Magnetic Biomass Activated Carbon Derived from Wood Tar Waste for Effective Methylene Blue Adsorption

Wood tar is the main by-product of thermal cracking of biomass. Magnetic biomass activated carbon can be prepared from wood tar. The phenol component in the wood tar is volatile, which result in the loss of organic carbon. In this study, volatile component in wood tar was firstly fixed by phenolic reaction. The resinifero wood tar was subsequently employed to prepare magnetic biomass activated carbon through carbonization, activation and magnetization steps. The surface structure, property and magnetic properties of magnetic biomass activated carbon analyzed by a variety of techniques. Rich oxygen group and high specific surface area of the as-prepared M-RWTAC can provides convenient condition to the adsorption contaminate. Adsorption behavior of the as-prepared M-RWTAC was evaluated with MB as a model of dye pollutant. The MB adsorption of M-RWTAC is in accordance with the pseudo-second-order kinetic model and Langmuir model is predominant for this adsorption system with the maximum adsorption capacity of 528 mg/g. The adsorption of MB onto M-RWTAC is an exothermic and entropy production process. The regenerated M-RWTAC can be recycled with the removal efficiency of 82.5% after 5 successive adsorption cycles. The present study provides a new route to utilize wood tar by-product of biomass pyrolysis.