Highly efficient arsenate adsorption removal from wastewater based on activated carbon-iron based metal organic framework in situ grown composites

Abstract

Arsenic is a metal-like pollutant with heavy metal properties, and arsenic and its compounds in industrial wastewater are extremely harmful to humans and their environment. In this study AC@Fe-MOF, a composite based on the in situ growth of MIL-101(Fe) on activated carbon, is prepared using a hydrothermal method. Solved the problems of few active sites and low specific surface area of metal–organic framework (MOF) materials, and improved the adsorbent’s ability to adsorb arsenic in industrial wastewater. The experimental results showed that the maximum arsenic removal rate is 99.59 % at the optimum pH = 9, and the maximum adsorption capacity of arsenic reached 1069.1 mg/g at 10 mg incorporation. By adsorption isotherm and adsorption kinetic surface the adsorption process is consistent with the Freundlich model as well as the pseudo-second-order kinetic model. Characterization before and after adsorption using XRD, thermogravimetry, SEM, FT-IR, BET, and XPS demonstrated the successful synthesis of AC@Fe-MOF, revealing that the reaction of functional groups such as O–H and O-C = C to generate new complexes, the increase of active sites occupied on the surface of activated carbon, and physical adsorption as the main reaction mechanisms. The material shows the feasibility of in situ growth of metal–organic frameworks on activated carbon, which is widely promising in the field of arsenic industrial pollution.