焦油组分重整过程中关键反应的机理研究  

Mechanism investigation of key reactions during tar component reforming process

作　　者：杜文亚 于震宇 郭锐 孙超 邵正日 谢华清 Du Wenya;Yu Zhenyu;Guo Rui;Sun Chao;Shao Zhengri;Xie Huaqing(Chongqing CISDI Thermal&Environmental Engineering Co.Ltd.,Chongqing 401120,China;School of Metallurgy,Northeastern University,Shenyang 110819,China;Liaoning Provincial Key Laboratory of Energy Storage and Utilization,Yingkou Institute of Technology,Yingkou 115014,China)

机构地区：[1]重庆赛迪热工环保工程技术有限公司,重庆401120 [2]东北大学冶金学院,辽宁沈阳110819 [3]营口理工学院辽宁省储能与能源利用技术重点实验室,辽宁营口115014

出　　处：《可再生能源》2024年第4期440-447,共8页Renewable Energy Resources

基　　金：辽宁省储能与能源利用技术重点实验室基金项目(CNWK202305)。

摘　　要：采用密度泛函理论计算方法,对焦油重整过程中主要发生的C-C键裂解反应、CH_(4)重整反应和水煤气转化反应的机理和能量变化进行探究。结果表明:在C-C键裂解反应中,C_(3)H_(8)首先吸附于催化剂表面形成吸附态C_(3)H_(8)*,进一步裂解生成CH_(3)*和CH_(2)CH_(3)*,裂解反应放热,但是反应能垒较大,较难进行;在CH_(4)重整反应中,CH_(4)*发生顺序脱氢反应生成CH_(3)*,CH_(2)*,CH*,相比于继续脱氢,CH*更倾向于与OH*发生重整反应生成CHO*,CHO*脱氢生成CO*,各步骤产生的H*结合生成H_(2)*,CH_(2)*裂解生成CH*的反应为CH_(4)重整反应的限速步骤;在水煤气转化反应中,H_(2)O*分解后生成的OH*更倾向于与CO*结合生成COOH*,而不是直接与H*生成H_(2)*,COOH*脱去H,生成COO*,该反应为限速步骤。Density functional theory calculations were employed to investigate the mechanisms and energy changes involved in C-C bond cracking,CH_(4)reforming,and water gas shift reactions in the tar reforming process.The findings reveal that,in the C-C bond cracking reaction,C_(3)H_(8)initially adsorbs onto the catalyst surface to form adsorbed C_(3)H_(8)*,subsequently undergoing cleavage to produce CH_(3)*and CH_(2)CH_(3)*.While the cracking reaction is exothermic,it is hindered by a significant energy barrier and difficult to carry out.In the CH_(4)reforming reaction,CH_(4)*undergoes sequential dehydrogenation reactions,producing CH_(3)*,CH_(2)*,and CH*.Comparatively,CH*has a greater tendency to react with OH*to form CHO*,which further undergoes dehydrogenation to form CO*.Additionally,H*generated in each step combines to form H_(2)*.Throughout the CH_(4)reforming process,the rate-limiting step is the cracking of CH_(2)*to CH*.In the water gas shift reaction,the OH*species formed from H_(2)O*decomposition prefers to combine with CO*to generate COOH*rather than directly reacting with H*to produce H_(2)*.COOH*removes H and generates COO*,which is the rate limiting step.

关 键 词：焦油 重整 密度泛函理论 基元反应 

分 类 号：TK6[动力工程及工程热物理—生物能]