Synthesis of hierarchical ZSM-5 microspheres with superior performance for catalytic methanol-to-olefin conversion
Zhang Yali1, Zhang Kai2, Shang Chao1, Wang Xiaoning1, Wu Lei1 , Huang Guoqing1 , Wang Hao1, Sun Qiming2, Chen Xiao Dong1,*（陈晓东）, Wu Zhangxiong1,*（吴张雄）
1 Particle Engineering Laboratory, School of Chemical and Environmental Engineering,College of Chemistry, Chemical Engineeringand Materials Science, Soochow University,Suzhou, People's Republic of China
2 Innovation Center for Chemical Sciences, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, People's Republic of China
AIChE J. 2023; 69: e17913.
Methanol-to-olefin (MTO) conversion on zeolites has encountered severe coke depo-sition and rapid deactivation. Creating different levels of porosity is essential to miti-gate such issues. Herein, we demonstrate a facile and green strategy to synthesizeuniform and hierarchically macro/mesoporous ZSM-5 microspheres by combiningspray-freeze drying and steaming-assisted crystallization (SAC). The structure, crys-tallinity, and porosity of the zeolite microspheres are controlled by adjusting thewater/gel mass ratio and time in the SAC process. The structure evolution during theSAC process is revealed. In the catalytic MTO reaction, the representative hierarchi-cally porous ZSM-5 catalyst exhibits superior catalytic performance. At a very highweight hourly space velocity of 18 h1, it shows a dramatically prolonged lifetime(47 h at >99% conversion) and much-improved selectivity to ethylene and propylenecompared with the conventional microporous ZSM-5 and nano-sized ZSM-5. Theenhanced performance is originated from the hierarchical structure and suitable acid-ity of the ZSM-5 microsp.
链接：//aiche.onlinelibrary.wiley.com/doi/full/10.1002/aic.17913
