高变质程度无烟煤热天平水蒸气催化气化动力学(Ⅰ)碳酸钠催化剂  

Catalytic gasification kinetics of high metamorphosed anthracites by steam in thermogravity(Ⅰ) With sodium carbonate as catalyst

作　　者：林荣英[1] 张济宇[2] 

机构地区：[1]中国科学院山西煤炭化学研究所,山西太原030001 [2]福州大学化学工程技术研究所,福建福州350002

出　　处：《化工学报》2006年第10期2309-2318,共10页CIESC Journal

基　　金：国家自然科学基金项目(20376014);福建省科技厅重点项目(HG99-01).~~

摘　　要：以碳酸钠为催化剂,用热天平的等温热重法研究了4种高变质程度无烟煤（挥发分含量Vad=2.69%～4.35%）常压下纯水蒸气催化气化反应动力学.在加和不加Na2CO3条件下,测定了温度为750～950℃无烟煤的化学反应控制条件下的转化率与时间的关系.加Na2CO3的转化率与时间的关系用缩芯模型和修正体积模型进行了良好的拟合关联,得出这4种高变质程度无烟煤水蒸气催化气化反应的反应速率常数、活化能和指前因子,按反应速率常数表示的反应活性大小顺序为：永安丰筛＞永安加筛＞上京煤＞永定煤,活化能范围：147.70～199.79 kJ·mol-1.与不加催化剂的结果相比,加Na2CO3的具有更小的活化能和指前因子,低温（750～850℃）时催化效果更明显.Using sodium carbonate as catalyst, steam gasification kinetics of four high metamorphosed anthracites （Vad = 2.69%～4.35%） were investigated with isothermal thermogravimetric analysis under ambient pressure. With and without Na2CO3 catalyst, the relationships of conversion （x） with reaction time （t） for these anthracites were obtained within the temperature range from 750℃ to 950℃ under reaction control. The shrinkingcore model and modified volumetric model were used to correlate the relations between x and t for the case with Na2CO3 as catalyst. The reaction rate constants （k） at different temperatures were determined. The reaction activation energy （Ea） and the pre-exponential factor （k0） were predicted from the Arrhenius equation. According to the order of k determined by the above two models, the order of activity of the four anthracites was as follows： Yong＇an Fengshai coal Yong＇an Jiashai coal 〉Shangjing coal〉Yongding coal. Also, the Ea, ranging from 147.70 kJ· mol^-1 to 199.79 kJ·mol^-1 , were estimated by this study. Comparing with the case without catalyst, the Ea and the k0 of the case with Na2CO3 as catalyst were smaller and the catalytic effect was more obvious when the temperature was lower than 850℃.

关 键 词：等温热重法 碳酸钠水蒸气催化气化 高变质程度无烟煤 反应动力学 

分 类 号：TQ54[化学工程—煤化学工程]