Adsorption properties of millimeter porous spheres constructed by montmorillonite nanosheets

It is increasingly urgent to develop low cost and efficient adsorbent due to severe water pollution in the modern society. In this work, montmorillonite (MMT) porous spheres (MPS) were prepared via self-assembly of MMT nano sheets, and their adsorption properties were evaluated by removal of Congo red. Effects of initial solution concentration, solution pH, adsorbent dosage and adsorption time on adsorption properties of the MPS were investigated. The maximum adsorption capacity reaches 598.31 mg·g⁻¹. The adsorption kinetic research indicates the adsorption behavior agrees well with the pseudo-second-order kinetic model, and the adsorption isotherm can be effectively described by the Freundlich isotherm model. The MPS is promising for a wide range of wastewater treatment in industrial applications due to its efficient adsorption performance and recyclability.