PATNA: Alum, locally known as ‘fitkari’ and a compound of aluminium, has long been used as ‘aftershave’ by common man owing to its antiseptic property. Now, yet another compound of aluminium — alumina — is likely to find even a greater use in the treatment of fluoride-contaminated water soon.
The findings of a recent study made jointly by the scientists of Nalanda University (NU) and Aryabhatta Knowledge University (AKU) have revealed that alumina could be a favourable material for optimal removal of fluoride ions from waste water. Adsorption of fluoride is a sophisticated but cheaper technology that requires adoption of suitable design and operational parameters for wastewater treatment, according to the study.
The findings of the research made by Rakesh Kumar and Prabhakar Sharma of School of Ecology and Environment Studies at NU and Abhay Kumar Aman and Rakesh Kumar Singh of the Centre for Nanoscience and Nanotechnology at AKU have been published in the September issue of international journal ‘Desalination and Water Treatment’.
Giving details of the findings, Rakesh said alumina is a ceramic oxide having the extensive potential for water purification, as it possesses unique properties, including high surface area and sorption capacity. The most important property of the compound on nano scale found during research was that an electromagnetic force becomes dominant between activated alumina and fluoride ions and due to this reason activated alumina was found to be a good adsorbent for wastewater treatment.
“X-ray diffraction and electron microscopy measurements indicated that materials in nano metre range facilitated fluoride desorption due to strong electromagnetic force and ion exchange. The reusability of activated alumina adsorbent makes the fluoride sorption cost-effective. So, the outcomes in this study establish that activated alumina can be efficient and appropriate adsorbent for sorption of fluoride ions from the contaminated water,” he said.
About 26 crore people are affected by fluoride contamination globally, including a sizeable population in India. The people of as many as 12 districts of Bihar, including Aurangabad, Banka, Buxar, Gaya, Jamui, Kaimur, Munger, Nawada, Rohtas and Supaul, are drinking fluoride-contaminated water (water having fluoride concentration in excess of the permissible limit of 1.5 mg/l). If this recent method of treatment of fluoride contaminated water is successful in treating the contaminated water at an affordable cost, it would certainly prove a boon for the poor people of the state, said Geological Survey of India’s retired director N Dayal.