乙酸常温预处理对木质纤维素厌氧消化的影响  

Impact of acetic acid pretreatment at normal temperature on the anaerobic digestion of lignocelluloses

作　　者：何品晶[1] 方文娟[1] 吕凡[1] 朱敏[1] 邵立明[1] 

机构地区：[1]同济大学环境科学与工程学院,污染控制与资源化研究国家重点实验室,长江水环境教育部重点实验室,上海200092

出　　处：《中国环境科学》2008年第12期1116-1121,共6页China Environmental Science

基　　金：国家自然科学基金资助项目(50708069);国家教育部科学技术研究重点项目(107122);上海-法国罗纳阿尔卑斯大区科研合作基金(06SR07105);上海市晨光计划(2007CG25)

摘　　要：采用3种稀酸组合(10%乙酸、10%乙酸加0.5%硝酸以及10%乙酸加0.5%磷酸),在常温条件下,对3种木质纤维素样品(滤纸、中性复印纸和无油墨报纸)进行预处理,分别考察预处理对生物质组成纤维素、半纤维素和木质素的作用.并选取预处理后的无油墨报纸进行厌氧消化实验,研究不同稀酸预处理方式对木质纤维素厌氧消化的影响.结果表明,酸处理组能水解5%±1%纤维素和88%±1%的半纤维素,但是不能水解木质素;乙酸预处理降低了木质纤维素的亲水性和生物可降解性,从而降低了初始厌氧消化效率.添加0.5%的磷酸或0.5%硝酸不会明显改善乙酸对木质纤维素的水解效果.但是,添加磷酸的处理组在厌氧消化初期微生物量较少的情况下,能为微生物生长提供磷元素,有利于厌氧消化的启动;而添加硝酸的处理组不能缓解预处理对木质纤维素基质性质的影响,而且导致了丙酸的大量积累,从而恶化了厌氧消化的效果.Three kinds of lignoceUuloses samples （filter paper, office paper and newspaper） were pretreated with three kinds of acids （10% acetic acid, 10% acetic acid with 0.5% nitric acid and 10% acetic acid with 0.5% phosphoric acid） at normal temperature, to investigate the impact of acid pretreatment on the hydrolysis of biochemical components （cellulose, hemicellulose and lignin） separately. The effect of acid pretreatments on the anaerobic digestion of lignocellulose was evaluated with pretreated newspaper. 5%±1% of cellulose and 88%±1% of hemicelluloses could be hydrolyzed by acid treatment, but not lignin. Acetic acid pretreatment decreased the hydrophilicity and biodegradability of lignocellulose, causing impact on anaerobic digestion. 0.5% nitric acid or 0.5% phosphoric acid added played little significant effect on hydrolysis. However, even at the early stage, when the microbial biomass was less, anaerobic digestion could be also maintained while pretreated with phosphoric acid added. And phosphoric acid could provide the phosphorus element for microbial growth, hence phosphoric acid added was conducive to the startup of anaerobic digestion. Addition of nitric acid could not ease the impact of property changes of lignocelluloses caused by pretreatment. Furthermore, nitric acid caused the accumulation of propionic acids, thereby worsening the effect of anaerobic digestion.

关 键 词：乙酸 预处理 木质纤维素 厌氧消化 分子量分布 

分 类 号：X705[环境科学与工程—环境工程]