NOM-facilitated transport of metal ions in aquifers: importance of complex-dissociation kinetics and colloid formation

Modification of ultrafiltration membrane with nanoscale zerovalent iron layers for humic acid fouling reduction

“…HS are commonly existed in natural waters in the range of a few mg/L to a few hundred mg/L C (Wall and Choppin, 2003). However, the presence of HS could cause various environmental and health problems including the followings: (1) HS could cause undesirable color and taste, which are also served as food for bacterial growth in water (Bai and Zhang, 2001); (2) HS could bind with heavy metals and biocides, yielding high concentration of these substances and enhancing their transport in water (Schmitt et al, 2003); (3) HS could react with chlorine during water treatment to form disinfection by-products, such as trihalomethane (Tian et al, 2013); (4) HS have been shown to compete with low MW synthetic organic chemicals and inorganic pollutants, reducing their adsorption rates and equilibrium capacities (Tratnyek et al, 2001;Klausen et al, 2003); (5) HS could act as a major foulant causing serious microfiltration (MF)/ultrafiltration (UF) membrane fouling during filtration Zydney, 1999, 2000). As such, the removal of HS has been widely investigated to minimize their impact on environmental and human health.…”

Dissolved Organic Matter (DOM) in Natural Environments

“…Donnan membrane technique on gibbsite suspension can be used to study the Al complexation in natural waters (Weng et al, 2002 ). Metal complexation by DOM has also shown to be of great importance for describing transport processes (Schmitt et al, 2003 ). Here the sorption of DOM on geosorbents plays an important role Weng et al, 2006 ).…”

Effects of Pretreatments on Calcium Accumulation Onto Gac

“…In natural aquatic systems, inorganic ions are rarely present as free hydrated ions [Buffle, 1988]. Complex formation is one of the most important reactions of inorganic ions in aquatic systems and NOM is an important complexing agent for inorganic ions and therefore for calcium [Schmitta et al, 2003;Christensen et al, 1996]. It has been proven that calcium accumulation onto GAC is negligible in the absence of NOM.…”