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With the surface water and groundwater arsenic pollution increasing as well as the National Standardization Management Committee and the People's Republic of China Ministry of Health to accept more and more stringent standards (down from the current level of 50μg / L to 10μg / L), the current arsenic removal method does not fully meet this requirement, it is particularly necessary to develop new, cost-effective arsenic removal technology. In this paper, this hot, through the process compared with potassium permanganate Cooperative ferrous sulfate process enhanced to remove arsenic from drinking water, mainly inspected the various parameters of the process, the influence of coexisting ions in the water and arsenic removal mechanism conducted a preliminary study. The experiment using distilled water with water, controlling the pH value to the water dosing the desired amount of arsenic, fixed ionic strength and alkalinity. The results indicate that potassium permanganate - ferrous sulfate process has very good synergy arsenic removal effect. Dosage of ferrous sulfate 2.5mg Fe / L, pH = 5, oxidation 2min the coagulation 1min, flocculation 20min arsenite (As (III) = 1mg / L), Mn / As molar ratio of 1.4; For arsenate (As (V) = 0.984mg / L), Mn / Fe molar ratio of more than 0.2 when both can be made up to 99% removal efficiency. The process by the pH value, reduce with the rise in pH, potassium permanganate - ferrous sulfate process in addition to the efficiency of As (III). Coexist in the water by potassium permanganate oxidation of ferrous ions (Fe (II)), As (III) is also able to obtain a better effect in addition to As (III); at pH = 5, the presence of manganese ions of As (III) removal had no significant effect. In addition, this process has a strong ability to adapt to different water bodies. Was found that the coexistence of calcium ions in the acidic conditions in water, silicates inter As (III) effect, affect obvious, but neutral, under alkaline conditions, the former can promote the As (III) the removal of the latter exhibited greatly inhibition. In the entire pH range of phosphate on the removal of arsenic to exhibit a strong inhibitory effect, the humic acid has a similar effect in addition to pH = 4 points. In the process, the actual need of potassium permanganate is not better, but must meet the oxidation of As (III), ferrous sulfate, the new eco-iron and arsenic performance is significantly better than the ferric sulfate. Iron, manganese mainly through adsorption, coprecipitation the role removal of arsenic, showed very good synergy. Respect to the dosing of As (V) As (V), the new ecological more easily removed. Potassium permanganate - ferrous sulfate process showed good performance for removing arsenic from water, and has the advantage of efficient, economical, and convenient technology to remove arsenic contamination of drinking water is an intensive suited to China's national conditions.
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