ARSENIC REDUCTION IN DRINKING WATER WITH LOCALLY AVAILABLE HEMATITE ORE

Decontamination of water from contaminated sources is a global necessity that is implemented under the Global Sustainable Development Goals, number 6 (SDG 6). The quality of water is decreasing daily worldwide due to contamination and many people are exposed to drinking water contaminated by arsenic above 10 µg/L. Therefore, it is required to prepare simple methods for arsenic removal through the application of locally available materials, especially for low-income countries. The current study evaluates the performance of the locally available hematite ore to remove arsenic from water. The raw hematite collected from Kilua - Moshi Tanzania, calcined hematite, and ferric-hematite composite were investigated. The ferric composite was very efficient over raw and calcined hematite and it indicated 99.8% As removal after 4 hours. The calcined hematite at pH 7.5 reduced 1000 µg/L arsenic to 634 µg/L equivalent to 35.6% As removal after 4 hours. The natural water sample from Matongo, Nyamuhoto, Tarime district, Tanzania was treated with calcined hematite demonstrated the reduction from an initial 75 µg/L concentration of As (V) to 54.8 µg/L while As(III) increased 4 times to 0.435 µg/L. The raw hematite at pH 7.8 reduced arsenic to below 735 µg/L equivalent to 23% As removal after 2 hours. Therefore, the modified hematite ore can be an alternative solution to the reduction of As concentration to the guideline value of 10 µg/L recommended by the World Health Organization for drinking water especially in the low income countries.