Selective preconcentration of polynuclear aromatic hydrocarbons and polychlorinated biphenyls by in situ metal hydroxide precipitation.
An investigation of selective concentration of analytes from aqueous samples by in situ magnesium hydroxide precipitation, as described by Faltusz, has yielded the following results: the method is selective for polycyclic aromatic hydrocarbons and polychlorinated biphenyls of higher molecular weight: it discriminates strongly against acidic molecules, and other neutral and basic molecules are only partially recovered; a variety of metal hydroxides could evidently be used in this method, but magnesium appears to have practical advantages over some of the others; the reproducibility of analyses on pure water samples is acceptable (ca.20% relative standard deviation), but the results from natural samples show lower recovery and wider variability; a preliminary test, in which this method was used to discriminate against major amounts of interfering solutes, shows promise that this technique might have unique advantages in certain situations.
D055598:Chemical Phenomena; D002621:Chemistry; D002849:Chromatography, Gas; D006878:Hydroxides; D008276:Magnesium Hydroxide; D011078:Polychlorinated Biphenyls / Q000302:isolation & purification*; D011083:Polycyclic Compounds / Q000302:isolation & purification*
D006878:Hydroxides; D011083:Polycyclic Compounds; D011078:Polychlorinated Biphenyls; D008276:Magnesium Hydroxide