Removing Fluoride from Drinking Water

Fluoride is a particularly challenging substance to remove from water, even more so than chlorine or heavy metals. Currently, there are two mainly methods for fluoride removal: specialized fluoride-removing filter media and reverse osmosis membrane technology.

1. Zeolites: Stilbite, a type of natural zeolite, features high crystallinity and an open pore system. Its crystal structure contains numerous open pores and channels of varying sizes occupied by cations and water molecules. The water molecules in the channels can reversibly adsorb and desorb fluoride without damaging the zeolite’s crystal structure. Under ideal conditions, it can reduce fluoride levels to below 1 mg/L.

2. Bone char: Derived from animal bones and transformed into a type of carbon, bone char has a carbon structure with a large surface area and excellent adsorption properties. The hydroxyapatite in bone char adsorbs fluoride ions in water, forming calcium fluoride, thereby achieving fluoride removal. The fluoride removal capacity of bone char is 1.68 mg/g, and its effectiveness is influenced by various factors, including the original fluoride ion concentration, bone char particle size, pH, water temperature, and the presence of other ions in the water. Under ideal conditions, it can reduce fluoride by about 70%. However, bone char is not favored by vegetarians.

3. Ion exchange media: Many ion exchange media are specifically designed for industrial applications. Although there are specific ion exchange resins for fluoride removal, there is a risk of fluoride leakage when these resins become saturated.

4. Activated alumina: Activated alumina is an inorganic material with strong fluoride adsorption capacity and the ability to catalyze fluoridation reactions. It can remove fluoride from water through a chemical reaction between fluoride ions and the surface of aluminum oxide.

5. Reverse osmosis membrane technology: If the sole purpose is to remove fluoride, reverse osmosis membrane technology is also an option. However, the removal rate is related to the fluoride concentration in the water, pH, and the material of the reverse osmosis membrane.

Each of these methods has its advantages and disadvantages. When treating fluoride in water, it is necessary to select the appropriate method based on the specific circumstances to achieve the best results.

Disclaimer:
Information and statements made on this web are for education purposes and are not intended to replace the advice of your doctor.
The products mentioned here are not intended to diagnose, treat, cure or prevent any disease or health condition.No medical claims are being made.