Supporting Data for Cyanide removal from gold tailings wastewater by FeCl3-modified sorghum stalk biochar: Adsorption optimization and model selection

The dataset includes: Fourier Transform Infrared (FTIR) spectroscopy data for unmodified sorghum stalk biochar (SSB), FeCl₃-modified sorghum stalk biochar (FSSB), and cyanide-loaded FSSB (FSSB-CN); X-ray Diffraction (XRD) patterns for SSB, FSSB, and FSSB-CN; Point of zero charge (pHₚzc) experimental data used to determine the surface charge characteristics of FSSB; Adsorption equilibrium isotherm data, including equilibrium cyanide concentrations and adsorption capacities used for nonlinear isotherm modelling; Adsorption kinetics data comprising cyanide concentrations and adsorption capacities measured at different contact times for kinetic model fitting.

The data were generated to characterize the physicochemical properties of the adsorbent and to evaluate the adsorption mechanism, equilibrium behaviour, and kinetics of cyanide removal from gold tailings wastewater. All data are provided in their original format to facilitate reproducibility, independent validation, and reuse in adsorption modelling and comparative studies involving iron-modified biochars for cyanide remediation.