Manganese-modified lignin biochar as adsorbent for removal of methylene blue

Methylene blue, a prevalent cationic type dye, has been extensively utilized in textile industry. Lignin generates as a byproduct and its utilization is required to add a potential economic benefit of a biorefinery process. Lignin-derived porous biochar, as a promising adsorbent, was propitiously prepared by chemical modification with different oxidation number manganese compounds (KMnO4, MnSO4, and MnO2). The adsorption capacity of MnO2-loaded biochar to methylene blue dye was substantially higher relative to original biochar. The maximum adsorption capacity was 248.96 mg/g and removal rate was 99.73%, as compared to 234.65 mg/g and 94.0% for unmodified biochar. In comparison, the decolorization rate of the modified biochar exceeded 95%. Substantial results showed that methylene blue has a strong binding affinity with MnO2 modified biochar. Adsorption kinetics was described by a quasi-second order model and methylene blue adsorption isotherm was better fitted by Langmuir model. The research provides a promising way for the removal of methylene blue from wastewater through the manufacture of adsorbent from byproduct of biorefinery process. (C) 2021 The Author(s). Published by Elsevier B.V.

Automated summary

The study successfully prepared an adsorbent from lignin-derived biochar modified with MnO2, which showed significantly enhanced adsorption capacity for methylene blue dye. The modified biochar exhibited higher efficiency and decolorization rate in removing methylene blue, demonstrating potential application in reducing environmental pollution.