Voltammetric titration

In voltammetric titration the reaction is pursued by means of voltammetry interest is sometimes taken in the complete titration curve, but mostly in its part around the equivalence point in order to establish the titration end-point. 

In a wider sense the subject of voltammetric titration would include the polarographic mode as a type of amperometric titration however, we have already treated this in Section 3.3.1.3, because we prefer to use the term voltammetric titration in the strict sense, i.e., for faradaic non-polarographic titration techniques, a survey of which is given in Table 3.3. 

As titrations require rapid and complete chemical reactions, it is mandatory to work under hydrodynamic conditions hence, with stationary electrodes, which are often used in voltammetric titrations, the solution is stirred by a mechanical or magnetic stirrer with rotating electrodes an additional stirring may sometimes be superfluous. 

Fig. 3.71 offers an instructive possibility for considering the voltammetric titration techniques mentioned in Table 3.3, and we shall do so in the sequence given there. 

Accessories are available for some instruments to enable photometric or voltammetric titrations (e.g. the Karl-Fischer determination of water) to be performed. Others allow the direct transfer of weighings from an electronic balance into RAM where they can be used in the computation of results. 

G. Scarponi, G. Capodaglio, C. Barbante, P. Cescon, The anodic stripping voltammetric titration procedure for study of trace metal complexation in sea water, in Element Speciation in Bioinorganic Chemistry, S. Caroli (Ed.) Wiley New York, 1996, 363-418. 

Electroanalytical methods are frequently applied to the study of metal complexa-tion by organic ligands in particular, two voltammetric titration methodologies to study trace metal complexation in sea water have been developed. In both cases... 

The procedure for studying metal complexation in sea water includes both the determination of the total content in an aliquot of the sample subjected to acid digestion using the procedure reported above, and the voltammetric titration of organic ligands in an untreated aliquot of the sample with the metal of interest (samples destined for speciation measurements are not subject to acidification or... 

Ascorbic acid content determined in kiwi fruit samples by means of HPLC with UV detection and voltammetric titration. 

Potentiometric and voltammetric titrations and assumed 1 1 metal/fulvate mole ratio in the complex. ... 

Device for carrying out voltammetric titrations with adjustable current strength. 

Another important practical result from these speciation studies with NTA and EDTA is a new very sensitive voltammetric procedure for the simultaneous determination of both ligands, down to trace levels in natural water[75]. The method is based on a voltammetric titration with Bi(III). 

In the voltammetric titration technique a cell is set up consisting of an electrode responsive to the substance being titrated (but not to the added reagent) and a reference electrode the solution contains a large excess of an indifferent electrolyte (q.v.). 

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