Arsenic Contaminant

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Arsenic is the highly poisonous inorganic contaminants originating from either earth crust or anthropogenic activities. Arsenic caused both are severe and chronic health effects on the human body, such as respiratory, pulmonary, cardiovascular, gastrointestinal, dermal changes (pigmentation, hyperkeratoses, and ulceration), immunologic, hematological, genotoxic, mutagenetic, hepatic, renal and carcinogenic effect (kazoo T Suzuki et al 2002). According to the United States Environmental Protection Agency (US EPA) maximum arsenic contaminant level (MCL) is now decrease 50 to 10 micrograms per liter.[US EPA. Minor clarification of National Primary Drinking Water Regulation for arsenic] .Due to adverse health effect of arsenic, in the last few …show more content…

0.1, 0.5 and 1 gm NZVI/AC was taken into diff conical flask. Each conical flask containing 500 ml of 2 mg/l As solution. Initial pH of this solution was adjusted at 6.5 with the help of buffer .1 Mol/l HCL or NaOH. For the isotherm study use Boyd model. At ph 6.5 nearly 94.3% as(iii) and 65.3% as(v) was removed in first 12 hours of removal process but there adsorption equilibrium was achieved in 72 hours which gave approx. 100 % removal of as. This study also shows that if dose of NZVI/AC applied increases from 0.1 to 3 g/l then as removal of arsenate and arsenate increase from 68 and 57 % to 100 %. As removal by nzvi/ac is fallen from pH 3 to pH 12 whereas the removal of as from arsenate solution increases from pH3 to 6.5 and decreases rapidly below pH 9. The two line meet at pH 4.5. above this pH value as removal eff was much more for arsenate. It indicates nzvi/ac is superior for removal of as(iii) at diff pH of ground water. Adsorption of arsenate on nzvi/ac decreases from neutral to alkaline media while for arsenate it increases in acidic media and decreases in alkali media. In this case pH of zero point charge obtained at pH 7.4 . at pH <9, arsenate species are H3AsO3 is predominant and in pH range 9-12 H2AsO3- is predominantly available in drinking water. If iron used in activated carbon by 4.22% then iron filled AC increases removal of arsenic but if % of iron in AC …show more content…

A 100ml solution containing 0.16gm FeCl3,0.1 gm PEG and 0.1 gm Fecl2.4H2O is mixed at 65 C and pH of this solution was slowly increased upto 10 by adding 25 % of NH3. After one hour of at 70 C suspension was washed. Finally this modified activated carbon fibre cloth (MACF) is dried in an oven at 102 C for two hours. The adsorbent dosage was applied in the range of 0.6 to 0.7 gm per litre. This adsorbent were added into 50ml of arsenate solution with an as(v) concentration of 2mg for evaluation of adsorption efficiency after shaking of solution at room temp. for 24 hr sample solution filtered through a .45 micro meter for adsorption isotherm experiments conducted t pH 4 and pH effect experiment are done ranging from 1.8 to 11.6 at a constant concentration 2mg/l. Batch process is conducted to obtained the pH of point of zero charge (pHpzc) of the RACF and the MACF. Different amount of NaNO3 solutions of 1mili M with several pH values and prepared with mixing diluted HNO3 or NaOH . ACF cloths has 0.05 g weight was added into 18 mL NaNO3 solutions. After mixing it properly in PVC vials for 24

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