On the modelling of multicomponent acid extraction with long‐chain aliphatic amines

Abstract

The solvent extraction of phosphoric, hydrochloric, sulphuric, hydrofluosilicic and hydrofluoric acids with long‐chain aliphatic amins is modelled. Pure acid equilibria are based on existing isotherms or calculated extraction constants when only experimental data are available. For binary mixtures binary combinations of acid complexes are added. In the aqueous phase Bromley's model for electrolytes is used for calculation of ionic activity coefficients and the appropriate association/dissociation equilibria taken into account for calculation of ionic strength. For the organic phase an empirical model for the non‐ideal behaviour of phosphoric acid is used. For multicomponent mixtures at low acid concentrations the model calculates the extraction of phosphoric, hydrochloric and sulphuric acid almost quantitatively. For hydrofluosilicic and hydrofluoric acid the calculations are less precise and further information is needed about the different fluoride exchange equilibria involved.

Measurement and Correlation of LLE Data for the Ternary System Water+Phosphoric Acid+1-Pentanol at 278.2 K and 288.2 K

“…Pure PA has many applications in food industry, production of phosphate fertilizers, and phosphate fuel cells. Liquid-liquid extraction is a regular method for extracting polar acids including, phosphoric acid, formic acid, and lactic acid from water solution [1][2][3][4][5][6][7][8][9][10][11].…”

Measurement and Modeling of Liquid–Liquid Equilibria for Water–Phosphoric Acid–Aromatic Esters

“…Over the years, numerous equilibrium studies for different ternary or quaternary mixtures of aqueous solutions of PA with organic solvents have been performed by several researchers. − As far as the authors are aware, alcohols, − hydrocarbons, ethers, − esters, ketones, − and aliphatic amines have been tested as nonwater or low-water soluble solvents for the separation of PA from water. Among different types of organic solvents, esters seem to be good extractants for the separation of PA from aqueous solutions.…”

(Liquid+liquid) equilibria in ternary aqueous mixtures of phosphoric acid with organic solvents at T=298.2K

“…Many organic solvents have been tested as extractants for the recovery and purification of phosphoric acid from water. Heavy alcohols, ketones and ethers have mainly been used for extraction of phosphoric acid from aqueous solutions [13][14][15][16][17][18][19][20].…”