Fluoride is a toxic mineral. It is often found in drinking water. The current international drinking water standard for fluoride set by the World Health Organization (WHO) is 1.5 ppm. High fluoride levels can cause dental and skeletal fluorosis, so excess fluoride must be removed from drinking water. Among the various water treatment chemicals available, polyaluminium chloride (PAC) is the first choice for fluoride removal. PAC’s fluoride removal ability stems from its unique chemical properties and mechanism of action. Let’s explore its mechanism, advantages and applications.
Mechanism of action of polyaluminium chloride:
Polyaluminium chloride is an inorganic coagulant produced by the reaction of aluminium hydroxide and hydrochloric acid. It is often used as a flocculant in municipal and industrial water treatment processes.
Polyaluminium chloride electrostatically adsorb and combine with fluoride ions to form a variety of stable complexes. This then further forms and precipitates insoluble aluminium fluoride.
Aluminum ions and fluoride ions can also form a variety of stable complexes (such as , reducing the concentration of free fluoride in water.
Advantages of PAC as a defluoridant
High efficiency: PAC can achieve significant fluoride removal rates, usually exceeding 90% under optimal conditions. Compared with traditional aluminum salts, PAC has a higher charge density and a faster flocculation rate. The defluoridation efficiency is increased by 30% at the same dosage.
Economic: The treatment cost is reduced by more than 40% compared to technologies such as reverse osmosis, and no complex equipment is required.
And the pH application range is wide (5.0-9.0). And the turbidity of water can be reduced simultaneously.
Low sludge production: Less sludge is formed, which is easier to manage.
Notes on PAC as a defluoridant:
PAC performs best at slightly acidic to neutral pH values (about 6.5 to 7.5). Maintaining the proper pH value ensures maximum fluoride removal.
The removal of fluoride depends on the initial fluoride concentration and the dosage of the coagulant.
Application of PAC in Fluoride Removal
Municipal water treatment: Ensure drinking water safety by reducing fluoride to acceptable levels.
Industrial wastewater treatment: Remove fluoride from wastewater generated by industries such as glass manufacturing, semiconductor production and fertilizer plants.
Ecological restoration: Treat groundwater and soil contaminated by natural fluoride to protect the ecological environment.
Agricultural and environmental restoration: Remove Fluoride ions from irrigation water to avoid soil salinization and crop damage.
Polyaluminum chloride is a proven and effective solution for fluoride removal in water treatment applications. Its ability to condense and adsorb fluoride ions makes it a first choice in municipal and industrial environments. It is very important to choose a reliable chemical supplier among many PAC suppliers. You need to verify their qualifications and product quality. If you need any assistance in purchasing PAC, please let me know. We can provide free samples and selection services. Looking forward to seeing you!
Post time: Apr-03-2025