Milestone has developed the duoPUR and subPUR, sub-boiling distillation systems which allow laboratories to make their own high purity acids at dramatically reduced costs.
In the preparation of high purity reagents, there is only one significant and practical choice for the method of purification: sub-boiling distillation
US EPA SW-846, Chapter 3, Update IVB.
Why sub-boiling technology?
The chemical reagents used during the analysis are an important source of the analytical blank. Sub-boiling distillation has been demonstrated to be the best method of acid purification. It uses contactless infrared lamps to vaporize the surface liquid at a temperature typically 20°C below the boiling point. In contrast to conventional distillation, where strong boiling action generating aerosolized particles results in contamination of the original liquid with the distillate, a gentle surface evaporation during sub-boiling distillation prevents the formation of spray or droplets and yields to a very high pure acid.
duoPUR Quartz sub-boiling system
The duoPUR consists of two quartz distillation units. Each unit contains two infrared heating elements (1), a water cooled condenser (2), a high-purity PFA collection bottle (3), and a fully automatic acid loading/discharge system. The vaporized liquid is collected on the inclined water-cooled condenser and drips into the collection bottle. The distillation process is microprocessor controlled, allowing the user to set the distillation time and power level by using a compact control terminal with easy-to-read, bright, full-color, touch-screen display. The distillation rate ranges from 50 to 400 mL per hour, depending on the power setting and the temperature of the cooling water.
Read our book! It explains how a laboratory can reach full control of analytical blanks and sample preparation for obtaining accurate results. The application of instruments and strategies to control sample prep blank is often called a “Clean Chemistry” technique. This book discusses the factors impacting blank quality, in particular when microwave digestion is used, and reviews some Clean Chemistry products and technologies designed to help the analyst generate superior analytical data on their ICP-OES or ICP-MS instrumentation.