Kinetic Modeling of the Alkaline Decomposition and Cyanidation of Argentojarosite

the jarosite sample used is an argentojarosite-hydroniumjarosite solid solution of approximate formula (ag0.78h3o0.22) fe3(so4)2 (oh)6. the decomposition process in naoh/ca(oh)2 media and the cyanidation process in ca(oh)2 media were studied for the induction period and progressive conversion period respectively, and the reaction order and activation energy were determined for each case. the results are consistent with the spherical particle shrinking core model and chemical control under the experimental conditions imposed; six partial models and three global models have been tested for both processes in their basic behaviour.