Unseeded Supersolubility of Lithium Carbonate: Experimental Measurement and Simulation with Mathematical Models

A laser aparatus was employed to investigate the unseeded supersolubility values of Li2CO3 in aqueous solution. It shows the supersolubility of Li2CO3 decreases with the raise of temperature and stirring speed, and with a reduction of feeding rate of Na2CO3. The introduce of ultrasound field leads to obvious reduction on supersolubility, whereas magnetic field causes little effect. The involving factors of impurities and additives on the supersolubility were also studied. It is found that the supersolubility value decreases with the addition of NaCl, KCl, NaNO3 and NaBr, while increases at the presence of Na2SO4, CH4N2O, NH4Cl, (NH4)2SO4 and EDTA disodium. Meanwhile, two mathematical models, empirical correlation and BP neural network, were used to simulate the supersolubility value as a function of temperature and feeding rate of Na2CO3. Compared with empirical correlation method, BP neural network simulation has better consistence with the experimental data.