title: Quantification of trace metals in water using complexation and filter concentration.
abstract: Various metals undergo complexation with organic reagents, resulting in colored products. In practice, their molar absorptivities allow for quantification in the ppm range. However, a proper pre-concentration of the colored complex on paper filter lowers the quantification limit to the low ppb range. In this study, several pre-concentration techniques have been examined and compared: filtering the already complexed mixture, complexation on filter, and dipping of dye-covered filter in solution. The best quantification has been based on the ratio of filter reflectance at a certain wavelength to that at zero metal concentration. The studied complex formations (Ni ions with TAN and Cd ions with PAN) involve production of nanoparticle suspensions, which are associated with complicated kinetics. The kinetics of the complexation of Ni ions with TAN has been investigated and optimum timing could be found. Kinetic optimization in regard to some interferences has also been suggested.
authors.affiliation: Nuclear Research Center Negev, Beer Sheva, Israel.
authors.forename: Bella
authors.initials: B
authors.lastname: Dolgin
authors.forename: Valery
authors.initials: V
authors.lastname: Bulatov
authors.forename: Julia
authors.initials: J
authors.lastname: Japarov
authors.forename: Eyal
authors.initials: E
authors.lastname: Elish
authors.forename: Elad
authors.initials: E
authors.lastname: Edri
authors.forename: Israel
authors.initials: I
authors.lastname: Schechter
mesh_terms: D002104:Cadmium / Q000737:chemistry; D002623:Chemistry Techniques, Analytical; D002625:Chemistry, Organic / Q000379:methods; D004784:Environmental Monitoring / Q000379:methods*; D005374:Filtration; D006863:Hydrogen-Ion Concentration; D007477:Ions; D007700:Kinetics; D008670:Metals / Q000737:chemistry; D046529:Microscopy, Electron, Transmission / Q000379:methods; D009532:Nickel / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D014131:Trace Elements / Q000032:analysis*; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D007477:Ions; D008670:Metals; D012997:Solvents; D014131:Trace Elements; D014874:Water Pollutants, Chemical; D002104:Cadmium; D014867:Water; D009532:Nickel