Ammonia synthesis gas from hydrocarbon(s) - by converting carbon mon:oxide in crude prod. into di:oxide, removing di:oxide, and removing residual impurities by adsorption

摘要

A process is claimed for the prodn. of ammonia gas (I) by converting hydrocarbons (II) into a crude H2/CO synthesis gas which is then conditioned further by subjecting it to a CO-shift, removing CO2 and eliminating residual impurities in a purification stage; the novelty is that residual CO and CO2 are removed by absorption on suitable adsorbents (III). Residual impurities are removed by temp. cycling adsorption, CO is removed with a CO selective adsorbent, and CO2 with a CO2 selective adsorbent; exhausted adsorbent is regenerated by flushing with ammonia synthesis purge gas. ADVANTAGE - The process enables the purification of the crude synthesis gas with reduced loss of hydrogen, w.r.t. prior-art processes.