Effects Of Aging Methods On The Synthesis Of SSZ-13 Zeolite

SSZ-13 zeolite has been identified as a kind of effective material for catalysts and membranes because of its unique structure,but the long crystallization time is the main obstacle for its industry application.This paper introduced ultrasonic technology and high shear technology for the sol aging,optimized the related condition,and explored the effects of shortening the synthesis period and their influence on SSZ-13physical properties and the crystallization process.The samples were characterized with XRD,SEM,BET,FTIR,NMR and TG-DSC for the analysis.And the main results are as follows:1.The optimal conditions of ultrasonic aging are:0.25 W/cm~2 for the ultrasonic power and 30 min for the ultrasonic time.Under the condition of ultrasonic processing,the crystallinity of SSZ-13 zeolite gained 98.3%within 72 h,and the time needed shortened 48 h compared with the traditional hydrothermal synthesis method.Expect of keeping the shape and structure,ultrasonic aging made zeolite SSZ-13 have higher specific surface area and silica alumina ratio.2.The optimal conditions of high shear is:10000 rpm for the speed and 15 min for the high shear time.Under the condition,the crystallinity of SSZ-13 zeolite gained98.3%within 48 h.Thus,60%of the crystallization time was saved compared with the traditional hydrothermal synthesis method and 33.3%compared with the ultrasound aging method.Beside that,the molecular sieve kept the original shape and structure.