生物质焦油催化裂解过程中酸性催化剂积碳失活与烧焦再生特性  

Deactivation and Burning Regeneration of Coked Acid Catalysts in Catalytic Cracking Process of Biomass Tar

作　　者：李永玲[1] 吴占松[2] 

机构地区：[1]北京科技大学机械工程学院,北京市海淀区100083 [2]清华大学热科学与动力工程教育部重点实验室,北京市海淀区100084

出　　处：《中国电机工程学报》2014年第8期1297-1303,共7页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51306017);中央高校基本科研业务费专项项目(FRF-MP-13-005B;FRF-SD-12-007B)~~

摘　　要：为了研究酸性催化剂积碳失活以及再生特性,在固定床反应器上,以高铝砖作为催化剂,进行了生物质焦油催化裂解实验。实验结果表明,由于催化剂表面积碳,造成催化剂活性随着作用时间增加而下降。但当催化剂工作一定时间后,催化剂表面的积碳速率开始变得平缓,单层积碳向多层积碳转变。当积碳速率与反应中焦炭脱除速率达到平衡时,催化剂表面积碳量将趋于稳定。实验中采用烧焦法有效地恢复了催化剂的活性,但是焦炭燃烧会破坏催化剂表面的酸性结构,减少表面活化位,使得再生后的催化剂并不能完全达到新鲜催化剂所具有的催化能力。而且烧焦再生过程中会发生烧结,结晶等现象,改变催化剂的孔隙率、孔径分布、比表面积等物理特性。In order to study the activity regeneration of deactivating acid catalysts with carbon deposition, the catalytic cracking experiments on biomass tar were carried out in a fixed bed reactor with high-alumina brick as acid catalyst. The results show that the catalyst activity declines with the increase of reaction time, due to the carbon depositing on catalyst surface. The carbon depositing rate on catalyst surface becomes smooth after a period of work time, and the mode of coke deposition becomes multi-layer form monolayer. The quantities of the carbon depositing on the catalyst surface will be stable, when the coking rate is equal to the rate of coke consumption. The regeneration method of coke burning can effectively recover the activity of catalyst. But the activity of regenerated catalyst cannot be the same as that of fresh catalyst, because the acidic structure and active center on catalyst surface are destroyed in coke combustion process. In addition, the sintering or crystallization phenomenon will occur in catalysts regeneration process with coke burning, which may change the physical characteristics of catalyst, such as porosity, pore size distribution, specific surface area, and so on.

关 键 词：生物质焦油 催化裂解 酸性催化剂 活性中心 失活 再生 

分 类 号：TQ524[化学工程—煤化学工程]