Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Water Is Purified From Fluorine

15.03.2004


Researchers of the Kola Scientific Center, Russian Academy of Sciences, have developed an efficient method for sewage water purification from fluorine ions. Fine purification of water can be achieved through utilisation of sorbents containing titanium. In addition, the method solves the problem of recycling spent sorbents saturated with fluorine.



The majority of contemporary toothpastes contain sodium fluoride as a fluoridiser agent to reinforce enamel. In the natural environment, this substance is found in the form of transparent deep cherry-coloured crystals called williomits after a French traveller, whose collection of minerals from Guinea was the first to reveal this crystal.

Williomits get washed out, this causing the fluorine ions’ presence in the water. Normally, their concentration should not exceed 1.4 milligram per litre of water, however, the fluorine content should be twice lower that that in the water intended for fish industry activity: the fish accumulate fluorine in the organism and then it is consumed by people. The substance which in small amounts is contained in the toothpaste and strengthens the teeth has become the reason for serious problems in Kola Peninsula and other regions, where mining enterprises work intensely to process ores containing williomits.


This results in millions of cubic metres of sewage with high content of fluorine ions, their concentration exceeding the maximum allowable concentration by ten times, and this is very dangerous for human health. Abundant fluorine content in the organism may cause the fluorosis disease. As a result, the enamel decays, white spots appear on the enamel and turn yellow as time passes. In addition, abundant fluorine inhibits some enzymes’ action in the organism. Poison is curative only in small dozes.

So far, there has been no inexpensive and efficient technology for water purification from fluorine ions. Researchers from the Tananaev Institute of Chemistry and Technology of Rare Elements and Mineral (Kola Scientific Center, Russian Academy of Sciences) suggested that various titanium compounds should be used as sorbents: titanyl hydroxides or sulphates, which tightly bind fluoride ions.

For example, when processing the mineral which contains titanium, it is easy to get titanyl sulphate that can be efficiently used to purify water from ions of fluoride. This compound is added to the sewage water while mixing, it dissolves rather easily, and then, as a result of hydrolysis, it turns into the loose deposit. It is the deposit that plays the role of sorbent in purification of water from ions of fluoride.

After such processing, sorbents containing fluorine in the form of deposit can be simply filtered. This method provides for fine purification of water, decreasing the flurine ion content down to 0.5-0.6 milligram per liter, which poses no threat to human health. For example, if the water contains 10 milligrams of fluorine ions per liter, then processing of one liter of such water would require 80 milligrams of titanyl sulphate.

The new water purification method also solves the problem of disposal of spent sorbents with fluorine ions contained in them. Previously, fluorine saturated sorbents, accumulated, and fluorine penetrated the soil and contaminated the environment. Under the new method, spent solid sorbents may be processed with sulphuric acid, thus getting valuable hydrogen fluoride and fresh portions of water soluble titanyl sulphate, which can be reused. Therefore, the method suggested by the researchers will allow to purify water from fluorine, to obtain a valuable chemical product and to save sorbent.

Sergey Komarov | alfa
Further information:
http://www.informnauka.ru

More articles from Ecology, The Environment and Conservation:

nachricht Bioinvasion on the rise
15.02.2017 | Universität Konstanz

nachricht Litter Levels in the Depths of the Arctic are On the Rise
10.02.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Impacts of mass coral die-off on Indian Ocean reefs revealed

21.02.2017 | Earth Sciences

Novel breast tomosynthesis technique reduces screening recall rate

21.02.2017 | Medical Engineering

Use your Voice – and Smart Homes will “LISTEN”

21.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>