Biomass-derived Hydrochar and Activated Carbon: Characterization and Water Remediation

This study advocates the use of waste biomass to produce carbon-rich materials, such as activated carbon and hydrochar, aimed at water remediation due to their cost-effectiveness and broad utility. Hydrothermal carbonization transforms waste biomass into slurry-like substances, from which solid hydrochars are derived via filtration. These hydrochars are then further processed into activated carbons through physical activation methods. In our research, we utilized seeds of Tectona grandis, a type of waste biomass, for hydrochar production, which we subsequently converted into activated carbon. We characterized the hydrochar and the activated carbon using various techniques, revealing that the activated carbon possesses a high carbon content and surface area.
In contrast, the hydrochar displays limited porosity yet is enriched with oxygenated functional groups. The thermal stability of the hydrochar, as assessed by means of TGA/DTG analyses, proved to be high. Morphological examination disclosed that the hydrochars comprise structures with spherical elements, which are agglomerated following activation. When tested for the adsorption of 2-bromophenol, the activated carbon exhibited a notable adsorption capacity, reaching nearly 250 mg/g. The Langmuir and the pseudo-second-order models aligned well with the experimental data for isotherms and kinetics. Overall, this investigation underscores the potential of turning waste biomass into valuable materials for water treatment, showcasing a sustainable approach to waste management.