Extraction Equilibrium of Hydrochloric Acid at Low Concentrations between Water and N235 in Isoamyl Alcohol Solution: Experiments and Simulation

Abstract

N235 in isoamyl alcohol solution acts as an efficient extraction system for the revovery of hydrochloric acid (HCl) at very low concentrations in a coupled reactive extraction−crystallization process. In this study, the extraction equilibrium of N235 + isoamyl alcohol + HCl + H 2 O system was investigated systematically. The formation of the extraction complex in the organic phase was determined by using the experimental data and it was confirmed to be (HCl) 4 (R 3 N) 4 (H 2 O) 8 . Further, the thermodynamic model was then established by using Pitzer equation to calculate the activities of all the species. The values of the interaction parameters obtained by regression are as follows: β R 3 N,4:4:8 (org) = 2.8782 and β 4:4:8,4:4:8 (org)= 11.4764. The extraction equilibrium constant is ln K 4:4:8 = 38.0274. The thermodynamic model was demonstrated to be reliable and suitable for the N235 + isoamyl alcohol + HCl + H 2 O system.

Insight into thermal dissociation of tri‐n‐octylamine hydrochloride: The key to realizing CO2 mineralization with waste calcium/magnesium chloride liquids

“…The dataset for each condition is well-correlated to a linear fit, consistent with a first-order process. From Equation (8) we know that the slope equals to −k. All the reaction rate constants are listed in Table 3.…”

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“…Our research group has investigated a novel coupled reactive extraction‐crystallization process systematically to realize the storage of CO 2 with the liquid wastes, such as distiller waste containing plentiful CaCl 2 from ammonia soda process and abandoned MgCl 2 ‐rich brines after the production of potassium fertilizer from salt lake. In the process, CaCl 2 , MgCl 2 were transformed to high‐valued carbonates.…”

Lithium Enrichment of High Mg/Li Ratio Brine by Precipitation of Magnesium via Combined CO2 Mineralization and Solvent Extraction

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Selective Separation of HNO3 and HCl by Extraction: The Investigation on the Noncovalent Interaction between Extractants and Acids by Density Functional Theory

“…Although, the extraction process and interaction mechanism between mineral acids and extractants have been proved by experiments. − However, quantum chemistry calculations can play an important role in addressing the issue of systematically understanding the extraction mechanism from molecular levels. In recent years, there has been an increasing interest in the DFT calculation-assisted design of extractants and the research on the extraction mechanism.…”