Know the Facts About Replacement Solvents

Solvents used for cleaning operations vary in chemical nature, physical properties and environmental impact. They also vary in performance efficacy which is contingent on substrates to be cleaned as well as contaminants removal compatibility. Cost is another variation for solvents based on raw materials used in the formula and other criteria.

Recent supply changes in the past two years have drastically affected the future availability of some fluorinated solvents —hydrofluoroethers (HFEs) and hydrofluorocarbons (HFCs). Regulatory actions by the Environmental Protection Agency (EPA) Toxic Substance Control Act (TSCA) to ban or severely restrict the use of other specific solvents have further affected the solvent market. These conditions will mandate solvent users to review their cleaning processes and chemicals to ensure an uninterrupted production workflow.

If change is required, existing solvent users may face challenges in meeting federal, state or local regulatory compliance within the regulated time limits. Most industries requiring precision or critical cleaned parts prefer solvents over an aqueous cleaning process for many reasons. 

Most changes in a manufacturing process require validation and approvals to meet quality levels, PPAP specifications, environmental compliance and other prerequisites. A manufacturer must also consider the cleaning process to meet production and operational cost parameters. All of this takes time and effort to replace specific solvents.

Traditional vapor degreasing solvents are facing increased environmental concerns which may affect solvent cleaning operations. Those currently using solvent cleaning (by choice or necessity based on production requirements), may be affected.

For example, if a company uses 3M Novec 7100, 71DE, 71IPA, 72DE, 72DA, 73DE and other solvents, then it will be affected. 3M has discontinued these products, which are becoming more scarce as well as more costly. And the expiration time limit for availability is passing quickly.

3M officially announced in 2022 that it will exit per- and polyfluoroalkyl substance (PFAS) manufacturing and work to discontinue the use of PFAS in its product portfolio by the end of 2025 with no orders accepted after March 31, 2025. The trade name for this product family is Novec.

Fact vs. fiction

Fiction: 3M will develop new solvents to replace the Novec products before sunset date.

Fact: While any decision to develop new fluorinated solvents remains solely with 3M, there is consensus in the market that this will not occur. There is a defined sunset date by 3M for discontinuation of the Novec products. Review and plan accordingly if using these solvents.

Fiction: There are no existing replacement solvents for a vapor degreaser.

Fact: There are various solvents on the market that can replace PFAS-regulated solvents with an easy transition (drop-in replacement) for modern vapor degreasers. This conversion eliminates new equipment procurement, meets environmental compliance and will decrease the process validation time limit.

Let’s talk about PFAS

Numerous public alerts, scientific studies, news stories and U.S. government environmental actions have focused on this chemical substance’s long-term effects on human health and the environment. These chemicals consist of a variety of fluorinated substances that are used in a multitude of applications.

Fiction: All fluorinated solvents are PFAS materials; therefore, they will be banned from all uses on a national level.

Fact: The EPA has established public documents that define fluorinated substances that are classified as PFAS. Not all fluorinated solvents contain substances listed as PFAS. Individual states are developing definitions for PFAS regulations. Always consult current regulations.

In June 2023, the EPA announced a framework to prevent new or foreign-sourced PFAS from entering the U.S. market without scrutiny.

Other solvents facing regulatory actions

HFC solvents will no longer be acceptable for use per Department of Defense, General Services Administration and National Aeronautics and Space Administration (NASA) guidelines (public notice issued). The American Innovation and Manufacturing (AIM) Act, which went into effect in December 2020, mandates a phasedown schedule of HFC production beginning in 2024, when 40% of HFCs were removed from the marketplace.

EPA TSCA has defined the scope of the risk for commonly used vapor degreasing solvents listed here, and has published a “Chemical Risk Evaluation” for each of the following solvents: trichloroethylene (TCE); perchloroethylene (PERC); 1 bromopropane (nPB); methylene chloride (MC);  and n-Methylpyrrolidone (NMP).

Fiction: All solvents will be banned in the future.

Fact: The EPA and other organizations have recognized the need for solvent cleaning where aqueous or other methods will not work or are not preferred for many reasons. This is why scientific studies and approval for new-generation solvents will continue for many years.

Fiction: There is plenty of time to convert to another solvent.

Fact: There is not much time, in some respects. The confirmed sunset date for some specific solvents is scant months away. If a cleanliness level must meet defined specifications such as medical, aerospace and other critical applications, the selection of a solvent that meets performance and environmental health and safety concerns may require extensive testing/validation/approval.

Fiction: New lower cost and nonregulated solvents will soon be available.

Fact: There are limited acceptable chemical options for solvent cleaning applications. Most industry experts agree the solvent products available on the market today that will meet environmental compliance will be the long-term sustainable option.

Fiction: Cost for solvent cleaning is much higher than an aqueous process.

Fact: The total operational cost for solvent cleaning is actually much lower than an aqueous process for similar production uses. There are many advantages for selecting solvent versus aqueous when all facts are considered: a water-free process, complex geometry is easier to clean due to lower surface tension (penetration), rapid drying with no residue, less process stages, lower energy consumption, cleaning agent can be recycled/reused, reduced waste disposal and process time, multi-metals compatibility, multi-soils compatibility and more.

Action plan

Check any solvents currently being used for vapor degreasing by product name, safety data sheet or chemical abstracts service (CAS) number and verify whether they will be affected.

Thoroughly review any replacement solvent being considered, including all ingredients in the product, purity/quality of the solvent, source of origin, supply availability and any other physical properties that may impact performance and/or environmental compliance.

Do not delay as the life of some solvents expires soon. If not prepared, the overall effect could be severe/costly to your operations.

Contact your local representative to arrange for a courtesy visit to help you plan your conversion in a timely manner to a more environmentally safe process.