Analytica Chimica Acta, 1997, Vol.349(1), pp.93-99
The paper describes the development of two different techniques for the automated determination of uranium by adsorptive stripping voltammetry (AdSV). As a complex forming reagent 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone (chloranilic acid) is used. The automation was performed in one case using an auto-batch system and in the second case by means of a flow-through cell. Sensitivities, reproducibilities and the fields of application are evaluated. The auto-batch technique, with the automatic standard addition capability as well as its logical decision-making capacity for selecting the correct type of working electrode makes it highly suitable for the determination of varying uranium concentrations above 1 μg/l. The dilution of the sample, required by the methodology, makes determinations of uranium concentrations less than 1 mg/l unattainable. The flow-through technique is more suited to determine uranium at the ultra trace concentration level (above 70 ng/l). Provided the matrix is reasonably constant, a pre-determined calibration curve can be used and, due to the higher slope of the calibration plot in the flow-through technique, the linear concentration range extends to a lower concentration compared to stationary conditions. Another advantage of the flow-through technique is the possibility of kinetic and mechanistic investigations of AdSV procedures.
Stripping Voltammetry ; Uranium Traces ; Waters ; Chemistry
View record in ScienceDirect (Access to full text may be restricted)