Carbon-containing molecular sieves
Recovery of hydrogen and ammonia from purge gas
Pressure swing adsorption recovery
Adsorptive separation of gases
ApplicationNo. 07/045347 filed on 05/04/1987
US Classes:62/624, Membrane62/908, Filter or absorber95/128, Nitrogen containing compound sorbed95/130, Nitrogen sorbed95/143Hydrocarbon sorbed
ExaminersPrimary: Warner, Steven E.
Attorney, Agent or Firm
International ClassesC01C 1/04 (20060101)
C01C 1/00 (20060101)
C01B 23/00 (20060101)
F25J 3/02 (20060101)
B01D 53/04 (20060101)
AbstractAn improved high yield process is disclosed for argon recovery from an ammonia synthesis plant purge gas comprising hydrogen, nitrogen, argon, ammonia, and methane. In one embodiment of the present invention, this purge gas is subjected to the following steps:(i) Separation of ammonia at high pressure by adsorption using zeolite molecular sieve material, which is subsequently regenerated by hot purge combined with pressure reduction;(ii) Separation of methane and most of the nitrogen by pressure swing adsorption using a molecular sieve or an activated carbon material having greater selectivity for methane than argon;(iii) Separation of hydrogen for recycle to the ammonia synthesis plant using a high pressure cryogenic distillation column or a membrane separator; and(iv) Separation of the nitrogen by cryogenic distillation means to obtain essentially pure liquid argon product.