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.

Automated summary

In this study, a composite biochar with enriched surface functional groups was prepared from shrimp shell and rice husk for efficient adsorption of p-nitrophenol. The composite biochar exhibited excellent adsorption performance in a wide pH range, and the pseudo-second-order kinetic model and Langmuir isotherm model were suitable for describing the adsorption behavior. The adsorption mechanisms involved chemisorption, physical adsorption, and pore filling. The tailored surface chemistry and high-efficiency of the composite biochar make it a potential candidate for water body remediation via adsorption process.