Process for producing hydrogen

The invention relates to a process for producing hydrogen from coke oven gas in which the coke oven gas, if appropriate after scrubbing with benzene under pressure and/or desulphurisation, is subjected to removal of H2 in at least one pressure-swing adsorption unit. In order to improve the yield in hydrogen while maintaining an economical operation, the invention proposes to use the purge gas from a first pressure-swing adsorption unit, into which essentially the entire coke oven gas is introduced, in part for the undergrate firing of the coke oven battery and introducing the other part, if appropriate via a H2 unit consisting of gas purification, cleavage and conversion, into a second pressure-swing adsorption unit in order to separate off H2.