Sorption of organics on clay and synthetic humic-clay complexes simulating aquifer processes

Enhanced photocatalytic degradation of pollutants in petroleum refinery wastewater under mild conditions

“…Several solutions are proposed in this regard; including use of coagulants [1,2], coagulation enhanced by centrifugation [3], ultra filtration [4,5] or sorption on organo-minerals [6]; with a level of advantage for each of them.…”

Surface binding site analysis of Ca2+-homoionized clay–humic acid complexes

“…However, very few studies have quantified humic sorption onto the clay surface [4,5,13,[23][24][25][26][27]. Humic substances are mixtures of polydisperse, heterogeneous polyelectrolytes [23,[28][29][30].…”

Sorption of Atrazine by Al- and Ca-Saturated Smectite

“…For example, Farrell and Reinhard (1994) observed that, at 100% RH, montmorilllonite SWY-1 sorbed as much as 10 -5 mol g-1 (1300 ppm) of various hydrocarbons. Similarly, sorption of varying amounts of di-and trichlorobenzenes by kaolinite (Schwarzenbach and Westall 1981) and montmorillonite (Rebhun et al 1992) and of atrazine by smectites (Laird et al 1992) in aqueous suspensions have been observed. Adsorption of the nonionic organic compounds is generally attributed to hydrophobic interactions on siloxane surfaces (Chen 1976) on basal planes of the phyllosilicates.…”

“…In low organic matter soils and sediments, however, clay minerals likely control the sorption/desorption interactions (Mingelgrin and Gerstl 1983;Hayes and Mingelgrin 1991). Investigations into sorption of organic contaminants of a wide range of hydrophobicities (Rebhun et al 1992) by clays and clay-humic complexes showed that adsorption constants for humic (organic) fraction was 8 to 20 times higher than the pure clay minerals. However, in soils with the commonly encountered range of organic matter (0.5-5%) and high clay content, the contribution of the mineral fraction appeared to exceed that of the organic component.…”