Nanoparticles For Water Treatment Research Articles

Synthesis and Application of Novel Functionalized Nanostructured Membranes Incorporating N-doped CNT Supported Metal Nanoparticles in Water Treatment

Synthesis and Application of Novel Functionalized Nanostructured Membranes Incorporating N-doped CNT Supported Metal Nanoparticles in Water Treatment

Synthesis of Polyacrylic Acid Stabilized Amorphous Calcium Carbonate Nanoparticles and Their Application for Removal of Toxic Heavy Metal Ions in Water

We report an efficient method for synthesis of poly(acrylic acid) stabilized amorphous calcium carbonate nanoparticles (ACC) and their application for removal of toxic heavy metal ions from aqueous solutions. The maxium removal capacities for Cd2+, Pb2+, Cr3+, Fe3+, and Ni2+ ions were found to be 514.62 mg g−1, 1028.21, 258.85, 320.5, and 537.2 mg g−1, respectively. The distinguishing features of the ACC nanoparticles in water treatment involve not only high removal capacities, but also decontamination of trace ions. Approximately 83.0% on average removal can be achieved in the treatment of polluted water containing trace amount of radioactive Eu3+ ions. A precipitation transformation mechanism is proposed to play a key role in such water treatment.

Impact of Nanoparticles and Natural Organic Matter on the Removal of Organic Pollutants by Activated Carbon Adsorption

Isotherm experiments evaluating trichloroethylene (TCE) adsorption onto powdered-activated carbon (PAC) were conducted in the presence and absence of three commercially available nanomaterials: iron oxide (Fe(2)O(3)), titanium dioxide (TiO(2)), and silicon dioxide (SiO(2)). Isotherm experiments were also conducted in the presence and absence of natural organic matter (NOM), in the form of humic acid, to more closely model natural water conditions. Nanoparticles at two concentration levels (0.5 and 1.0 mg/L for Fe(2)O(3) and TiO(2), and 5.0 and 10 mg/L for SiO(2)) were considered. Zeta potential and pH of point of zero charge (pH(pzc)) of the nanoparticles and the PAC were measured. Particle size distribution (PSD) of the nanoparticle dispersions was analyzed as a function of time to determine the nanoparticle size range of each dispersion. Aggregation of Fe(2)O(3) and TiO(2) nanoparticles was observed but not for SiO(2) nanoparticles. Adsorption isotherm experiments were conducted at three initial TCE concentrations, two nanoparticle concentrations, and with varying amounts of PAC. Isotherm data showed a higher degree of adsorption in the presence of Fe(2)O(3) and TiO(2) nanoparticles, regardless of concentration. In activated carbon-free experiments both Fe(2)O(3) and TiO(2) nanoparticles alone were observed to act as adsorption sites for TCE by removing up to 60% of TCE from the aqueous phase. Silica appeared to have no impact on TCE adsorption at either of the concentrations evaluated, except in the presence of humic acid. This study provides important information related to the use of nanoparticles in water treatment and their impact on the performance of a commonly used adsorbent used to remove organic pollutants. No studies to date have attempted to quantitatively describe the adsorption behavior of TCE to PAC in the presence of TiO(2), SiO(2), and Fe(2)O(3) nanoparticles.