Resumen
Empty fruit bunch (EFB) was utilized into biochar by pyrolysis and used as adsorbent for malachite green (MG) dye removal. EFB biochar were produced at temperature 300°C, 400°C, 450 °C and 500°C. Characteristics of biochar were characterized by moisture content analysis, ash content analysis, Fourier Transform Infrared (FTIR) Spectroscopy and pH zero point change analysis. As the pyrolysis temperature increases, the moisture content of EFB decreases while the ash content of EFB biochar increases. The FTIR spectra of EFB biochar showed the organic part of EFB was mainly compound of lignin, cellulose and hemicellulose with different functional groups such as amides, alcohols, phenols, carboxylic acids, ethers and esters for MG dye adsorption. pH 7.0 is the pH value obtained for pH zero point charge analysis. The optimum adsorbent dosage is 0.05 g and the adsorption process reach equilibrium within 120 minutes with maximum value, 14.7142 mg/g for adsorption capacity of MG dye. For adsorption kinetic, pseudo-second-order model is more preferable than pseudo-first-order model indicating chemical adsorption which involved valence forces by exchange or sharing of electrons between the EFB biochar and MG dye. While for adsorption isotherm, Langmuir isotherm is more preferable than Freundlich isotherm indicating a monolayer adsorption and the whole adsorption sites are homogeneous at the EFB biochar.