Jarosite dissolution kinetics in the presence of acidic thiourea and oxalate media

This work explores the effect of temperature and pH on the decomposition and leaching of a heterogeneous particle size (d(80) = 24 mu m) industrial jarosite composed mainly of natrojarosite in an acid medium. The kinetic study of the decomposition process and of the leaching reaction was determined by fitting the data to the multiparticulate shrinking core model. The results of the adjustment indicated that the controlling phenomenon was the heterogeneous decomposition reaction, which was consistent with the activation energy (43-44 KJ mol(-1)) for pH values between 1 and 2, indicating that the silver dissolution reaction is the controlling factor in this system.