Highly efficient simultaneous adsorption and biodegradation of a highly-concentrated anionic dye by a high-surface-area carbon-based biocomposite

•Agricultural waste as an eco-friendly strategy for dye removal from wastewater.•Simultaneous chemical-physical activation technique promoted surface area.•MHSA-AC could adsorb AO10 effectively to protect bacteria from harm.•High-concentrated AO10 could be removed completely by SAB process.

Mesoporous high-surface-area activated carbon (MHSA-AC), which has a honeycomb structure, was produced from coconut shells by simultaneous chemical and physical activation and used for the rapid adsorption of an anionic dye, namely acid orange 10 (AO10), from water. Owing to its porosity and high Brunauer-Emmett-Teller surface area (2283.91 m2g−1), MHSA-AC is a highly efficient adsorbent. It also has good biocompatibility and is a good immobilization carrier; the grooves on the MHSA-AC surface facilitate immobilization. Here, a new, highly efficient, and environmentally friendly simultaneous adsorption and biodegradation (SAB) process was developed. Highly concentrated AO10 (6000 mg L-1, 20 mL) was removed with an efficiency of 100% (pH = 7, 35 °C) by SAB using cells immobilized on MHSA-AC (500 mg). The immobilized cells were used directly, without pretreatment; the SAB process is therefore simple and has good potential for application in the treatment of dyes in industrial wastewater.

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