| 摘要 |
Provided herein are hybrid catalysts that are used in the deep catalytic cracking of petroleum naphthas or other hydrocarbon feedstocks, for the selective production of light olefins, in particular ethylene and propylene and BTX aromatics. The hybrid catalysts of this invention contain a chemically treated microporous crystalline silicate such as the pentasil-type silicalite, a mesoporous silica-alumina or zirconium oxide co-catalyst, into which may be incorporated aluminum oxide, molybdenum oxide, lanthanum oxide, cerium oxide or a mixture of aluminum and molybdenum oxides, and an inorganic binder such as bentonite clay. These novel catalysts show several advantages with respect to the classical steam (thermal) cracking: i) higher combined production of ethylene and propylene; ii) lower ethylene/propylene ratio; iii) much lower production of methane; iv) much lower reaction temperature resulting in significant energy savings; v) easy in-situ regeneration using air as oxidant; vi) lower carbon dioxide and other volatile oxides emitted during the regeneration phase.
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