Synthesis of pure aragonite by sonochemical mineral carbonation

► Ultrasound combined with Mg2+ enhances the synthesis of aragonite by carbonation. ► High purity (>98%) aragonite precipitated at 24 °C with optimized process conditions. ► Influence of several process parameters on product purity explored for optimization. ► Novel aragonite crystal morphology (hubbard squash-like) produced at low temperature. ► Fed-batch process tested as scale-up route for production of pure aragonite powder.