Equilibrium and kinetic studies of adsorption of boron on activated alumina.Water Environ Res. 2009 Dec; 81(12):2455-9.WE
Boron is widely distributed in the environment, mainly in the form of boric acid or borate salts, and its contamination of waters is a concern around the world. This study focuses on boron removal by means of adsorption onto activated alumina. Optimum adsorption was achieved in the pH range 8.0 to 8.5. Approximately 60% (by mass) boron removal was achieved using an adsorbent dose of 5 g at an initial boron concentration of 50 mg/L. Adsorption isotherms at 10, 20, and 30 degrees C were investigated. The results fitted with the Langmuir and Freundlich equations showed a monolayer adsorption onto a surface, with a finite number of identical sites. To study the rate-limiting step, the adsorption kinetic data of boron were analyzed using first-order (Lagergren) and second-order kinetic models. The experimental results obtained showed that the adsorption process followed a second-order kinetic model.