Preparation and dye removal performance of MnFe₂O₄@diatomite composite

Abstract

Massive discharge of dyes by industries into environment has posed a threat to aquatic organisms and human health.In order to reduce dye pollution, a MnFe2O4@diatomite composite adsorbent(MnFe2O4@DE) with excellent removal effect of malachite green(MG) in wastewater and simple preparation method was prepared in this study.A variety of characterization methods were used to analyze structural properties of the composite and its adsorption effect on MG was also systematically studied.The results showed that the MnFe2O4 nanoparticles were well distributed on the surface of diatomite.Compared to two monomer materials, the specific surface area(112.1 m2/g) and pore volume(0.24 cm3/g) of the composite increased significantly.The as-synthesized composite exhibited enhanced adsorption behavior to MG, and its maximum adsorption capacity could reach 25.70 mg/g, which was up to around 1.89 and 1.13 times as much as that of diatomite(DE) and MnFe2O4 respectively.The adsorption process was spontaneous and endothermic, which was consistent with pseudo-second-order kinetic model and Langmuir model.And MnFe2O4@DE also showed good reusability.After 4 times of reuse, composite still had 87.56% removal effect on MG.Therefore, MnFe2O4@DE has good application potential in dye pollution control.

Keywords

• diatomite
• nano iron-manganese oxide
• composites
• adsorption
• dye