This paper presents a comparative review of arsenite (As(III)), arsenate (As(V)), and fluoride (FâË?â??) for a better understanding of\nthe conditions and factors during their adsorption with focus on (i) the isotherm adsorption models, (ii) effects of pH, (iii) effects\nof ionic strength, and (iv) effects of coexisting substances such as anions, cations, and natural organics matter. It provides an indepth\nanalysis of various methods of arsenite (As(III)), arsenate (As(V)), and fluoride (FâË?â??) removal by adsorption and the anionsââ?¬â?¢\ncharacteristics during the adsorption process. The surface area of the adsorbents does not contribute to the adsorption capacity of\nthese anions but rather a combination of other physical and chemical properties.Theadsorption capacity for the anions depends on\nthe combination of all the factors: pH, ionic strength, coexisting substances, pore volume and particles size, surface modification,\npretreatment of the adsorbents, and so forth. Extreme higher adsorption capacity can be obtained by the modification of the\nadsorbents. In general, pH has a greater influence on adsorption capacity at large, since it affects the ionic strength, coexisting\nanions such as bicarbonate, sulfate, and silica, the surface charges of the adsorbents, and the ionic species which can be present in\nthe solution.
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