Rare earth metal exchanged Y-type zeolite

A. R. Songip, T. Masuda, H. Kuwahara, and K. Hashimoto, Production of high quality gasoline by catalytic cracking over rare-earth metal exchanged y-type zeolites of heavy oil from waste plastics. Energy and Fuels, 8, 136 (1994). 

Nickel is a well-known catalyst component and is thought to play an important role in the transformation of the hydrogen of steam to hydrocarbons. Hence, a part of the rare earth metal in REY is exchanged with Ni to become prepared Ni and the rare earth metal-exchanged Y-type zeolite catalyst (Ni-REY) [14, 15]. The physical and chemical properties of the catalysts are listed in Table 6.8. The polyethylene plastics-derived heavy oil shown in Table 6.2 was used as the feed oil. 

The most widely used conventional chemical methods are pyrolysis [21-25] and catalytic cracking [13, 26-30], The latter yields products with a smaller range of carbon numbers and of a higher quality than products generated by the former method. Several types of solid acid catalysts, which are known to be effective for catalytic cracking (e.g. HZSM-5, HY and rare earth metal-exchanged Y-type (REY) zeolite and silica-alumina (SA)) were evaluated by catalyst screening tests and are listed in Table 6.1. The acidic... 

A rare earth metal-exchanged Y-type (REY) zeolite catalyst was found to be an effective catalyst for the catalytic cracking of heavy oil. The influence of the reaction conditions and the catalytic properties of REY zeolite on the product yield and on gasoline quality have been described above. In this section, a reaction pathway is proposed for the catalytic cracking reaction of heavy oil, and a kinetic model for the cracking reaction is developed [14,33]. 

An inspection of the industrial use of zeolites as catalysts shows, however, that only a rather limited number of zeolite topologies are currently used in major industrial processes. Among the more important ones are ultrastable Y (USY) (FAU), rare-earth-exchanged faujasite-type (X, Y) (FAU) andZSM-5-type (MFI) zeolites in fluid catalytic cracking (FCC) of oil fractions [4] noble-metal-loaded U SY for hydroisomerization and hydrocracking of naphtha feedstocks [5] mordenite (MOR) and zeolite Omega (MAZ) -based catalysts for C4-C6 alkane isomerization [6] zeolites ZSM-23 (MTT), ZSM-35 (FER), ZSM-5 for selective oil dewaxing [7] ZSM-5, silicalite (MFI), MCM-22 (MWW), Beta-type (BEA) zeolites for aromatics alkylation to yield ethylbenzene, p-xylene. 

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