Colloid–Trace Element Interactions in Aquatic Systems

Arsenic distribution in the dissolved, colloidal and particulate size fraction of experimental solutions rich in dissolved organic matter and ferric iron

“…Moreover, their stability in solution may change along flow paths and depends on surface charge and solution properties such as pH and ion concentration (Gschwend and Reynolds, 1987;Harvey et al, 1995;Kaplan et al, 1995;Doucet and Lead, 2007). Co-transport of contaminants by colloids has been recognized as an efficient mechanism of trace metal and organic chemical mobility (Kretzschmar and Sticher, 1997;Kretzschmar et al, 1999), but little attention has yet been paid to co-transport of As.…”

Influence of humic acid on plutonium sorption to gibbsite: Determination of Pu-humic acid complexation constants and ternary sorption studies

“…Commonly found coating the surface of inorganic material, NOM can change surface characteristics and affect mineral colloid stability and mobility [1]. The presence of dissolved NOM has been shown to result in the formation of stable Pu-NOM solution complexes and the reduction of Pu(V) to Pu(IV) [2][3][4][5][6][7].…”

Size, speciation and lability of NOM–metal complexes in hyperalkaline cave dripwater

“…Natural aquatic colloids are ubiquitous and are numerically the most abundant particles in natural waters, and irrespective of the system of interest the size distribution based on particle number (N) generally follows Pareto's law, i.e. in most natural waters there may be 10 6 times more 10 nm colloids than the equivalent number of 1 lm particulates (Filella and Buffle, 1993;Buffle and Leppard, 1995;Doucet et al, 2007). Colloids have a pervasive influence over the binding and transport of trace elements in soils and groundwaters McGechan, 2002) to the extent that for many metals, only a tiny fraction is 'free', i.e.…”