentation and hydrolysates of lignocelluloses on ethanol diffusion through polydimethylsiloxane (PDMS) membranes with/without silicalite-1 were investigated. A pervaporation process was integrated with lignocellulosic fermentation to concentrate bioethanol using bare PDMS membranes. Results showed that yeasts, solid particles, and salts increased ethanol flux and selectivity through the membranes (PDMS with/without silicalite-1), whereas glucose exerted negative effects on the performance. On bare PDMS membrane, the performance was not obviously affected by the existence of aliphatic acids. However, on PDMS-silicalite-1 membrane, a remarkable decrease in ethanol selectivity and a rapid growth of total flux in the presence of aliphatic acids were observed. These phenomena were due to the interaction of acids with silanol (Si-OH) groups to break the dense membrane surface. On the PDMS membranes with/without silicalite-1, degradation products of lignocellulosic hydrolysates such as furfural and hydroxyacetone slightly influenced separation performance. These results revealed that an integrated process can effectively eliminate product inhibition, improve ethanol productivity, and enhance the glucose conversion rate.
研究了乙醇发酵副产物和木质纤维素水解产物对含有/不含有 silicalite-1 的聚二甲基硅氧烷（PDMS）膜中乙醇扩散的影响。将渗透汽化过程与木质纤维素发酵相结合，使用裸 PDMS 膜浓缩生物乙醇。结果表明，酵母、固体颗粒和盐通过膜（含有/不含有 silicalite-1 的 PDMS）增加了乙醇通量和选择性，而葡萄糖对性能产生了负面影响。在裸 PDMS 膜上，脂肪酸的存在对性能没有明显影响。然而，在 PDMS-silicalite-1 膜上，存在脂肪酸时，乙醇选择性显著下降，总通量迅速增加。这些现象是由于酸与硅醇（Si-OH）基团相互作用破坏了致密的膜表面。在含有/不含有 silicalite-1 的 PDMS 膜上，木质纤维素水解产物的降解产物如糠醛和羟基丙酮对分离性能的影响很小。这些结果表明，集成工艺可以有效地消除产物抑制，提高乙醇生产率，并提高葡萄糖转化率。
