Method for preparing cyclopentane by hydrogenation of cyclopentadiene or preparing methyl cyclopentane by hydrogenation of methyl cyclopentadiene

Abstract

A method for preparing cyclopentane by hydrogenation of cyclopentadiene or preparing methyl cyclopentane by hydrogenation of methyl cyclopentadiene is performed in a lower-feeding type adiabatic bubbling fixed bed reactor, the lower-feeding type adiabatic bubbling fixed bed reactor provided with 2 ~ 10 bed layers, and each bed layer is filled with a catalyst; the method is performed in the following continuous feed mode: raw materials of the cyclopentadiene or the methyl cyclopentadiene and hydrogen are introduced into respectively from a lower bed layer; a hydrogenated material coming out from the reactor top is cooled by a first heat exchanger and then enters into a gas-liquid separation tank, a liquid phase material in the gas-liquid separation tank is collected by a bottom reflux pump; the collected material is further cooled through a second heat exchanger, one stream of the cooled material is used as a product and is collected by a product collecting control valve, the rest streams of the cooled material are used as cyclopentadiene or methyl cyclopentadiene diluents, and are returned back to the lower part of each bed layer by respective flow control valves, and according to the returning amount of each stream, a corresponding bed layer is controlled to be heated. According to the method, cyclopentane or methyl cyclopentane is high in yield, low in sulfur content, and less in by-products, technological operation is flexible, and the operation cycle of the catalyst is long.

Description

technical field [0001] The invention relates to a method for producing cyclopentane by hydrogenation of cyclopentadiene or hydrogenation of methylcyclopentadiene to produce methylcyclopentane, in particular to the separation of C5 fractions in the by-products of ethylene produced by cracking petroleum hydrocarbons The cyclopentadiene or cracking dicyclopentadiene in the cracked carbon nine cuts is decomposed to obtain a method for cyclopentadiene hydrogenation to produce cyclopentane, the method produces cyclopentane or methylcyclopentane with high yield and low sulfur content Low, less by-products, flexible process operation, and long service life of the catalyst. Background technique [0002] As a new foaming agent for rigid polyurethane foam, cyclopentane is used to replace chlorofluorocarbons (CFCS), which have a damaging effect on the atmospheric ozone layer. It has been widely used in the production of fluorine-free refrigerators, freezers, cold storage, pipeline insu...

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Problems solved by technology

However, in order to reduce the concentration of cyclopentadiene, an inert alcohol solvent is introduced, and the refining and separation process is added. The process is complicated and the loss of solvent is large, which is not conducive to reducing the industrialization cost and the difficulty of process operation. The raw material of ethylene cracking carbon nine-heavy fraction still has sulfur content. high problem

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