Treated and Regenerated Deactivated Alumina Solid Waste for Fluoride Removal from Ground Water as an Adsorbent.

Abstract

Fluorine is among the prioritized contaminant of water that causes for fata problem if taken above recommended levels. Hence, the design and development of effective management is very crucial. One of the removal techniques of fluoride is implementing a cost effective, locally accessible, not time consuming and at the same time, environmentally friendly technology has been widely studied by many scholars. The objective of this study was to use treated deactivated Alumina solid waste disposed from the hydrogen peroxide plant as an adsorbent for the effective removal of fluoride from Fluoride attacked ground water at optimized contact time, adsorbent dose, and initial concentration by using response surface methodology (RSM). All batch scale experiments were carried out according to the statistical-design order. Central composite design (CCD) was applied to ascertain the effect of adsorbent dose, initial fluoride con centration and contact time on fluoride adsorption. The original deactivated alumina solid waste disposed from hydrogen peroxide plant; the sample were treated with Soxhlet extraction with a mixture of methanol and ethyl acetate, caustic soda treatment followed by thermal treatment at a temperature of 500 0C. The prepared deactivated alumina was characterized using XRD, SEM, FTIR and UV-DRS techniques. The characterization result confirms that the prepared adsorbent found to be crystalline, absorbs light in the visible and UV-DRS region. The FTIR results show the presence of various functional groups such as carboxylic acids, ketones, aldehydes and related. The SEM images and XRD patterns of the adsorbent were recorded to get a better insight into the adsorption process. The effects of experimental parameters such as contact time, dosage of adsorbent and initial concentration of fluoride were thoroughly investigated. The maximum fluoride removal efficiency (92.61%) was obtained at adsorbent dose of 2 g, contact time 90 min, and initial fluoride concentration of 5 mg/L. The adsorption result fitted well with pseudo-second order kinetic and Freundlich model. The current study reveals that the prepared deactivated alumina waste was found to be highly effective in removing fluoride ion from flouring containing ground water sources.