Study of Partial Pressures of NH sub 3 , CO sub 2 , and H sub 2 O over Aqueous Solutions of Ammonium Carbamate at 140 to 200 exp 0 C (Report 3)

摘要

Based on the data produced on the study of partial pressures of NH sub 3 , CO sub 2 and H sub 2 O over aqueous solutions of ammonium carbamate at high temperatures, the following conclusions can be drawn: (1) For solutions with NH sub 3 :CO sub 2 ratios of 2:1, as the temperature rises to 200 exp 0 C, a sharp increase is noted in the CO sub 2 vapor pressure with a slight increase in the NH sub 3 vapor pressure. (2) An increase in the solution concentration from 50 to 200 g/l NH sub 3 also leads to a significant increase in the partial pressure of CO sub 2 , but has little influence on the NH sub 3 vapor pressure. (3) The addition of NH sub 4 NO sub 3 to solutions of ammonium carbamate greatly increases the CO sub 2 vapor pressure, although an increase in the NH sub 3 vapor pressure is observed as well, leading to a decrease in the CO sub 2 :NH sub 3 ratio in the gas. (4) The distillation of aqueous solutions of ammonium-carbon salts at NH sub 3 :CO sub 2 = 2:1 and at temperatures of 160 to 200 exp 0 C can be used to separate from the solutions up to 80 percent of the CO sub 2 in compressed form at up to 60 to 70 atm. (ERA citation 03:001211)