Studies on the use of powdered rocks and minerals for defluoridation of natural water Cyriac Bincy*, Balaji B.K., Satyanarayana K., Rai A.K. Atomic Minerals Directorate for Exploration and Research, Department of Atomic Energy, Nagarbhavi, Bangalore-560072, India *bincycyriac@rediffmail.com
Online published on 3 December, 2011. Abstract High fluoride content in drinking water has deleterious effects on the human health. Several methods are available for defluoridation, which, however, have some drawbacks. The present work aims to probe the possible use of compositionally diverse rocks and minerals for defluoridation purpose. It is demonstrated in this study that carbonate-rocks (limestone, dolostone and phosphatic limestone), compared to other rocks and minerals, are effective for defluoridation, thereby indicating that the bulk composition of the rock is critical in this regard. In case of minerals, the ability of the fluoride ion to get removed depends upon the refractory nature of the mineral as well as the affinity of fluoride to interact with the constituents of the minerals. It is also observed for the first time, during the preliminary study, that the residue obtained after alkaline leaching of uranium from brecciated limestone, performed as a better defluoridizing agent. This residue which would have been discarded as waste will be able to find application for defluoridation. In fact, the uranium mineralization in brecciated limestone that has been discovered in Gulbarga District of Karnataka state, India, can be used in the same state where fluoride rich water has been encountered The novelty of the study is that there is neither use of chemicals for defluoridation nor the requirement of pH-control for adsorption of fluoride. The findings have been successfully tried on a batch of water samples containing varying amounts of fluoride. Top Keywords Defluoridation, Powdered rocks and minerals, Ground water. Top |