Catalytic syntheses with high yields - suitable for mfg. ammonia, methane, methanol, or the conversion of carbon monoxide

摘要

A reversible, exothermic, gas-phase reaction is undertaken where a gas stream contg. one or more reactants is fed through =1 catalyst zones to obtain =1 prods. The gas stream is fed at temp. (T1) into a first reaction zone (R1) using adiabatic conditions so as higher temp. (T2) is attained; T2 is lower than the inactivation temp. of the catalyst. The gas at T2 then flows into a second zone (R2) provided with continuous external cooling to obtain a prod. mixt. leaving zone (R2) at temp. (T3) which is lower than T2. The gas may be recycled through the process and T3 is pref. max. T1. The initial gas is pref. a mixt. of (a) N2 and H2 for mfg. NH3; or (b) H2 and CO for mfg. methanol; or (c) COx and H2 for mfg. methane; or (d) H2 and CO, and using a CO conversion catalyst. Improved yields in the synthesis of cpds. such as CH3 OH or NH3 are obtd. For example, the % of NH3 in the outlet gas can be raised to 20% c.f. 16.5-17.5% obtd. in conventional processes.