Litchi chinensis peel biomass as green adsorbent for cadmium (Cd) ions removal from aqueous solutions

An intensive research of the use of waste biomass for water remediation has led to the exploration of novel founts of these materials. One example is Litchi chinensis peels. This work describes the use of Litchi peels biowaste for the effective removal of Cadmium(II) ions and the influence of environmental variables like pH, sorbent dose, concentration of sorbate and physico-chemical treatments on Cd(II) adsorption capacity. The optimum experimental conditions for the maximum metal uptake were based on pH 5, particle size 43 mu m and a contact time of 60 min. Cd(II) sorption data fitted well to pseudo-second-order kinetic model and Freundlich adsorption isotherms model. According to Freundlich adsorption isotherm the q(max) was found to be 15.27 mg/g. Fourier-transforms infrared spectroscopic analysis of waste biomass exposed the presence of various alkane, alcohol, amines, and oxygen bound groups. The results of this study revealed that Litchi waste biomass is a promising, inexpensive and eco-friendly bio-material that can easily be used for removing high levels of Cd ions from wastewater.