Adsorption of Cu2+, Pb2+, and Cd2+ onto oiltea shell from water. (January 2019) - Liu, Jiayang
Highlights: Oiltea shell was used to adsorb Cu 2+, Pb 2+, and Cd 2+ . Isotherm, kinetic, and thermodynamic were fitted. Column adsorption was performed with single and tertiary solution. Maximum adsorption capacity was obtained in batch and column study. Adsorption of dye and metal ions was performed in their mixtures. Abstract: Agro-processing waste oiltea shell (OTS) has been previously proven effective in removing dye from water by adsorption. This study further evaluated its capability to adsorb heavy metals in aqueous solution. Adsorbent dosage, pH, ion concentration, temperature, and contact time were investigated in batch experiments. Pseudo-second order kinetic better described the adsorption process for the three ions. Langmuir equation was more suitable for Cu 2+ and Cd 2+, while Freundlich for Pb 2+ . The maximum adsorption capacity was 22.4 (Pb 2+ ), 12.1 (Cu 2+ ), and 14.2 mg/g (Cd 2+ ), respectively. The adsorption was spontaneous and endothermic. Adsorption was then performed in column and Thomas model was fitted, based on which the maximum adsorption capacity was 7.42 (Cu 2+ ), 4.17 (Pb 2+ ), and 18.02 mg/g (Cd 2+ ), respectively. High removal rate of metal ions and dye methylene blue was also achieved from their mixture solution. OTS is therefore a promising biosorbent in treating wastewater with organic and inorganic pollutants.