A process for the hydrocracking of light naphthas

Abstract

The application discloses a processing method of hydrocracking light naphtha. The method comprises the following steps: (1) mixing the hydrocracking light naphtha with hydrogen and passing the mixture through a hydroconversion reaction zone to perform a hydroconversion reaction; the hydroconversion reaction zone is filled with at least two hydroconversion catalyst beds, and the active metal content of the hydroconversion catalysts decreases in sequence along the flow direction; the hydroconversion catalysts comprise ZSM-5 molecular sieves; (2) performing high-pressure separation on the hydroconversion reaction effluent of step (1), using the hydrogen-rich gas obtained by separation as circulating hydrogen, and feeding the liquid-phase effluent into a separation system to obtain ethane, propane and n-butane. According to the method, the isomeric alkanes in the hydrocracking light naphtha can be efficiently converted into ethane, propane and n-butane, the separated isobutane can be recycled to the hydroconversion reaction zone for further cracking, and the yield of small-molecule n-alkanes in the product is greatly improved.

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