Ultrasonic assisted arsenate adsorption on solvothermally synthesized calcite modified by goethite, α-MnO2 and goethite/α-MnO2

• Arsenate sorption is studied on series of novel composite materials.
• Synthesized porous calcite is modified by goethite, α-MnO2 and goethite/α-MnO2.
• Modified synthetic vs. natural calcite shows enhanced sorption properties.
• Higher sorption ability is improved under ultrasound treatment.
• Visual MINTEQ software is used for equilibrium speciation modeling.

A highly porous calcium carbonate (calcite; sorbent 1) was used as a support for modification with α-FeOOH (calcite/goethite; sorbent 2), α-MnO2 (calcite/α-MnO2; sorbent 3) and α-FeOOH/α-MnO2 (calcite/goethite/α-MnO2; sorbent 4) in order to obtain a cheap hybrid materials for simple and effective arsenate removal from aqueous solutions. The adsorption ability of synthesized adsorbents was studied as a function of functionalization methods, pH, contact time, temperature and ultrasonic treatment. Comparison of the adsorptive effectiveness of synthesized adsorbents for arsenate removal, under ultrasound treatment and classical stirring method, has shown better performance of the former one reaching maximum adsorption capacities of 1.73, 21.00, 10.36 and 41.94 mg g−1, for sorbents 1–4, respectively. Visual MINTEQ equilibrium speciation modeling was used for prediction of pH and interfering ion influences on arsenate adsorption.