Method of removing dioxane from phosphate ester surfactants
AssigneeGAF Corporation
InventorsMichael M. Katz, Mohamed M. Hashem, Charles P. Talley
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Abstract
Dioxane contaminant is removed from a phosphate ester surfactant having a chain of repeating ethyleneoxy units and containing residual phosphoric acid by means of a process which involves mixing the phosphate ester surfactant with a sufficient quantity of a neutralization agent of substantially completely neutralize residual phosphoric acid contained in said surfactant, and then separating dioxane from said phosphate ester surfactant until the dioxane level is below about 10 ppm. The neutralization agent can be a base such as sodium hydroxide.
Claims12
The method of removing dioxane contaminant from a phosphate ester surfactant have a chain of repeating ethyleneoxy units and containing residual phosphoric acid, comprising the steps of:
- (a) mixing the phosphate ester surfactant with a sufficient quantity of a neutralization agent to substantially completely neutralize residual phosphoric acid contained in said surfactant, and
- (b) separating dioxane from said phosphate ester surfactant until the dioxane level is below about 10 ppm.
Dependencies are inferred from the claim text.