Sorption of arsenate and dichromate on polymerin, Fe(OH)x-polymerin complex and ferrihydrite.
Dihydrogenarsenate [H(2)AsO(4)(-), As(V)] or dichromate [Cr(2)O(7)(2-), Cr(VI)] at pH=4.0 showed to be sorbed on a Fe(OH)(x)-polymerin complex and ferrihydrite to a greater extent than on polymerin, the organic polymeric fraction of olive oil mill wastewater (OMW). In particular, the maximum amount (x(m)) of arsenate sorbed on Fe(OH)(x)-polymerin complex was similar to that on ferrihydrite (880.26 and 743.02 mmol kg(-1), respectively), and was much greater than that sorbed on polymerin (384.25 mmol kg(-1)). The sorption of dichromate was to a comparable extent on Fe(OH)(x)-polymerin complex and ferrihydrite (205.90 and 254.88 mmol kg(-1), respectively). Cr(III), a less toxic chromium form, mainly, and Cr(V) were indeed the effective forms sorbed on polymerin (200 mmol kg(-1)), as a consequence of the redox reaction of the strongly toxic Cr(VI) with the CH(2)OH groups of the polysaccharide moiety of this bio-sorbent, according to the data deriving from XPS and DRIFT analyses. The potential exploitation of the selected sorbents for the removal of As(V) or Cr(VI) from aqueous effluents is briefly discussed.
Sannino
F
F
School of Biotechnological Sciences, Department of Soil, Plant, Environment and Animal Production Sciences, Via Università 100, Università degli Studi di Napoli Federico II, 80055 Portici, Naples, Italy.
De Martino
A
A
Pigna
M
M
Violante
A
A
Di Leo
P
P
Mesto
E
E
Capasso
R
R
D000327:Adsorption; D000838:Anions; D001149:Arsenates / Q000302:isolation & purification*; D002840:Chromates / Q000302:isolation & purification*; D005290:Ferric Compounds / Q000737:chemistry*; D007220:Industrial Waste / Q000517:prevention & control*; D010084:Oxidation-Reduction; D011108:Polymers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
D000838:Anions; D001149:Arsenates; D002840:Chromates; D005290:Ferric Compounds; D007220:Industrial Waste; D011108:Polymers; D014874:Water Pollutants, Chemical; C021024:ferric hydroxide; C092844:ferric oxyhydroxide