Toward a better extraction of titanium dioxide engineered nanomaterials from complex environmental matrices

Occurrence and removal of engineered nanoparticles in drinking water treatment and wastewater treatment processes: A review

“…Most TiO 2 -NPs and Ag-NPs released as byproducts of the aforementioned applications are treated in wastewater treatment plants, which are one of the essential ways of diverting ENPs from the environment [27]. Keller et al [28] used a mass flow model to derive the influent and effluent concentrations of TiO 2 -NPs and Ag-NPs in wastewater treatment plants, obtaining influent and effluent concentrations of 100-200 and 1-20 μg/L for TiO 2 and 2-18 and 0.003-0.26 μg/L for Ag, respectively.…”

Multistep Method to Extract Moderately Soluble Copper Oxide Nanoparticles from Soil for Quantification and Characterization

“…However, high natural Ti background made it difficult to differentiate between engineered and natural pools. Loosli et al also investigated the extraction of TiO 2 NPs from clay dispersions using inorganic chemical dispersants and got a maximum recovery of 45% after filtering clay/NP heteroaggregates . El Hadri et al adopted an extraction procedure based on standard leaching methods to extract Au NPs from various soils, but the maximum recovery of NPs was less than 15% .…”

“…Stabilization of colloidal dispersions by applying chemical dispersing agents has been studied extensively. − In this case, stabilization is defined as stability against aggregation by imparting either electrostatic or electrosteric repulsions resulting in a high dispersibility of particles. The most common dispersants are sodium polyphosphate-based salts (NaPP) which provides a repulsive force between colloids because of an increase in the particle’s surface charge. ,, Many of the studies that extract ENMs from natural waters or soils use NaPP as their stabilizer. However, the degree of electrostatic stabilization are heavily dependent on the specific water chemistry conditions (pH, ionic strength, presence of certain anions and cations, and TOC). − On the other hand, organic polymers and natural coatings, such as fulvic and humic acids, are also known to stabilize colloidal dispersions due to their steric and electrosteric properties. ,, However, a high Ca 2+ concentration can induce a bridging interaction between the cations and these organic polymers, enhancing aggregation .…”

“…Loosli et al also investigated the extraction of TiO 2 NPs from clay dispersions using inorganic chemical dispersants and got a maximum recovery of 45% after filtering clay/NP heteroaggregates. 20 El Hadri et al adopted an extraction procedure based on standard leaching methods to extract Au NPs from various soils, but the maximum recovery of NPs was less than 15%. 21 22 Instead, the dissolved and nanoparticle concentration were measured at the same time via single-particle inductively coupled plasma mass spectrometry (spICP-MS), which could hinder detection limits if the background baseline is elevated.…”

“…The most common dispersants are sodium polyphosphate-based salts (NaPP) which provides a repulsive force between colloids because of an increase in the particle's surface charge. 20,22,27 Many of the studies that extract ENMs from natural waters or soils use NaPP as their stabilizer. However, the degree of electrostatic stabilization are heavily dependent on the specific water chemistry conditions (pH, ionic strength, presence of certain anions and cations, and TOC).…”