Sorptive removal of copper(II) from water by biochar produced from a novel sustainable feedstock: wild herbs.

We have reported the removal performance from the synthetic aqueous solution of copper of a low-cost and eco-friendly biochar (WHC) produced by facile thermal pyrolysis of wild herbs (WH), a new feedstock, at 550 °C under anoxic conditions. The characteristics of WHC were determined by physicochemical techniques. It exhibited a low BET surface area, total pore volume, and mean pore size of 16.45 m2/g, 0.01 cm3/g, and, 2.34 nm respectively. Batch sorption studies were performed by examining the effects of varying pH, WHC dosage, initial Cu(II) concentrations, interaction time, and temperature to determine optimum removal conditions. In modeling of sorption, data were used the pseudo-first- and pseudo-second-order kinetics and the Langmuir and Freundlich isotherm models. The maximum Cu(II) sorption capacity of WHC was 24.21 mg/g. Thermodynamic parameters were computed for predicting the nature of WHC-Cu(II) sorption system.