Adsorption Research of Tetracycline from Water by HCl-Modified Zeolite

Abstract

The sorption performance of tetracycline (TC) on HCl-modified zeolite under different conditions was investigated. HCl-modified zeolite exhibited more than two times higher adsorption capacity than natural one. Adsorption kinetics and adsorption equilibrium isotherms were studied by conducting series of batch experiments. The kinetic analysis indicated that the pseudo-second-order kinetic model was well described the sorption equilibrium process of tetracycline onto natural and HCl-modified zeolites, and intra-particle diffusion was not the only rate-limiting in the sorption process. The results from sorption equilibrium studies showed that the Langmuir and Dubinin-Radushkevich (D-R) isotherm models were well fitted to experimental data, the value of E confirmed that the adsorption was controlled by physical combined with chemical adsorption mechanism. The sorption removal capacity is relatively higher at low pH. The adsorption removal rate of wastewater containing 0.1 mmol/L tetracycline was 95.5% when the dosage of treated zeolite was 0.05g.