摘要
磷酸是潜在的预处理溶剂,可应用于以木质纤维素为原料来生产生物乙醇或生物基化学品的工厂.实验样品按下述方法准备:分别控制温度在30℃、50℃、70℃下,微晶纤维素溶解于浓度为83.03%的磷酸中;作用10小时,每隔30分钟取一次样.经X-射线衍射技术检测发现样品的结晶衍射峰显著降低,相应的结晶度也呈显著下降趋势.较高的温度可以促进纤维素在磷酸中的溶解,在较低的温度下,纤维素在磷酸中溶解的动力学行为遵循动力学方程:ln1/(1-Tt)kr.在温度30℃、50℃、70℃下,磷酸对纤维素解结晶反应的常数分别为0.059 5 h-1、0.165 0 h-1、0.116 3 h-1,活化能为42.40 kJ/moL.
Phosphoric acid was a potential pretreatment solvent of lignocellulose in mills of bio-ethanol or biobased chemicals.Microcrystalline cellulose（MCC） was dissolved in phosphoric acid（the concentration was 83.03%） for 10 hours at temperatures of 30,50,70 ℃,samples were prepared every 30 minutes.XRD analysis showed the crystalline diffraction peaks decreased much,and the corresponding crystalline degree also induced markedly.The high temperature accelerated the rate of cellulose dissolving in phosphoric acid.At the relative low temperature,the kinetic behaves of cellulose dissolving in phosphoric acid obeyed the kinetic equation of ln11-Ttkt well,the constants of decrystallization reactions at the temperatures of 30,50,70 ℃ were 0.059 5,0.165 0,0.116 3 h^-1,the activation energy was 42.40 kJ/mol.
出处
《陕西科技大学学报（自然科学版）》
2010年第5期7-12,共6页
Journal of Shaanxi University of Science & Technology
基金
国家自然科学基金项目(50776035,U0733001)
教育部博士点基金(20070561038)
创新团队研究计划(IRT0552)
863计划(2007AA052408)
国家科技支撑计划(2007BAD34B01)资助项目
关键词
动力学方程
溶解
磷酸
kinetic equation
dissolving
phosphoric acid
作者简介
张景强（1974-），男，四川省西昌市人，博士，研究方向：分析化学与生物质精炼
