小晶粒β沸石表观聚结作用及机理研究

STUDY ON COAGULATION OF SMALL CRYSTAL BETA ZEOLITE AND ITS MECHANISM

采用聚沉剂对小晶粒β沸石胶体体系的表观聚结作用及其机理进行了研究。通过分析小晶粒β沸石在过滤体系中的存在状态,得到强碱性的胶态体系中小晶粒β沸石的胶团结构,并分析了反离子挤压Stern双电层时Zeta电势的变化,解释了小晶粒β沸石聚沉作用发生的原因。通过实验发现,当聚沉剂NS/小晶粒β沸石大于或等于30%(质量比)时,即发生常温聚沉,能大大提高过滤效率。聚沉后β沸石样品的相对结晶度有少许下降,同时能大幅度地降低样品的Na2O含量。经轻油微反评价其活性,说明聚沉后的β沸石仍是优良的烃类流化催化裂化(FCC)催化剂的活性添加组分。

The coagulation of the small crystal beta zeolite colloidal system in filtering system with the present of coagulating material NS and the mechanics of coagulation were studied The colloidal structure of beta zeolite particles in the filtering system, by means of analyzing its existence state, is recovered Meanwhile, the variation of Zeta electric potential, while the contra-ion extrudes Stern electric double layer, is analyzed, and the reason of coagulation is well explained It is found that the small crystal beta zeolite can coagulate at the room temperature when the ratio of NS to beta zeolite (net weigh) is not less than 30%, which can increase the filtering efficiency of little crystal beta zeolite greatly Relative crystallinity of beta zeolite coagulated by NS decreases a little, and the same time, the Na 2O percentage content of beta zeolite drops with wide range Experimental results provided by activity test on a light oil micro-test reaction apparatus state that beta zeolite coagulated by NS is also an excellent activity additive of FCC catalyst