Adsorption kinetics, thermodynamics and isotherm of Hg(II) from aqueous solutions using buckwheat hulls from Jiaodong of China

► Feasibility of using buckwheat hulls to produce Hg adsorbent was confirmed. ► Pseudo-second-order kinetic model best described mercury chemisorption behaviours. ► Langmuir model was suitable for mercury adsorption onto BHJC. ► The relevant adsorption thermodynamic parameters were obtained. ► BHJC exhibited 100% selectivity for the meucury in the presence of Zn(II) and Cd(II).