Brand Dispensette S Trace Analysis bottle-top dispenser, Analog, 1-10 ml, Tantalum Spring, with Recirculation Valve, DE-M, 4640241

When high-purity acids are dispensed for trace element determination, every millilitre that does not have to be discarded counts. The Dispensette S Trace Analysis with recirculation valve returns excess reagent to the stock bottle and replaces the platinum-iridium of the standard version with a tantalum valve spring that introduces no traces of precious metal into the sample. This makes the device of interest for ICP analysis and for sample preparation where traces of metal would distort the measurement.

Recirculation function

This version has a recirculation valve with a recirculation tube. Excess reagent can thus be returned to the stock bottle, which saves cost with high-purity trace analysis reagents because less substance has to be discarded.

Mounting and cleaning

Mounting is the same as for the standard Dispensette S: screw on the bottle adapter, shorten the telescopic filling tube to the bottle height, vent the system several times. The mounting key from the scope of delivery is needed to change the valve spring, should the platinum-iridium version be required later after all. Because the device must not be autoclaved, it is cleaned by rinsing with a suitable solvent instead of steam sterilisation. The bottle adapters supplied (GL28/S28, GL32, GL38, S40) cover the bottle sizes common in trace analysis, an additional GL24-25 adapter as in the standard series is not part of the scope of delivery for this version.

Distinction within the Trace Analysis series

Within the Dispensette S Trace Analysis series, only the valve spring (platinum-iridium or tantalum) and the recirculation valve option differ, accuracy and volume range are identical for both valve spring variants. Compared with the standard Dispensette S in red, the difference lies in the choice of materials for trace analysis, not in the dispensing technology itself. Anyone who does not carry out trace analysis that is sensitive to precious metals or tantalum is adequately served by the regular Dispensette S Digital or Fix in red and saves money compared with the Trace Analysis version. For applications where hydrofluoric acid or sodium hydroxide solution 30 % must be dispensed, the platinum-iridium variant 4640040 or 4640041 is the more suitable choice, but it is outside our current range.

Accuracy and graduation

The volume range is 1 to 10 ml, the graduation 0.2 ml. Accuracy and coefficient of variation are stated as 0.5 %/50 µl and 0.1 %/10 µl respectively. The scale on the analog cylinder is set by hand, there is no digital counter on this version. These values apply across the whole setting range and are independent of which valve spring is fitted.

Tantalum valve spring

With the tantalum spring, hydrogen peroxide is additionally permitted, whereas the platinum-iridium variant is not suitable for it, but allows hydrofluoric acid and sodium hydroxide solution 30 % instead. Both valve spring variants tolerate, among others, hydrochloric acid, nitric acid, sulphuric acid, phosphoric acid, perchloric acid, ammonia solution, acetic acid, water and bromine. Neither is suitable for organic solvents, trifluoroacetic acid, explosive liquids and suspensions. According to the operating instructions, the device must not be autoclaved. The wetted parts consist of fluoroplastics (ETFE, FEP, PFA, PCTFE, PTFE) and an Al2O3 sapphire element, the same material basis as the standard Dispensette S, only without the borosilicate glass components.

Frequently asked questions

Why no platinum-iridium spring in this item?
The tantalum version is additionally suitable for hydrogen peroxide, whereas platinum-iridium is not suitable for it. Hydrofluoric acid and sodium hydroxide solution 30 % are permitted only with platinum-iridium. Which valve spring fits therefore depends on the reagents actually dispensed.

Is the Trace Analysis version autoclavable?
No, according to the operating instructions the device must not be autoclaved, unlike the standard Dispensette S in red.

Typical applications

• Sample preparation for ICP-MS and ICP-OES trace analysis
• Reagent addition in trace element determinations without precious metal contamination
• Dispensing of high-purity acids in inorganic trace analysis

Technical details

Scope of delivery

• Bottle-top dispenser
• Telescopic filling tube
• Discharge tube including recirculation tube
• Mounting key
• Bottle adapters (GL28/S28, GL32, GL38, S40)
• Quality certificate
• Operating instructions

Individual requirements and procurement service

For the platinum-iridium version of the Trace Analysis series or additional accessories, we provide support through our own procurement service.