Solubility Measurement and Data Correlation of 4-Chlorophenoxyacetic Acid in 13 Monosolvents at Temperatures from 283.15 to 328.15 K

Abstract

The solubility of 4-chlorophenoxyacetic acid (4-CPA) in 13 monosolvents including ethanol, 1-propanol, isopropanol, 1-butanol, 2-butanol, isobutanol, ethyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, acetonitrile, and 1,4-dioxane was measured by a gravimetric method from 283.15 to 328.15 K at an atmospheric pressure of 0.1013 MPa. The solubility of 4-CPA increased with temperature and followed the order 1,4-dioxane > alcohols > esters > acetonitrile at all experimental temperatures. The solvent effects, especially solvent polarity, hydrogen bond donor propensity, and hydrogen bond acceptor propensity, were used to analyze the solubility of 4-CPA in different solvents. The solubility basically follows the rule “like dissolves like” and has a higher value in solvents with strong hydrogen bond donor propensity and hydrogen bond acceptor propensity. Besides, the modified Apelblat equation, λh equation, and van’t Hoff equation were applied to correlate the measured solubility data. The average relative deviation (ARD) values showed that the correlation results of the three models agree well with the experimental data.