Natural organic matter that penetrates or does not penetrate activated carbon and competes or does not compete with geosmin

Super-fine powdered activated carbon (SPAC) for efficient removal of micropollutants from wastewater treatment plant effluent

“…S7, supplementary information). These observations are in line with past work showing that, though the fine grinding of particles increased the adsorption capacity of larger macromolecules such as DOM (Ando et al, 2010;Matsui et al, 2013bMatsui et al, , 2009a, the adsorption capacity for small micropollutants such as MIB, geosmin or phenol was not systematically increased, possibly because the adsorption of these smaller molecules occurred on the internal pores of the activated carbon (Ando et al, 2010;Matsui et al, 2013a). The greater adsorption capacity of Pulsorb SPAC relative to its parent PAC, may indicate alterations of the mesoporic structure during the wet milling process, possibly leading to increased numbers of adsorption sites available to the micropollutants.…”

“…The highest EfOM removal was observed for Norit SPAC (40% mg DOC/L) compared to 20% DOC removal by Norit PAC. Although higher DOM removals with SPAC in comparison to PAC have been reported previously (Ando et al, 2010;Matsui et al, 2013bMatsui et al, , 2012Matsui et al, , 2004, the same authors also found that low molecular weight (MW) micropollutants, namely geosmin and 2-methylisobornel (MW < 200Da) were not affected by the increased loading of DOM onto SPAC, as most of the DOM did not compete for the same sites as the targeted pollutants. Specifically, the authors suggested that low MW micropollutants preferentially adsorbed onto the interior surfaces of the carbon, whereas the larger MW DOM mainly adsorbs to the carbon surface (Matsui et al, 2013b).…”

Impact of Powdered Activated Carbon Structural Properties on Removal of Organic Foulants in Combined Adsorption-Ultrafiltration

“…On the other hand, the specific surface area, which corresponds to the ratio between a particle's external surface area per particle volume, of PAC is increasing. Due to diffusive limitations, particularly large organic molecules were reported to not completely penetrate PACs' inner structure but rather adsorb in a shell around the external surface of the particles [30][31][32]. A reduction in particle diameter will significantly increase the external surface area (see Table 2) and therefore provide larger surface for adsorption.…”

“…This confirms that the surface present in micro-pores, which contributes to a large portion of the total surface, does not affect NOM removal, especially if contact times are limited such as in combined PAC-UF. Previous studies showed that the main portion of organic water constituents is too large to diffuse into the carbon micro-porous structure [30][31][32]. Consequently, B.E.T.…”

Characteristics of natural organic matter removed from water along with its treatment

“…The NOM presence in treated water could also hinder coagulation process by stabilization of dispersed and colloidal particles thus increasing coagulant demand and water treatment cost [7,8]. Additionally, during adsorption on activated carbon, NOM competes with compounds harmful to humans such as pesticides, reducing removal efficiency of the latter [9]. NOM is also responsible for water color.…”