Metrohm has announced that its 888 Titrando can be used as an Eco titrator that requires only small sample sizes and small volumes of reagents.
The semi- micro titrator has a titration analysis stand that reduces the sample size needed for analysis, the reagent volumes, waste volume and subsequently the running costs for the analysis.
Reagent consumption of 3-4ml is sufficient to determine the content of a sample with a relative standard deviation better than +/- 0.2 per cent.
Sample sizes as low as 25 micro litres are analysed using this method.
Homogeneous solid samples can be weighed directly on a semi-micro balance with an accuracy of 0.01mg.
If an adequate balance is not available or the sample is non-homogeneous the recommended procedure is to produce a stock solution and take aliquots.
Microvalves in the titration system prevent diffusion of reagent at the burette tip and titration modes that wait for an equilibrium to be established gives accurate results, even under non-optimal conditions.
The electrodes recommended with the Eco Titrator are the Metrohm Titrodes, which are a combined electrode for example, Pt or Ag, that do not need a reference electrolyte.
This means that no diaphragm problems are encountered or interference caused by outflowing reference electrolyte.
Smaller Metro sensors also allow the scaling down of almost any titration and some of the combined 'long-life' micro electrodes have been developed for the Eco Titrator.
Smaller volumes allow the use of higher purity solvents, which have lower blank values.
The automatic aspiration and rinsing section of the titrator and the closed system means that when users are dealing with toxic or volatile solvents, a fume cupboard is not necessary.