Synthesis, Characterization and Adsorption Properties of Low-cost Porous Calcined Dolomite Microspheres for Removal of Dyes

Low-cost porous calcined dolomite microspheres were prepared by simple spray drying and subsequent calcination. Effects of calcination temperature on phase evolution and adsorption properties of MB were investigated systematically. Results showed that microspheres treated at 400 °C kept mainly calcium carbonate (CaMg (CO3)) phase with some small pores, showing better removal efficiency for MB. With the dosage of 20 g/L under the starting concentration of 100 mg/L, the removal efficiency of the microspheres reached 95.6%. The adsorption kinetics data followed the pseudo-second-order kinetic model, and the isotherm data fit the Langmuir isotherm model. The low-cost microsphere could be applied as a promising absorbent for dyes in wastewater filtration and adsorption treatment.