Using experimental design to optimize the surfactant package properties of a metalworking cleaner

presented by Mathijs Uljé

Non-ionic surfactants are an important component of industrial metalworking cleaners. For beverage can manufacturing these cleaners need to deliver good cleaning performance with low foaming properties. These attributes can be strongly influenced by different types of non-ionic surfactants.

Each type of non-ionic surfactant will provide its own property to the cleaning product. Low HLB (Hydrophilic–Lipophilic Balance) surfactants will reduce foaming to a certain degree. Medium HLB surfactants will improve the fluid’s wetting properties. High HLB surfactants will increase cleaning performance together but can also cause an unwanted increased foaming behavior.

With the help of Design-Expert® software an experimental design was set up in the form of an augmented simplex lattice to find an optimal balance between three selected surfactants. The experimental formulations were tested for foaming properties and cleaning performance. All experimental data was analyzed by the software to calculate models with good fit.

The calculated models confirmed that the higher HLB surfactant was responsible for the cleaning performance, but also gave significant foam formation. It also showed that the low HLB surfactant was not needed to reduce the foam, but a certain amount of medium HLB surfactant already gave significant de-foaming properties.

The optimization module within Design-Expert® was used to find the optimal surfactant combination according the set requirements. This optimal product was tested again and showed good results as expected. The use of experimental design and statistical software led to the development of a well-balanced and marketable product within a short period of time.

June 17 at 9:00am Central Time