Optimization of sylvite transformation into arcanite using experimental design methodology

This study is an application of the experimental design methodology for optimizing a potassium sulfate synthesis reaction. The latter is a two‐stage reaction through an intermediate product (Schoenite: K 2 SO 4 .MgSO 4 ·6H 2 O). To determine optimal experimental conditions of the first stage, we have conducted a fractional factorial design and a central composite one. The optimal conditions of the second stage were determined only by means of a fractional factorial design. Several physico‐chemical techniques were used to implement this study, namely potentiometry, complexometry, gravimetry and X‐ray diffraction. This work has showed that this double decomposition reaction, when performed under the determined optimal conditions, gives good quality potassium sulfate (purity more than 95%) with a maximal yield.