Arezoo salamatnia - PhD of Spatial Environment , Islamic Azad University , Nourth Tehran Branch ,Iran

There are small amounts of fluoride in water, air, plants and animals. Humans can receivefluoride through food, drinking water and breathing. In regions where the natural waternormally contains high levels of fluoride and the intake is 2 to 8 times greater thannormal volume, dark black spots can be seen on the teeth. Nevertheless, the moreimportant issue is extremely high fluoride intake (twenty to forty times more than normal)which causes abnormal development and stiffness of bones known as bone selerosis, andalso calcification of ligaments known as fluorosis disease.Furthermore, the main focus has always been on the level of bacteria found in drinkingwater. Groundwater is regarded as a healthy source for drinking, while there is littleconcern with the dangers of chemical contamination of groundwater including fluoride.This study attempted to employ surface adsorption for the removal of fluoride from waterthrough absorbent bauxite. Bauxite was extracted from Jajrom mines by the aluminumcompany Iran Alumina Co. in 2018. Batch experiments were carried out to achieveoptimal operating conditions for fluoride absorption. The results suggested that initialconcentration of fluoride at 5 milligrams per liter, contact time of 75 minutes, theadsorbent concentration of 10g/100ml and the pH of 6 could provide the optimal fluorideabsorption through bauxite. Moreover, the concentration data from Langmuir model weremore functional than those from Freundlich model.

fluoride removal, bauxite, surface absorption, drinking water