Kinetics investigation on the decomposition process of supersaturated sodium aluminate solution using UV spectroscopy

Abstract

The kinetics of the spontaneous decomposition process of supersaturated sodium aluminate solution was investigated by UV spectroscopy. The UV spectra show that the absorbance increased with time at the initial decomposition stage. At 369nm, the concentration of the intermediate reached the maximum after decomposition for 9h. The spontaneous decomposition process from sodium aluminate solution was considered as the consecutive complicated reaction and the kinetic model was established. The rate constants of the two elementary reactions were calculated as k1=0.02447h−1 and k2=0.3046h−1 respectively. The concentration of Al-containing species with time was also predicted in the decomposition process of supersaturated sodium aluminate solution.