Combined process for prodn. of hydrogenation gas and cyclohexane - by reforming recycled gas with fresh hydrocarbon

摘要

First stage comprises converting with steam a mixt. of =1 hydrocarbon with recycled gas (as below) to form a hydrogenation gas contg. a major proportion of hydrogen and a minor proportion of methane. In a second stage, the hydrogenation gas is reacted with benzene to produce cyclohexene and a gas is sepd. of which at least part is returned to the first stage as recycled gas. Process enables re-use of gas even when the H2 content is 60-70%. Less hydrocarbon is required and a cheaper less active catalyst may be used in the 1st stage. In operation less coke formation occurs, there is improved heat transfer and simpler plant is required.