Fluoride ion is present in high concentration in some regions in Syria. As
fluoride occurs naturally in water, We have studied some methods of fluoride
removal such as Nalgonda technique and activated carbon method.
In Nalgonda technique we add Al
um and lime to the water, and we have
found that fluoride removal efficiency remains constant when the initial
concentrations of fluoride changes, or when the chloride ions exists in water,
but it depends on pH, and get better when the method is investigated in two
steps. In addition, adsorption of fluoride decreases with increasing
sedimentation time, or using Ventilated lime or CaCO3 instead of Ca (OH)2.
In activated carbon method we have done different experiments by using
charcoal of coconut coir, date seeds and olive seeds. And we have found that
olive seeds carbon is better than others, and its fluoride removal efficiency
increases after impregnation with solution of 2% Al2(SO4)3.
