Superior removal performance for methylene blue onto Spartina alterniflora biochar via solvothermal method: Equilibrium, kinetics and mechanism analyses

In this study, an activated biochar derived from Spartina alterniflora (SRHH) was innovatively synthesized to efficiently remove dye contaminants from aqueous solution. A series of characterizations exhibited that solvothermal process effectively increased the mesopores and functional group structure (OH, NHR, CO, CO and RNCO) of the nanomaterial, which could also acquire amorphous carbon-doped biochar with less energy consumption. Moreover, the results showed that the as-prepared sample in a solvothermal kettle at 180 °C displayed superior dye adsorption and degradation performance, and the removal efficiency entirely could reach up to 93% within 4 h at neutral condition. The adsorption process was both consistent well with the pseudo-second-order and intraparticle diffusion models, indicating that diffusion resistance within the particle pore size and chemical action might be predominantly controlled factor. Therefore, the prepared catalyst has enormous potential in the removal of organic pollution as a low-cost and economical in-situ remediation material.