The new Sci-Q 323 pump: it (helps in finding the age and origin of) rocks!

In the world of Earth Sciences, ultra-pure concentrated acids are needed to separate out elements such as strontium, rubidium, lead and rare earth elements from rocks, prior to the measurement of isotopic ratios for determination of age and origin. These acids generally are purified on site prior to use to remove impurities and stored in FEP Teflon bottles.

Whilst the preparation of pure concentrated acids is a fairly common laboratory application, the Department of Earth Sciences at Cambridge University has been among the first to use the new Sci-Q 323 peristaltic pump from Watson-Marlow, in order to improve safety and efficiency in a process to purify both concentrated nitric and hydrochloric acids.

In the application, the pump delivers acid to a quartz sub-boiling still operating with a constant overflow, requiring a steady measured delivery of acid over an eight hour period. Previously this had been achieved with a simple drip feed from a reservoir, but the operation required close supervision and the regular opening of the fume cupboard to top up the reservoir, with an attendant risk of spillage. Now acid is pumped directly from bulk containers stored within the fume cupboard, requiring far less input from laboratory staff and improving safety.

Dr Hazel Chapman, a research associate at the Department of Earth Sciences first thought of using a peristaltic pump to feed the still after she saw one being used in an inductively coupled plasma application. Dr Chapman said of the pump: "We've been very happy with the way that the new pump works. So far it has proved to be both accurate and reliable, and it is also simple to operate - The large LCD display is very clear and the well spaced out keys are easy to use, even with gloves on."

More information on Sci-Q 300 series pumps.