Measurement, correlation of the solubility and solution thermodynamics of 2-cyanoguanidine in (methanol + water) binary solvent systems from T = (283.15 to 343.15) K

Abstract

The solubility of 2-cyanoguanidine in binary solvent mixtures (water+methanol) were experimentally measured from T=(283.15 to 343.15)K by the static method. The mass fraction of methanol wt is 0.100, 0.200, 0.300, 0.400, 0.500, and 0.600. The experimental results show that values obtained increased with temperature increasing from (283.15 to 343.15)K. Good agreement was found between the experiments and calculations by the modified Apelblat equation, fifth-order polynomial equation and semi-empirical Buchowski–Ksiazczak λh equation. Our experiment values were proven to give best agreement with the modified Apelblat equation. The dissolution enthalpy ΔdisH (24119.2 to 38593.9J·mol−1), the dissolution entropy ΔdisS (48.4083 to 90.7083J·mol−1·K−1) and the molar Gibbs free energy ΔdisG (7507.9 to 12909.8J·mol−1) were calculated on the basis of the modified Apelblat equation analysis. The solubility and dissolution properties of 2-cyanoguanidine in (water+methanol) binary solvent mixtures obtained in this paper will provide essential support for 2-cyanoguanidine industrial design and further theoretical studies.