Elsevier, Wu Ji Cai Liao Xue Bao ==, 3(31), p. 248
DOI: 10.15541/jim20150363
Full text: Unavailable
B-ZSM-5/EU-1 composite zeolite was synthesized with different hydroxides as alkaline materials. It was found that guiding role of sodium was the strongest by comparing structure-directing effect and appearance characteristics. The surface of B-ZSM-5/EU-1 composite zeolite was smooth without obvious crystal limits. The synthetic samples were investigated by TG-DTG, N-2 adsorption-desorption and NH3-TPD. The results show that the template weight loss rate of dual-mode-one-step composite zeolite is 5.67%, which is lower than that of mechanical composite zeolite (7.31%). The specific surface area, pore volume and microporous average pore size have significantly enlarged, meanwhile the amount and strength of acid have also increased, which will be favorable for the aromatization trend of methanol and the priority diffusion of xylene from the composite zeolite. The performance of the composite zeolite catalyst was evaluated in conversion of methanol to xylene. The results show that the selectivity of aromatics in the oil phase reaches 66.72% by using a dual-mode composite zeolite as a catalyst, of xylene in the aromatics reaches 46.15%, and of p-xylene in the xylene reaches 30.75%. The above results can be attributed to special pore structure for the catalytic reaction, which benefits for the priority diffusion of xylene with a smaller particle size from the B-EU-1/ZSM-5 zeolite.