催化气化过程中Na催化剂失活与Na-Al复合转化行为  

Na catalyst deactivation and Na-Al reaction and transformation behaviorsduring catalytic gasification

作　　者：梅艳钢 高松平 张乾[2] MEI Yangang;GAO Songping;ZHANG Qian(Department of Chemistry and Chemical Engineering,Taiyuan Institute of Technology,Taiyuan 030001,China;State Key Laboratory of Clean and Efficient Coal Utilization,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原工业学院化学与化工系,山西太原030001 [2]太原理工大学省部共建煤基能源清洁高效利用国家重点实验室,山西太原030024

出　　处：《洁净煤技术》2023年第3期85-91,共7页Clean Coal Technology

基　　金：山西省基础研究计划-青年科学研究资助项目(202103021223350);煤科学与技术教育部重点实验室开放课题资助项目(MKX202102)。

摘　　要：催化气化是一种新型煤气化方式,催化气化催化剂主要为碱金属催化剂,但在催化气化过程中碱金属催化剂会与煤中Si、Al矿物质相互反应,直接影响碱金属催化气化催化活性。以Na_(2)CO_(3)为催化剂,分析催化气化过程中碱金属失活行为与Na-Al复合转化行为,采用高岭石和勃姆石为模型化合物对Na-Al复合与转化过程进行研究,并对比Na-Al转化产物的催化作用。研究表明:Na_(2)CO_(3)催化作用良好,催化气化过程中Na_(2)CO_(3)与煤中Si、Al矿物质反应,生成霞石与硅铝酸钠类物质,导致催化剂失活。高岭石与Na_(2)CO_(3)在700℃开始反应,生成硅铝酸钠类物质。勃姆石与Na_(2)CO_(3)在860℃时反应生成偏铝酸钠,偏铝酸钠高温下不稳定,进一步转化为硅铝酸钠类物质。与Na_(2)CO_(3)相比,硅铝酸钠与偏铝酸钠的催化效果较差,导致碱金属催化作用下降,同时,生成的偏铝酸钠催化效果优于硅铝酸钠。Catalytic gasification is a new type of coal gasification method,and the catalysts used in catalytic gasification are usually alkali metals.However,in catalytic gasification process,alkali metal catalysts react with Si and Al minerals in coal,directly affecting the catalytic activity of alkali metal in catalytic gasification.The deactivation behaviors of alkali metals and Na-Al reaction and transformation during catalytic gasification with Na_(2)CO_(3) addition was studied.Kaolinite and boehmite were used as model compounds to study the Na-Al reaction and conversion process,and the catalytic effects of Na-Al conversion products were compared.The study shows that Na_(2)CO_(3) has good catalytic effect.During catalytic gasification,Na_(2)CO_(3) reacts with Si and Al minerals in coal to form nepheline and sodium aluminosilicate,resulting in catalyst deactivation.Kaolinite reacts with Na_(2)CO_(3) at 700℃to form sodium aluminosilicates,and boehmite reacts with Na_(2)CO_(3) at 860℃to form NaAlO_(2),which is unstable at higher temperature and is converted into sodium aluminosilicates.Compared with Na_(2)CO_(3),the catalytic effect of sodium aluminosilicates and NaAlO_(2) is poor,resulting in the deactivation of Na_(2)CO_(3),and the catalytic effect of NaAlO_(2) is better than that of sodium aluminosilicates.

关 键 词：催化气化 矿物质 催化剂失活 碱金属失活 

分 类 号：TQ546[化学工程—煤化学工程]