Activated carbon (AC)-metal-organic framework (MOF) composite: Synthesis, characterization and dye removal

Activated carbon (AC), one of the most common adsorbents, and metal-organic framework (MOF), an interesting class of materials, were used for synthesizing AC/MOF composite by the solvothermal method. The strategy designed in this paper is to improve the removal and adsorption performance of AC for dye. MIL-53(Fe) was synthesized on the commercial activated carbon (CAC) to prepare CAC/MIL-53(Fe) composite. Direct Red 23 (DR23) anionic dye was used as a model contaminant. FT-IR, XRD, SEM, and EDX analyses were applied to study the structure and characteristics of CAC/MIL-53(Fe). The parameters (the solution pH, amount of adsorbent dosage, initial dye concentration, and contact time) affecting the dye removal efficiency were investigated. The percentage of dye removal (DR23) under optimal conditions by commercial activated carbon and CAC/MIL-53(Fe) was 50% and 99.9%, respectively. The maximal capacity of adsorption was also raised from 50 to 100mg/g. The adsorption isotherm and kinetics followed the Langmuir and pseudo-second-order models, respectively.