It is generally accepted that a low level of fluorine in mains water 0.4 to 1 mg -¢ L – 1 depending on the climate of the country concerned promotes the formation of tooth enamel and protects teeth from decay. On the other hand, too much fluorine will destroy this enamel and cause a range of endemic type disorders that are generally called “fluoroses- malformed teeth, staining of the enamel, decalcification, tendon mineralisation, digestive and nervous disorders, etc. These problems can appear in individuals for widely variable quantities of the product. Water must be discharged or treated as soon as it contains more than 1 to 1.5 mg -¢ L – 1 of F – . Some natural waters contain more than 10 mg -¢ L – 1 of fluorine. This concentration has to be reduced to approximately 1 mg -¢ L – 1 the acceptable concentration falling as the average annual temperature rises the European standard has set 1.5 mg -¢ L – 1. Many studies have been carried out to address the issue however little success has been reported up to date. Layered double hydroxides LDHs which readily undergo anion exchange reactions have been used as a suitable candidate for defluorination. Also there is regeneration of the material after removal of fluoride ions without releasing flouride ions back in to the water cycle. F elimination using a nanofiltration NF operation will solve problems for large scale pilot plants in the future.Many defluorination projects have significant effectiveness on the prevention of endemic fluorosis. The concentrations of water fluoride were below 1 mg L. Advanced on site methods, such as under sink reserve osmosis units, can remove fluoride but are too expensive for developing areas. Calcium carbonate as a cost effective sorbent for an onsite defluorination drinking water system. Batch and column experiments have been performed to characterize F removal properties. The present review discusses various techniques of defluorination of water. Dr. Atul Kumar Sharma | Dr. Harsukh Ram Chharang "Defluorination of Drinking Water" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-5 , August 2021, URL: https://www.ijtsrd.com/papers/ijtsrd46324.pdf Paper URL: https://www.ijtsrd.com/chemistry/other/46324/defluorination-of-drinking-water/dr-atul-kumar-sharma
International Journal of Trend in Scientific Research and Development (IJTSRD)
Volume 5 Issue 5, July-August 2021 Available Online: www.ijtsrd.com e-ISSN: 2456 – 6470
@ IJTSRD | Unique Paper ID – IJTSRD46324 | Volume – 5 | Issue – 5 | Jul-Aug 2021
Page 2224
Defluorination of Drinking Water
Dr. Atul Kumar Sharma
1
, Dr. Harsukh Ram Chharang
2
1Associate Professor, Department of Chemistry, S.D. Govt, College, Beawar, Rajasthan, India
2Associate Professor, Department of Chemistry, S.B.R.M. Govt. College, Nagaur, Rajasthan, India
ABSTRACT
It is generally accepted that a low level of fluorine in mains water
(0.4 to 1 mg • L–1 depending on the climate of the country
concerned) promotes the formation of tooth enamel and protects
teeth from decay. On the other hand, too much fluorine will
destroy this enamel and cause a range of endemic type disorders
that are generally called “fluoroses”: malformed teeth, staining of
the enamel, decalcification, tendon mineralisation, digestive and
nervous disorders, etc. These problems can appear in individuals
for widely variable quantities of the product. Water must be
discharged or treated as soon as it contains more than 1 to 1.5 mg •
L–1 of F–. Some natural waters contain more than 10 mg • L–1 of
fluorine. This concentration has to be reduced to approximately 1
mg • L–1 (the acceptable concentration falling as the average
annual temperature rises); the European standard has set 1.5 mg •
L–1.
Many studies have been carried out to address the issue however
little success has been reported up to date. Layered double
hydroxides (LDHs) which readily undergo anion exchange
reactions have been used as a suitable candidate for defluorination.
Also there is regeneration of the material after removal of fluoride
ions without releasing flouride ions back in to the water cycle. F−
elimination using a nanofiltration (NF) operation will solve
problems for-large-scale pilot plants in the future.
How to cite this paper: Dr. Atul Kumar
Sharma | Dr.