A novel activated carbon from human hair waste: Synthesis, characterization and utilization thereof as an efficient, reusable Ni (II) adsorbent

Abstract In this study, the novel hair based activated carbon (HAC) was synthesized from human scalp hair using calcium chloride as an activating agent and characterized using FTIR, Raman, CHNS, BET, SEM, and XRD analysis methods. The Ni (II) adsorption investigations were performed in batch mode experiments by determination of its initial and momentary concentrations in the solution. The effect of pH, adsorbent dose, Ni (II) initial concentration, and adsorption time on HAC adsorptivity, were evaluated using Taguchi experimental design method. Kinetics, isotherms, and regeneration studies were also performed. The optimum values of the four parameters, mentioned above, were found as 5, 1 ​g/L, 27.70 ​mg/L, and 60 ​min, respectively. The Ni (II) adsorption kinetic and isotherm were best described by pseudo-second order and BET models, respectively. After five adsorption-desorption cycles, a very small decrease (6.85%) in adsorbent capacity was observed. According to the BET isotherm model, the maximum multilayer adsorptivity was 63.44 ​mg/g. Due to the simple preparation, ease to scale-up, high adsorptivity, as well as regeneration results, the obtained bio-based activated carbon can be introduced as a strong, stable, and reusable adsorbent of Ni (II).