Showing papers by "Jayanta Kumar Datta published in 2016"

Fluoride Adsorption by Calcium Carbonate, Activated Alumina and Activated Sugarcane Ash

Abstract: The aim of this research work is to develop a novel cost effective strategy for fluoride removal, applicable to rural areas of developing countries. Most of the adsorbent based technologies for fluoride removal work at acidic pH which is not a feasible condition for application in rural areas. This study investigates the feasibility of three low-cost adsorbents (calcium carbonate, activated alumina, and activated sugarcane ash) for the removal of fluoride ions by adsorption using a synthetic fluoride solution (3.0–30.0 ppm). The effects of various process parameters have been investigated by the following batch adsorption technique at 30 ± 1 °C. Fluoride ion adsorption increased with increasing adsorbent dose for all the adsorbents. Adsorption of fluoride increased with increasing contact time and reached equilibrium at 100 min. Adsorption data were fitted with the Langmuir isotherms. The maximum fluoride adsorptions occurred as 12.5 mg/g, 1.2 mg/g, 10.99 mg/g for calcium carbonate, activated alumina and activated sugarcane ash, respectively. Further, fluoride adsorption of all the studied adsorbents follows pseudo-second-order kinetics (R2 0.99). Intra-particle diffusion model revealed that activated carbon of sugarcane ash is more effective in adsorption of fluoride. Thermodynamic study showed spontaneous nature and feasibility of the adsorption process with negative enthalpy (∆H0) value also supported the exothermic nature. These results indicate that activated carbon of sugarcane ash can be used as an effective, low-cost adsorbent to remove fluoride compared to calcium carbonate and activated alumina.