Rapid determination of chromium in natural waters by chemiluminescence with a centrifugal fast analyzer

Portable centrifugal analyzer for the determination of rapid reaction kinetics

“…Figure 11 illustrates the chemiluminescent emission from the reaction under conditions similar to those reported by Bowling et al (17). Because of limitations of both instrumentation and software, Bowling and co-workers could acquire a maximum of 21 sets of observations in a minimum time of ~2.5 s. In contrast, the portable centrifugal analyzer can acquire and process up to 99 successive observations (16)•, the time required (including that for rotor acceleration) is <2.8 s at 2000 rpm and <1.8 s at 3500 rpm.…”

“…Cr(IIL)/Luminol System. The procedure described by Bowling et al (17) was adapted for the portable centrifugal analyzer. A 100-mL sample [0.26 mg/L Cr(III) as Cr(N03)3-9H20] and 30 µ , of reagent [1.9 X 10~3 M luminol (5-amino-2,3-dihydro-l,4-phthalazinedione), 0.31 M H202, and 8.3 X 10"3 M EDTA in 0.10 M K0H/H3B03 buffer, pH 10.3] were loaded into a multicuvette rotor.…”

Brominating solution for the preconcentration of mercury from natural waters

“…Brominating Solution for the Preconcentration of Mercury from Natural Waters Sir: In recent papers, workers have reported the application of a brominating solution (1, 2) and bromine vapor (3) for the pretreatment of water samples prior to mercury determination by the cold vapor technique. The reagent makes available the Hg2+ ion from organomercury associations in the sample.…”

Enhancement of luminol chemiluminescence with halide ions

“…We have been concerned with the speciation of chromium in marine and freshwater environments. Previous studies have used only Cl analysis for the determination of Cr (III) in freshwater systems (1)(2)(3). While attempting to extend this technique to seawater analysis, we have determined that concentrated inorganic salt solutions can cause an enhancement of the Cl intensity.…”