Quaternary carboxylate compositions for extracting C₁to C₄carboxylic acids from aqueous streams

摘要

This invention relates to solvents for extracting C1 to C4 carboxylic acids from aqueous streams. More specifically, the extraction solvents include one or more salts composed of a tetraalkylphosphonium cation and a carboxylate anion. The extraction solvents may further include one or more non-ionic liquid organic solvents as an enhancer. The extraction solvents are useful for extracting aqueous mixtures containing one or more lower carboxylic acids, such as monocarboxylic acids, alkoxycarboxylic acids, and halogen-containing carboxylic acids.

主权项

1. A composition for separating a C1 to C4 carboxylic acid from water, the composition comprising:
(a) a quaternary phosphonium carboxylate salt; (b) a hydrophobic non-ionic organic solvent; (c) a C1 to C4 carboxylic acid; and (d) water, wherein the hydrophobic non-ionic organic solvent is not the extract, and wherein the carboxylate salt has the general formula 1: wherein
R1, R2, R3 and R4 are each independently a C1 to C26 hydrocarbyl group, provided that R1, R2, R3, and R4 collectively have a total of at least 24 carbon atoms; andR5 is hydrogen or a C1 to C24 non-aromatic hydrocarbyl group.