Preparation,Characterization and Adsorption Performance for Malachite Green of Modified Distiller's Grain Biochar
Biochar was obtained through the pyrolysis of distiller's grains in a nitrogen(N2)atmosphere,which was further modified with potassium permanganate(KMnO4)for the adsorption of malachite green in dye wastewater.The morphology and functional groups of the biochar were characterized using Scanning Electron Microscopy(SEM),X-ray Diffraction(XRD),and Fourier Transform Infrared Spectroscopy(FTIR).The effects of solution pH,adsorption time,and temperature on the adsorption performance of the biochar were also investigated.The results indicated that the modification with KMnO4 significantly increased the number of oxy-gen-containing functional groups on the biochar surface and reduced its Zeta potential,thereby effectively en-hancing the adsorption capacity for malachite green.Moreover,the adsorption process of the modified biochar for malachite green was consistent with the Langmuir adsorption isotherm model and the pseudo-second-order kinetic model,suggesting that the adsorption process was primarily controlled by a chemical adsorption mecha-nism.An increase in temperature was found to be beneficial for the adsorption process,with the equilibrium ad-sorption capacity reaching 82.21 mg/g at 303 K.It is evident that the rational modification of biochar to en-hance its adsorption performance can provide a new approach and method for the efficient treatment of dye wastewater.