Dual-wastes derived biochar with tailored surface features for highly efficient p-nitrophenol adsorption

In line with the concept of green sustainable development and efficient wastewater remediation, it is urgent to fabricate biochar-based sorbents with high-efficiency for pollutant removal. Herein, mixed bio-waste of shrimp shell and rice husk was simultaneously employed to prepare composite biochar with enriched surface functional groups for p-nitrophenol adsorption. Batch experiments were conducted to study the adsorption performance under different conditions, by which excellent adsorption capacity in a wide pH range (3–10) was revealed. The pseudo-second-order kinetic model was suitable for p-nitrophenol sorption kinetic, and the maximum sorption capacity of 636.42 mg/g based on the Langmuir isotherm model could be achieved. The main adsorption mechanisms of p-nitrophenol on biochar were the adsorption (chemisorption and physical adsorption) and pore-filling. By virtue of tailored surface chemistry features and high-efficiency, the composite biochar prepared from shrimp shell and rice husk might be a potential candidate for water body remediation via adsorption process.