改性无纺布-壳聚糖固定化酵母生产燃料乙醇

Chloroepoxy propane modified nonwoven-chitosan immobilized yeast for fuel alcohol production

采用含酵母的壳聚糖溶液经木质素磺酸钠交联的方法包埋固定化在环氧氯丙烷改性的聚丙烯无纺布上。以甘蔗废糖蜜为原料,研究固定化酵母的发酵及增殖机理发现,酵母包埋量达3.7×109/mL,在批式发酵中,初始糖质量浓度167 g/L、填充率12%、pH 4.0、温度34℃时,发酵成熟醪酒精质量浓度达78.2 g/L、残糖质量浓度12.8 g/L、发酵周期缩短至10.5 h。连续流动发酵实验中,材料使用40 d没有破损,乙醇发酵过程彻底,速率快,残糖水平低,原料利用率和发酵醪乙醇浓度均超过传统工艺。

Chitosan embedded with yeast is cross linked through sodium lignosulphonate with the polypropylene （PP） nonwoven modified with chloroepoxy propane. The fermentation effects of material composite, shapes, initial concentration, and packing ratio of immobilized yeast are studied. The immobilized yeast has a biological capacity of 3.7 × 10^9/mL. The results show that the maximal ethanol concentration, residual sugar concentration, and the fermentation time of the immobilized yeast are 78.2 g/L, 12.8 gilL and 10.5 h, respectively, when the sugar concentration, packing ratio, pH, and the temperature are 167 g/ L, 12 % ,4.0 and 30℃, respectively. In 40 days of the continuous fermentation process the results of immobilized yeast remains stable without significant change of membrane shape and size. The experiments show that the immobilized yeast of polypropylene （PP） nonwoven-based chitosan has higher cartier ethanol productivity, lower residual sugar concentration, and can get a higher conversion ratio of material and ethanol concentration than thosewith the traditional technology.