Around the world, it is estimated that tens of millions of people are affected by both dental and skeletal fluorosis. In many cases, it is the addition of fluoride into drinking water supplies by governments that is the primary cause of both dental and skeletal fluorosis.
Common techniques used for defluoridation are coagulation-precipitation, membrane process and ion exchange.
The problem with these three techniques is that they are either too expensive or they further pollute the water.
Researchers from the National University of Sciences and Technology in Pakistan have discovered an effective method to remove fluoride from drinking water that is less expensive than conventional filtration processes and is safe to use.
The study, published in the Journal of Chemistry, concluded that the removal of fluoride from drinking water using modified immobilized activated alumina (MIAA) resulted in a removal efficiency that was 1.35 times higher than normal immobilized activated alumina.
Modified immobilized activated alumina (MIAA) was added to water that was tainted with fluoride and then analysis was conducted to evaluate the quantity of fluoride that was removed from the water.
Effect of an adsorbent dose on the removal of fluoride at 20 ± 1°C.
It was discovered that MIAA, at 20 +/- degrees celsius has the capacity to remove more than 95% of fluoride from water. In fact, the adsorption capacity of MIAA was much higher (0.76 mg/g) when compared to the adsorption capacity of activated charcoal (0.47 mg/g) for the same concentration fluoride samples.
The adsorption method that is used by modified immobilized activated alumina (MIAA) is much more cost-effective (Ali, I., & Gupta, V. K. (2007) Advances in water treatment by adsorption technology. Nature Protocols) than the popular Reverse Osmosis Filtration method.
Considering that both MIAA and Reverse Osmosis Filtration remove more than 90% of fluoride, MIAA could be a viable alternative to removing fluoride from drinking water supplies in developing countries.
Unfortunately, there are some limitations to the use of MIAA in removing fluoride from drinking water. The greatest challenge in the use of MIAA for removing fluoride from drinking water is filtering MIAA once all fluoride has been absorbed.
Real water samples with initial fluoride concentration and final concentration.
However, considering that the granules produced by MIAA varied from 3 to 6 mm, all that was required during the study to remove the MIAA granules from the water was basic water filtration.
Ultimately, the primary challenge faced when trying to removing fluoride from drinking water is cost.
The use of modified immobilized activated alumina (MIAA) to remove fluoride from drinking water could become a viable option that would enable communities in both developed and developing nations to remove fluoride from drinking water.
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