Removal of rhodamine B from aqueous solutions by tea waste

Adsorption removal of a cationic dye, rhodamine B (RhB) from water onto the tea waste (TW) was investigated. The effects of several variables on the removal of RhB were studied, including initial RhB concentration, pH and contact time. Attempts were made to fit the isothermal data using Langmuir and Freundlich equations. The experimental results have demonstrated that the equilibrium data are fitted well by a Freundlich isotherm equation. Pseudo-first-order and pseudo-second-order models were considered to evaluate the rate parameters. The experimental data were found to follow the pseudo-second-order kinetic model. FTIR analysis was also carried out to examine the possible interaction between adsorbent and RhB. The results indicate that the tea waste could be used as a low-cost absorbent for the removal of cationic dyes from aqueous solutions.