Sugar cane bagasse as feedstock for second generation ethanol production. Part II: Hemicellulose hydrolysate fermentability
Sugar cane bagasse as feedstock for second generation ethanol production. Part II: Hemicellulose hydrolysate fermentability
复制标题
DOI：
10.2225/vol13-issue5-fulltext-8
复制
发表时间：
2010-09-15
影响因子：
2.7
通讯作者：
Pereira, Nei, Jr.
中科院分区：
文献类型：
--
作者：
Betancur, Gabriel J. Vargas;Pereira, Nei, Jr.
甘蔗渣在巴西作为制糖和乙醇工业的废物产生。这种木质纤维素材料是第二代乙醇生产的潜在来源;然而，预处理阶段是必不可少的，其目的是通过破坏木质纤维素复合物来去除半纤维素组分。本研究以甘蔗渣为原料，采用稀酸水解法对甘蔗渣进行预处理，得到富含木糖的水解产物，并利用树干毕赤酵母进行发酵生产乙醇。采用统计学方法研究了稀酸水解工艺中酸浓度、固液比和暴露时间等因素对不同水解液发酵性的影响。统计分析有助于确定单个因素及其相互作用对响应变量的影响。确定了甘蔗渣半纤维素酶解液发酵生产乙醇的最佳预处理条件为：酸浓度1.09%（v/v）、固液比1：2.8（g：ml）、发酵时间27 min。在这些条件下，获得具有50 g/l木糖、6.04 g/l乙酸、0.55 g/l羟甲基糠醛和0.09 g/l糠醛的水解产物，并且其发酵在40小时内产生大约20 g/l乙醇。
Sugar cane bagasse is produced in Brazil as waste of the sugar and ethanol industries. This lignocellulosic material is a potential source for second-generation ethanol production; however a pretreatment stage is essential, which aims at removing the hemicellulose component by disorganizing the lignocellulosic complex. In this work sugar cane bagasse was pretreated by diluted acid hydrolysis resulting in xylose-rich hydrolysates, which could be fermented to ethanol by a strain of the yeast Pichia stipitis. Statistical approach was used to investigate the effects of factors associated with the diluted acid hydrolysis process (acid concentration, solid: liquid ratio and time of exposure) on the fermentability of different hydrolysates. The statistical analysis was useful for determining the effects of the individual factors and their interactions on the response variables. An acid concentration of 1.09% (v/v), a solid: liquid ratio of 1:2.8 (g:ml), and an exposure time of 27 min were established and validated as the optimum pretreatment conditions for ethanol production from hemicellulose hydrolysates of sugar cane bagasse. Under these conditions, a hydrolysate with 50 g/l of xylose, 6.04 g/l of acetic acid, 0.55 g/l of hydroxylmethylfurfural and 0.09 g/l of furfural was obtained and its fermentation yielded roughly 20 g/l of ethanol in 40 hrs.