a process for the separation of carbon dioxide and other acid gas components , in a compound distillation column , from a gaseous mixture comprised of one or more hydrocarbons , inclusive of methane , and hydrogen . the compound distillation column is sectioned , one section of which is operated at higher pressure than another , and hence in a relative sense is referred to as a high pressure section while the other is referred to as a low pressure section . a product , principally methane , is removed from the high pressure section while a product of principally acid gases is removed from the low pressure section . by maintaining the sections at different pressure , the separations are more efficiently made and phase separation of products in the low pressure section is easily maintained .