Kinetics, Thermodynamics, and Isotherm Properties of Lead & Silver Metal Ions Removal from Aqueous Solution Using Tea Leaves and Tea Fibers (Camellia sinensis)

The growing human population and industrial demands increase heavy metal contamination, posing health risks. This research explores sustainable methods for removing heavy metal using Camellia sinensis, commonly known as tea leaves and tea fibers, examining adsorption capacity and effects of temperature, chemical dosage, time, and initial metal concentrations. Adsorption isotherms were employed to analyze the research data to show the thermodynamics and kinetics studies of the sorption process. FTIR spectroscopy confirmed active functional groups like C-O, N-H, and C-N in the Tea leaves and fibers. The Langmuir adsorption isotherm shows the correlation coefficient (R2) of 0.3791 and 0.0092 for investigating the biosorption of silver and 0.0379 and 0.1708 for the biosorption of lead by tea leaves and tea fibers respectively. On silver, the Freundlich isotherm shows R2 values for tea leaves and tea fibers as 0.5218 and 0.1392, respectively, and on lead, it yields R2 values of 0.0308 and 0.1771, respectively. The kinetic results utilized first and second-order kinetics, with the second-order fitting well for experimental results of the sorption process of tea leaves and tea fibers sanctum on silver and lead. Thermodynamic studies suggest a spontaneous, endothermic, and practical adsorption process. This study indicated that Tea leaves is a more appropriate cost-effective Lead Pb(II) and Silver (Ag) removal of industrial effluent and wastewater.