CO_(2)气氛下生物质焦炭颗粒催化气化表观动力学研究

Study on catalytic gasification epigenetic dynamics of coke particles under CO_(2) atmosphere

将催化剂CaO、Fe_(2)O_(3)和Na_(2)CO_(3)负载至焦炭颗粒内部,利用等温失重法进行焦炭颗粒气化动力学实验,确定CO_(2)气氛下焦炭气化反应机理函数;并通过SEM和比表面积分析,探究催化剂对焦炭表面和内部形貌的影响。结果表明,在CO_(2)气氛下,生物质焦炭颗粒气化遵循收缩圆柱体模型,并通过对lnA和活化能(E)线性拟合,遵循动力学补偿效应。三种催化剂都能够增大焦炭的比表面积,对焦炭形貌变化起到不同程度的影响,都能降低气化反应活化能,对反应起到明显的催化作用,其催化作用强弱顺序为Na_(2)CO_(3)>CaO>Fe_(2)O_(3)。

The catalyst(CaO,Fe_(2)O_(3) and Na_(2)CO_(3))was loaded into the coke particles.The mechanism of the gasification reaction of coke in the atmosphere of CO_(2) was determined by using the isothermal weight loss method to test the gasification kinetics of the coke particles.The coke was measured by SEM and specific surface area analysis,and the effect of catalyst on the surface and internal morphology of coke was investigated.The results show that in CO_(2) atmosphere,biomass coke particle gasification follows the shrinking cylinder model,and through linear fitting of ln A and activation energy E,follow the dynamic compensation effect.The three catalysts can increase the specific surface area of the coke and find that the catalyst has a varying degree of influence on the change of the morphology of the coke during the reaction.The activation energy of the gasification reaction can be reduced by three kinds of catalysts,and the reaction plays an obvious catalytic role,and the catalytic activity of the three catalysts is Na_(2)CO_(3)>CaO>Fe_(2)O_(3).