Laboratory techniques make regular use of anhydrous solvents, especially in analysis and synthesis. But to purify and dispense them brings many difficulties.

To address this need we have taken further the high purity concept of our famous ROMIL‑SpS^™ Super Purity Solvents. A range of specially dried solvents with such low water levels that surpass even the so-called anhydrous offerings from rivals. In general ROMIL Hi‑Dry^® anhydrous solvents are specially produced to a water specification of less than 50 ppm (<0.0050%). However, many solvents go well beyond that and are routinely produced to lower than 5 ppm (<0.0005%). The water content itself is strictly controlled by coulometric Karl Fischer analysis

Solvents this dry need a packaging system designed to ensure that the exceptional state of dryness achieved at time of purification is retained throughout storage and use. Before filling, we first oven-dry the amber glass bottles to remove all traces of water which may be present on the inner walls. At such low levels even this trace moisture is noticeable. The bottles are then filled under an inert atmosphere of dry nitrogen to prevent moisture build-up and sealed with a special cap.

Specially designed both to retain solvent dryness and purity and to facilitate dispensing, the Hi‑Dry^® cap features a double seal; a PTFE wad and a self-sealing septum. The PTFE wad sits between the solvent and the septum thereby maintaining the original chemical purity and giving an extended shelf life before initial use.

The self-sealing septum allows the solvent to be dispensed by syringe at the point of use. Alternatively, because the cap itself is screw-on it may also be opened conventionally. However, it is important to note that once in contact with the atmosphere product quality can deteriorate depending on the hygroscopic nature of the solvent.

To overcome this we recommend that dispensing operations are conducted under dry nitrogen either in a dry cabinet or with a positive pressure of the gas within the bottle. For safety reasons this should not exceed 0.3 bar (0.31 kg/sq cm) and should only be undertaken by personnel trained in such techniques and wearing appropriate safety equipment.

Choose the pack most suitable for your application out of a wide range of sizes from 100ml to 2½LT. Bulk packaging is available in the form of ROMIL LiQuiSure^™ stainless steel flasks.

Hi‑Dry is a registered trademark of ROMIL Ltd.