摘要
为考察超低浓度马来酸对玉米芯纤维素的水解性能,该文采用高温液态水预处理和超低马来酸水解相结合的两步法。3,5-二硝基水杨酸(DNS)比色法和高效液相色谱法(HPLC)分析表明,第一步预处理(200℃,10min,4MPa,500r/min,液固比20:1mL/g)玉米芯可获得12.24g/L还原糖,半纤维素转化率91.76%,损失3.61%的纤维素;其残渣进行第二步酸水解(质量分数0.1%,220℃,20min,4MPa,500r/min,液固比20:1mL/g)可获得9.94g/L还原糖,纤维素转化率达95.17%,约1/3转化为糖。气相色谱-质谱联用(GC-MS)分析表明,第二步水解液中含有多种木质素降解副产物,如苯酚、苯甲酸等,带有多种活泼基团,可能与糖降解物反应,加快葡萄糖降解正反应的进行。改进反应器,使得糖降解物和木质素降解物及时排出,可提升马来酸水解性能,为马来酸在生物质水解领域的应用提供参考。
In order to investigate the hydrolysis characteristics of corn cob,two-step hydrolysis method of hot liquid water（HLW,to hydrolyze most of the hemicellulose and expose the cellulose）and extremely low concentration maleic acid（ELMA,to hydrolyze the cellulose to oligosaccharide and glucose）was approached.DNS and HPLC analyses indicated that there was 12.24 g/L reducing sugar in the hydrolysate of HLW（200℃,10 min,4 MPa,500 r/min,liquid-solid ratio 20：1 mL/g）,and 91.76%hemicellulose was dissolved in the water,with 3.61%cellulose loss;There was 9.94 g/L reducing sugar in the hydrolysate of ELMA（0.1%,220℃,20 min,4 MPa,500 r/min,liquid-solid ratio 20：1 mL/g）,and 95.17%cellulose was dissolved,but only about one-third converted to reducing sugar.By means of GC-MS,a large number of hydrolysis products of lignin were found in step two,such as phenol and benzoic acid compounds with active groups which can react with the sugar degradation products,to speed up the degradation of glucose.Some factors affecting the extremely low concentration maleic acid hydrolysis were studied,which can instruct rational better use of maleic acid hydrolysis.The hydrolysis performance of maleic acid can be promoted by improving the reactors to make degenerations of sugar and lignin discharged timely,which can provide a guidance for the application of maleic acid in biomass hydrolysis.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2012年第7期221-227,共7页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家科技支撑计划(2011BAD22B01)
国家自然科学基金(51176196)
中国科学院可再生能源与天然气水合物重点实验室基金(O907j7)
关键词
水解
纤维素
降解
超低马来酸
玉米芯
木质素
hydrolysis
cellulose
degradation
extremely low maleic acid
corn cob
lignin
