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针对胜利褐煤焦水蒸气气化反应过程中钙组分的催化作用,在脱除矿物质胜利褐煤煤样SL+中添加CaO在1100℃热解得到添钙煤焦样品Ca-J,Ca-J经盐酸处理脱除其游离钙组分,得到添钙焦酸洗煤样Ca-J+,采用BET、SEM-EDS、XRD、FT-IR及XPS等技术对所制备煤样进行表征,并在微型固定床反应装置上进行水蒸气气化反应性测试,对煤样微结构特性进行研究,提出了钙催化水蒸气气化反应中的活性微结构模型。结果表明,水蒸气气化反应中,添钙焦样酸洗前后的Ca-J和Ca-J+碳转化率及反应活性指数基本相同,但比酸洗煤焦样 SL+-J高出许多。样品 XPS的 Ca 2p谱图分峰说明,Ca-J+中存在Ca( CH3 COO)2与Ca-OOR两种化学形态的钙。化学分析及SEM-EDS表征均表明,Ca-J+中钙含量比Ca-J减少了97%以上；XRD表明,Ca-J中游离存在的CaS、CaO经酸洗被脱除；FT-IR表明,Ca-J及Ca-J+中含有C=O、C-O等特征吸收峰。综合上述结果,可推测“R-O-Ca-O-R＇”( R及R＇可为脂肪族或芳香族结构体)是钙组分催化胜利褐煤焦水蒸气气化的活性微结构。,The catalytic effect of calcium component on steam gasification of Shengli lignite char was studied. Demineralized coal samples were loaded with calcium oxide and pyrolyzed at 1 100℃ ( Ca-J ) . Ca-J+ was prepared from Ca-J treated by hydrochloric acid. The char samples were characterized by BET, SEM-EDS, XRD, FT-IR and XPS. The steam gasification of the char samples was performed in a micro fixed bed reactor. The possible catalytic active micro structure was discussed and proposed. The results show that carbon conversion and reactivity index of Ca-J and Ca-J+ samples during steam gasification were substantially similar, but much higher than those of demineralized char samples (SL+-J). Ca(CH3COO)2 and Ca-OOR, two calcium species are present in Ca-J+ sample determined by XPS. Chemical analysis and SEM-EDS prove that calcium content of Ca-J+ decreases by more than 97% than that of Ca-J sample. XRD analysis indicates free inorganic mineral ( CaS, CaO) is removed by hydrochloric acid. FT-IR spectra show C=O, C-O peaks present in Ca-J and Ca-J+samples. So it is postulated that “R-O-Ca-O-R’” ( R and R’are aliphatic and aromatic structures, respectively) is the catalyst active microstructure during char steam gasification.