Fig. 5
From: A study on the dissolution rates of K-Cr(VI)-jarosites: kinetic analysis and implications
SEM image of partially decomposed particles in H3O+ medium (0.01 mol L−1, T = 50 °C, pH 2.01, d0 = 38–44 µm, CrO −24 = 0.77 mol); a tr = 500 min; b tr = 1000 min; c tr = 1500 min; d tr = 2000 min. Results show that the unreacted core kinetic model without formation of an ash layer describes the dissolution process of KFe3[(SO4)2 − X(CrO4)X](OH)6 in H3O+ medium