Development and application of sewage sludge biochar for the removal of methyl red from water environment.

Currently, development of an efficient natural adsorbent to remove pollutions becomes crucial since adsorbents derived from chemicals have several shortcomings such as their potential as a new pollution in the environment. Therefore, this study aims to investigate the capability of sewage sludge biochar for the removal of dye. Sewage sludge biochar was synthesized by pyrolysis at different temperatures, which were 350°C, 450°C, 550°C, 650°C, 750°C, and 850°C. The characterization of biochar was conducted by analyzing the percentage yield, ash content, moisture content, Fourier-transform infrared spectroscopy, and pH zero charge. This study found that as the pyrolysis temperature increased, the percentage yield along with moisture content decreased meanwhile the ash content increased. For kinetic studies, pseudo-second-order model gave better result than pseudo-first-order model indicating that adsorption mainly takes place on chemical adsorption. The applicability of adsorption isotherm analyses indicates that the adsorption mechanism followed Freundlich isotherm compared to Langmuir as Freundlich give value of R2 nearer to 1 (0.9962). It showed that adsorption mechanism behaves in a multi-molecular layer and the adsorption sites are heterogenous on the sewage sludge biochar. [ABSTRACT FROM AUTHOR]