Ultrasonic with Low-Foam Detergent

Q. We are having foaming issues in an ultrasonic cleaner. Basically, we are looking for a non-foaming version of the Liquinox cleaner we are currently using.  Can you use a detergent that doesn’t foam in an ultrasonic bath?

A. Depending on what the foaming issue is, you may be able to continue using Liquinox® Critical Cleaning Liquid Detergent.  As a general statement, that which makes foam emulsifies well, and that which emulsifies well, works well in ultrasonic cleaning. If the foam is coming from degassing the solution, you may find that if you turn on the tank and de-gas it before you add the Liquinox detergent, you will not have a foaming problem.  

If the foam is coming from a spray rinsing process, then a quick static soak dip in between the ultrasonic cleaning and the spray rinsing can reduce the amount of Liquinox dragout in to the spray rinse process.  This should reduce foaming issues.  

If there is some other foam problem that cannot be avoided, then I would recommend using Solujet® Low-Foaming Phosphate-Free Liquid in the ultrasonic cleaner.  The detergent contains chelating agents that can help remove salts, oxides and other inorganics, as well as emulsifiers and high alkalinity for alkaline hydrolysis of organic residue.

As a final general statement, you can use low foaming detergents for manual cleaning (ultrasonic, scrubbing, soaking) as needed.  The opposite – use of a higher foaming detergent in a washer/high pressure sprayer – is of course not recommended.  It should be noted that low foaming detergents are typically made up of low foaming surfactants,  These are not quite as good at emulsification as the higher foaming ones.  Low foaming detergents therefore will often have higher alkalinity to compensate, therefore allowing them to be efficient and effective.  This high alkalinity should be addressed with appropriate Personal Protective Equipment (PPE) as applicable.

To request these or any Alconox, Inc. detergent for free, please complete the questionnaire at Get Sample. For more information about any one of our Alconox, Inc. detergents, consult the technical bulletin for each product. Or click here to access each of our detergent’s  Safety Data Sheets.

Do you have a critical cleaning question for the experts at Alconox, Inc.?  Search TechNotes to see if it’s been answered before or Ask Alconox.

Contact us any time: cleaning@alconox.com