Calcium carbonate phase transformations during the carbonation reaction of calcium heavy alkylbenzene sulfonate overbased nanodetergents preparation

► Residual Ca(OH)2 rather than CaCl2 stabilizes amorphous calcium carbonate (ACC). ► ACC transforms into vaterite rather than calcite once carbonation is completed. ► Understanding phase transformation enhances quality control of lubricant additives. ► Overbased nanodetergents in vaterite form of low viscosity obtained for the first time.