Using a thermostated reactor and UV/vis spectrophotometer analysis, the solubility of protocatechuic acid (PA) in ethanol, methanol, methyl acetate, and ethyl acetate was measured from (293.15 to 318.15) K at atmospheric pressure. The effect of solvent type and temperature on the solubility are discussed. The relative solubility of protocatechuic acid in different solvents was determined in descending order to be xmethanol greater than xethanol greater than xmethyl greater than xethyl. The experimental solubility data of the solutes (PA) in four pure solvents was correlated with the modified Apelblat equation and semiempirical Buchowski Ksiazczak ?h equation. Dissolution standard molar enthalpy ?solHdeg (kJ*mol 1), Gibbs energy ?solGdeg (kJ*mol 1), and entropy ?solSdeg (J*mol 1*K 1) of protocatechuic acid were estimated using the solubility data:
Compounds
#
Formula
Name
1
C7H6O4
3,4-dihydroxybenzoic acid
2
CH4O
methanol
3
C2H6O
ethanol
4
C3H6O2
methyl ethanoate
5
C4H8O2
ethyl acetate
Datasets
The table above is generated from the ThermoML associated json file (link above).
POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied;
the numbers refer to the table of compounds on the left.