Kinetic investigation of reaction between metallic silver and nitric acid solutions

In this study, the reaction kinetics between metallic silver and nitric aci d solutions was investigated by taking into consideration the parameters of temperature, solid-to-liquid ratio, stirring speed, nitric acid concentrat ion, particle size and addition of sodium nitrite. It was determined that t he dissolution rate of the process increased with decreasing particle size and solid-to-liquid ratio, and increasing nitric acid concentration, reacti on temperature and the amount of the sodium nitrite in the solution. In add ition, it was observed that the stirring speed had more effect on the disso lution rate at low stirring speeds than at high stirring speeds. In the pre sent study, the examination of shrinking core models of fluid-solid systems showed that the dissolution of metallic silver in the nitric acid solution s was controlled by the reaction on the surface. A semiempirical model, whi ch represented well the process, was developed by statistical methods. The activation energy of the process was found to be 57.66 kJ mol(-1).