A Test of the Local Equilibrium Assumption for Adsorption and Transport of Picloram

Reactive transport of gentisic acid in a hematite-coated sand column: Experimental study and modeling

“…The sorption behavior in batch and column studies has been found to be in agreement in some studies (Bond and Phillips, 1990;Gaber et al;1992;Hanna et al, 2009). Miller et al (1989 showed however higher distribution coefficients for column methods.…”

Ability of Single-Rate Models to Predict Solute Distribution Coefficients in Systems with Heterogeneous Sorption Kinetics

“…A leftward shift of the BTCs with increasing velocity has also been observed by others (van Genuchten et al 1974;Lee et al 1988;Gamerdinger et al 1990;Gaber et al 1992;Bouchard et al 1988;among others). This was interpreted as a reflection of the existence of inactive sorption sites at short residence times (van Genuchten et al 1974) or as an indication of the existence of extreme nonequilibrium conditions during transport (Brusseau and Rao 1989).…”

“…Several studies have reported discrepancies between the K values of organic compounds determined by batch and column techniques. In most cases, the batch-determined values were higher than their column-determined counterparts (Bilkert and Rao 1985;Celorie et al 1989;Gaber et al 1992;Piatt et al 1996;Maraqa et al 1998Maraqa et al , 2011Maraqa 2001a;Thorbjarnarson and Mackay 1994b;MacIntyre et al 1991;Carmichael et al 1999;Bouchard et al 1988;Perillo et al 1998;Thomsen et al 1999;Kazemi et al 2008;Hanna et al 2012). The level of discrepancy between the batch-and column-determined K varies from slight differences (Bouchard et al 1988;Celorie et al 1989;Maraqa et al 1998;Maraqa 2001a) to differences that reached orders of magnitude (Piatt et al 1996).…”

“…For the column method, K is calculated from the retardation factor, which is typically determined either by moment analysis of breakthrough curves (BTCs) (Thorbjarnarson and Mackay 1994a;Piatt et al 1996;Maraqa et al 1998;Maraqa 2001a) or by curve fitting a transport model to the breakthrough data. Both equilibrium (Gaber et al 1992) and nonequilibrium (Ptacek and Gillham 1992; Thorbjarnarson and Mackay 1994b;Maraqa et al 1998;Pot et al 2005;Dousset et al 2007;Maraqa et al 2011) transport models have been used for such a purpose, but the latter are more appropriate to use in many situations (Brusseau and Rao 1989).…”

Simulação do transporte e da sorção de imazaquin em colunas de solo

“…Valores diferentes de K d têm sido obtidos, quando se mantêm as condições experimentais, variando, apenas, a velocidade da água nos poros (Gaber et al, 1992;Chen & Wagenet, 1997;Beigel & Pietro, 1999).…”