Chromate and oxalate adsorption on goethite. 2. Surface complexation modeling of competitive adsorption

Surface Complexation Modeling of Organic Acid Sorption to Goethite

“…c pK a values for 1-hydroxy-2-naphthoic acid and 2,7-dihydroxynaphthalene were not available in the literature and were estimated using pK a values for structurally similar compounds. similar to those proposed by to fit data for phthalic and chelidamic acid sorption to goethite and Mesuere and Fish (10,11) to fit data for oxalate sorption to goethite.…”

Sorption of aqueous carbonic, acetic, and oxalic acids onto α-alumina

“…This adsorption maximum seems to be explained by suitability between complexing agent charge and surface charge. Moreover, all authors observe a competitive effect of chloride in adsorption onto oxide minerals [4,6], meaning that the site for sorption is identical for both. But some uncertainties remain concerning the adsorption mechanisms.…”

“…But some uncertainties remain concerning the adsorption mechanisms. If most of them explain their results by ligand exchange mechanism between deprotonated form and surface hydroxide, in the case of oxalic acid and carbonic acid, some authors use only totally deprotonated ligand [7] and others use both deprotonated forms [6].…”

Adsorption of Cr(VI) from synthetic solutions and electroplating wastewaters on amorphous aluminium oxide

“…In this way, adsorption appears as a highly promising alternative to purify such wastewaters. Several studies have been reported using different low-cost adsorbents for the Cr(VI) removal, including activated carbon [8,9], wool [10], agricultural byproducts such as coconut husks and palm pressed fibres [11], sugar cane bagasse, sugar beet pulp, maize cob, saw dust, olive cake, pine needles, almond shell and cactus leaves [12,10], waste materials such as fly ashes [13], red mud [14,15] and biogas residual slurry [16] and minerals such as feldspar [17], hydrotalcite-like compounds [18][19][20][21][22], crystalline iron oxyhydroxides [23][24][25][26][27][28][29] and ␥-Al 2 O 3 [30,31]. From the light of these studies adsorption emerges as a robust and versatile method that could solve the problems of sludge handling and render the purification system more economically viable, especially if lowcost adsorbents are involved.…”