Bi-phases Composite Zeolites FAU@nano-ZSM-5 Prepared By A Vapor Phase Method

Y zeolite and its modifiers, in the petrol-processing industrial fields, have been all-important catalytic materials on account of their excellent catalytic performances exhibiting in petrochemical field. The catalytic performance of catalysts revealed the close relationship with preparation and modification of zeolite. In this article, composites had been prepared based on Y zeolite by incorporating ZSM-5 zeolite through vapor phase method. The crystalline, structural, textural property and catalytic activity of the composite materials were characterized by XRD, FT-IR, nitrogen adsorption-desorption techniques, SEM, NH3-TPD and the cracking reaction of cumene.A certain amount of NaY@C carbon-coated material, pretreated by carbon coating with glucose, was added to the ZSM-5 gel solution, then followed by mixing and drying. A zeolite-zeolite composite composed of Y and ZSM-5 zeolite was successfully prepared by the vapor phase method. The results display that carbon coating treatment to Y zeolite effectively avoids the ZSM-5 alkaline gel solution damaging to the framework of Y zeolite, which lead to Change the optimal synthetic environment of ZSM-5 zeolite. The consequence shows that the synthesis of composite molecular sieves is affected by the crystallization time, alkalinity of gel solution and the amount of ammonia. In the process of steaming-treated, Aluminum species are extracted from the framework of Y zeolite, which leads to enlarging its silicon/aluminum ratio and introducing of the hierachical pores. The results of catalytic cracking of cumene shows that the introduction of hierachical pores in the composite molecular sieves can not only improve the diffusion rate of material in pore channels, but also improve the accessibility of the acid sites, thereby reducing the probability of coking carbon deposition over activity center and eventually increasing the conversion rates and extending its stability. Regulating the composition ratio of Y and ZSM-5 two-phase zeolite can efficiently adjust the oil/Ene ratio in catalytic cracking reaction of heavy oil, which provides a potential and efficient catalysts for catalytic cracking of heavy oil. Bi-phases composite zeolites Y@nano-ZSM-5 was prepared by the vapor phase method, which offers a new and efficient synthesis method for preparation of composite zeolites.