Rubidate

Due to the poor water solubility of rubidate, it is difficult to prepare and apply.In this work, the objective is to study the dissolution behavior of rubidate in (methanol + water) and (ethanol + water) mixtures and calculate apparent thermodn. properties.In selected two mixtures, it increased monotonically with the increasing mass fraction of alcs. at all researched temperaturesWhen the mass fraction of alc. is more than w = 0.5, the solubility increases sharply, and the largest mole solubility data was found in pure alcs. (3.344 x 10^-2 in methanol at 318.15 K, and 5.506 x 10^-2 in ethanol), the min. data was in pure water (0.581 x 10^-6 at 318.15 K), an increase of 5.76 x 10⁴ folds in methanol aqueous, and 9.48 x 10⁴ folds in ethanol aqueousThe commonly used thermodn. models (Jouyban-Acree model and CNIBS/R-K model) were used to correlate the exptl. results.Because the relative average deviation (RAD) of two models was more than 5%, the calculated value by two models was further evaluated with residual value anal.In the following, the anal. of apparent thermodn. properties indicated that the dissolution process is apparently not only endothermic but also entropy-driving.The study on the dissolution behavior of rubidate in alc. aqueous is helpful to optimize the preparation and purification process.