<p>Traditionally, rolling mills use emulsions based on a mixture of oil and water for lubrication. Since two years ago SAPA has been using (instead of oil) a synthetic lubricant so called conditional emulsion for hot-rolling of aluminum. This lubricant is water based and homogenous at ambient temperature, but switches to a two-phase system at heating above the cloud point.</p><p>This project aims to validate and if necessary modify an existing HPLC method for quantifying two out of three key components (A, B and C) in the conditional emulsion. Attempts to develop a method to quantify the pH adjusting components, X and Y were also made. These two methods are required to optimize the lubricant.</p><p>Due to the complexity of the components, it has been difficult to present a method for quantification, and HPLC with ELS detection was chosen after a long series of trials. Due to a few uncontrollable parameters the proposed analysis method has tendencies to be unstable. The column used is sensitive to changes in equilibrium and ELSD is also less sensitive and less reproducible than the commonly used UV-detector.</p><p>While the proposed assay method shows somewhat large relative standard deviations the method has been shown to produce sufficiently precise and accurate data for the intended purpose.</p><p>Development of a method for the pH-adjusting components X and Y was more difficult than expected. For some reason their difference in chemical properties does not show satisfying impact in the chromatograms.</p><p>This method is still in its cradle and needs further development.</p><p> </p>

Traditionally, rolling mills use emulsions based on a mixture of oil and water for lubrication. Since two years ago SAPA has been using (instead of oil) a synthetic lubricant so called conditional emulsion for hot-rolling of aluminum. This lubricant is water based and homogenous at ambient temperature, but switches to a two-phase system at heating above the cloud point. This project aims to validate and if necessary modify an existing HPLC method for quantifying two out of three key components (A, B and C) in the conditional emulsion. Attempts to develop a method to quantify the pH adjusting components, X and Y were also made. These two methods are required to optimize the lubricant. Due to the complexity of the components, it has been difficult to present a method for quantification, and HPLC with ELS detection was chosen after a long series of trials. Due to a few uncontrollable parameters the proposed analysis method has tendencies to be unstable. The column used is sensitive to changes in equilibrium and ELSD is also less sensitive and less reproducible than the commonly used UV-detector. While the proposed assay method shows somewhat large relative standard deviations the method has been shown to produce sufficiently precise and accurate data for the intended purpose. Development of a method for the pH-adjusting components X and Y was more difficult than expected. For some reason their difference in chemical properties does not show satisfying impact in the chromatograms. This method is still in its cradle and needs further development.