Looking for a viable alternative to fluorinated solvents in parts cleaning?

Increasing regulatory pressure on PFAS could impact use of fluorinated solvents

Due to acceleratory global regulatory pressure on PFAS (per- and polyfluoroalkyl substances), many hydrofluoroethers (HFEs) and hydrofluoroolefins (HFOs) which fall under the definition of PFAS are now facing an uncertain future. Their use as fluorinated solvents in industrial parts cleaning could be restricted or prohibited.

Many manufacturing companies are currently seeking variations of HFEs and HFOs which are PFAS-free to use as drop-in replacements in open degreaser. It is understandable because direct drop-in replacements can keep the operations running with minimal disruptions. But there is a much more important and far-reaching question for companies to consider: will drop-in replacements used in open and semi-open (normal atmospheric) equipment also make for a future-proofing cleaning approach – especially when viewed within the context of increasing regulatory requirements on health, safety and environmental protection?

Not to forget that many fluorinated solvents are often blended with Trans-1,2 dichloroethylene (t-DCE) – and t-DCE is under legislative pressure itself.

Modified alcohols as a viable future-proof cleaning solution

A viable cleaning solution should not only deliver quality cleaning results, but also enable cost efficiency, safety and sustainability. One such solution is modified alcohol.

Our modified alcohol solvents – DOWCLENE™* 16-Series as well as DUALENE™ 1601 S – are chlorine-free, bromine-free and fluorine-free. Produced synthetically, modified alcohols are remarkably stable in temperature and pH. With both non-polar and polar properties, they can effectively clean off non-polar contaminants such as oils and greases, just as effectively as certain polar contaminations like cooling emulsions or solids such as particles and abrasives.

Modified alcohols have a flashpoint and therefore must be applied in vacuum closed cleaning machines, or the so-called airtight/airless degreasers. Users currently operating open/semi-open equipment are likely to see the initial equipment expenditure as a hurdle. They might also be apprehensive about changing their cleaning process altogether.

However, compared to the high consumption of fluorinated solvents (PFAS-free or not) and their running costs due to emissions and drag out losses, a closed cleaning machine can practically pay itself back due to the many cost savings it enables – in addition to increased process safety and minimized environmental impact.

A closed vacuum cleaning machine can offer manifold advantages on cost, process stability and environmental protection:

Cost efficiency

• Solvents used in closed machines are much cheaper than fluorinated products
• Solvent can be recycled and reused much more efficiently thanks to built-in vacuum distillation unit
• Solvent lifespan can be further expanded by stabilizers, resulting in less consumption and fewer bath exchanges
• Solvent in waste stream is minimized due to efficient recycling with vacuum distillation
• Working chamber opens following vacuum drying – no solvent residues left on parts
• The capability of modified alcohols to process both polar and non-polar contamination may reduce the need for additional cleaning processes

Process security

• Solvent condition can be regularly monitored on-site using simple test kits
• Reliable good cleaning result
  » High solvent quality in rinsing step enables required level of cleanliness
  » Efficient vapor degreasing as last cleaning step thanks to high temperature difference between parts and vapor
• Vacuum drying ensures that risk of solvent being trapped in blind holes/small crevices is minimized even when rotation isn’t used

Environmental protection

• Virtually no air emissions – a cost, environmental and safety benefit
• Hermetically sealed construction means there is minimal risk of contaminating ground water
• Operators have virtually no contact with the chemical
• Safety containers such as the SAFE-TAINER™ System further ensures emission-free and spill-free transfer of solvent

Adopt a long-term view when assessing the best technical option
Changing your cleaning process from an open to a closed machine can take time and efforts. Technical consultation, testing and verification are particularly vital in the solution finding process.

Users of fluorinated solvents which fall under the PFAS definition are now offered an opportunity to re-assess their current cleaning set-up and exploit alternative options which might bring even greater benefits in terms of cleaning performance, cost savings and sustainability standards in the long run.

Direct replacement can be an option, but it must not be the only one. Companies are well advised to keep an open mind, explore and test until they settle on a technical solution that will not only serve them well today, but also in the years to come. 

For more background information on PFAS and how it might impact use of fluorinated solvents in parts cleaning, please refer to this document: https://insights.safechem.com/pfas_background_flyer

™ Trademark of SAFECHEM
™* Trademark of The Dow Chemical Company