PTFE sub-boiling distillation system

The Milestone subCLEAN is a compact and easy-to-use sub-boiling system suitable for the purification of HF, as well as for HNO3 and HCl.

Make your own HF, HNO3 and HCl acids

The chemical reagents used during the analysis are an important source of the analytical blank. Sub-boiling distillation systems has been demonstrated to be the the leading method of acid purification.
In contrast to acid purification through conventional distillation, where strong boiling action generating aerosolized particles results in contamination of the original liquid with the distillate, acid distillation system using sub-boiling technology prevents the formation of spray or droplets and yields to a very high pure acid.
The Milestone subCLEAN is a compact and easy-to-use sub-boiling system, where all parts in contact with acids are made of high-purity fluoropolymers. Offering an optimal purification method for preparation of high purity reagents, our subCLEAN system is therefore suitable for HF, as well as for HNO3 and hydrochloric acid purification.

  • ● Up to 90% cost saving of ultrapure acids
  • ● High productivity
  • ● ‘On-demand’ acid purification
  • ● Re-purification of contaminated acids

Product Specialist

Mikael Alfredsson

"Our expert in Digestion, Extraction, Syntesis and Evaporation with more than 20 years experience in the field of sales and service. Contact me for if you have questions or need a quotation"

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031-709 8186

“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?

With subCLEAN system, the acid is automatically loaded into the distillation container, where it is gently heated below its boiling temperature. All process is microprocessor controlled by using a compact control terminal with easy-to-read, bright, full-color, touch-screen display.
The subCLEAN does not require cooling water or a chiller, as acid vapors rapidly condense into a collection bottle

Compare acid steam cleaning to acid leaching

The container to be cleaned is placed over a PTFE coated glass rod. Acid in the lower reservoir is heated, and purified acid vapor travels up through the glass rod and condenses on the container, removing surface contamination. This method of cleaning is a preferred alternative to the soaking preconditioning methods for the following reasons:

1, The trace metal contamination found in the reagent grade acid remains in the lower reservoir and does not come in contact with the component to be cleaned.
2. The clean component does not remain in contact with the cleaning acid after the surface contamination is removed.
3. The critical surfaces of the clean component are dry when the cleaning process is complete. This eliminates the need for rinsing and air drying.
4. The cleaning process takes place in a sealed container which minimizes airborne contamination and provides a clean environment for the components to be stored until they are needed.

How Much Will Sub-Boiling Distillation Save You Each Month? by forced air cooling.

Do you know how to reduce the sample prep blank?

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.


At Kovalent we strive to establish and develop long-term partnerships with our customers. When we use the word “partnership” we mean that Kovalent becomes an integral part of our customers’ projects, where we are expected to fully understand their application needs. We aim to make Kovalent our customers’ first and natural choice, and this ambition permeates our entire organisation from initial contact to finished and delivered product.


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Phone: +46(0)31-709 81 80
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Genetec is a member of the same family of companies as Kovalent. Both companies share the same set of values and are in many ways integrated with each other. The main difference between the two companies are their products. Kovalent is involved in system solutions including instrumentation and Genetec is mainly working with consumables. The focus of Genetec is chromatography accessories. You are welcome to visit their state of the art web shop: