Affinity regulation of the NH₃ + H₂O system by ionic liquids with molecular interaction analysis

Abstract

This work proposed using an adequate ionic liquid (IL) to weaken the affinity between NH and HO as a potential solution to the issue of high-energy consumption involved in separating NH gas from liquid HO. Two quaternary phosphonium-based ILs were selected according to an optimized regulation strategy. The regulation effects of the ILs were evaluated by the vapor-liquid equilibrium property of the NH + HO + IL systems, and were compared with the regulation effects of traditional additives. The results showed that the expected effects were achieved by adding ILs. The regulation mechanisms of different strategies were discussed with respect to the molecular structure and chemical equilibrium for the first time limited to the authors' latest literature review. Finally, the IR spectra of the NH + HO + IL systems were acquired and analyzed to verify the interactions of the ILs with NH and HO.

Solubilities and Thermodynamic Properties of NH3 in Glycerin and its Derivatives

“…24−26 A stainless apparatus was graphically shown in Figure 1. It mainly composed NH 3 cylinder (1), constant temperature water bathe (2,5), NH 3 equilibrium cell (6, EC) with magnetic stirrer to accelerate equilibrium, NH 3 reservoir (3, GR), pressure transmitter (9,13) with digital indicator, and temperature controller (8,11). The volumes of the EC and GR were 48.45 and 118.43 cm 3 as previously determined, respectively.…”

“…As classical absorbents, water and acidic solution are widely used in NH 3 sorption process . However, acidic aqueous solutions suffer from the huge energy consumption during the separation of NH 3 due to large volatility and specific heat capacity of water and high affinity between the absorbent and NH 3 . Large amount of wastewater discharge and equipment corrosion were further limitations.…”

“…4 However, acidic aqueous solutions suffer from the huge energy consumption during the separation of NH 3 due to large volatility and specific heat capacity of water and high affinity between the absorbent and NH 3 . 5 Large amount of wastewater discharge and equipment corrosion were further limitations. Therefore, developing novel and environmental friendly absorbents for NH 3 is believed to be a feasible strategy for solving this problem.…”

Experimental determination and predictive modelling of the mutual diffusion coefficients of water and ionic liquid 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate

“…In addition, the high viscosity of ILs have been identified as the main shortcoming for their applications in absorption systems. Therefore, some authors [13][14][15] have proposed the use of IL as additives in conventional absorbent media, such as water. In this way, instead of the binary system refrigerant + absorbent, the working fluids would be the ternary system refrigerant (such as ammonia) + absorbent (other than ILs, such as water) + ILs (such as [EtOHmim][BF 4 ]) as additives.…”