Aqueous acid cleaning, corrosion and stain inhibiting compositions in the vapor phase comprising a blend of nitric and sulfuric acid
AssigneeEcolab USA Inc.
InventorsPaul F. Schacht, Eric V. Schmidt
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Abstract
The present invention relates to sulfuric/nitric blended acid cleaners which employ the use of ethoxylated amines and/or ethoxylated alcohols as a corrosion and stain inhibitor in the vapor phase for cleaning metal and other surfaces, particularly stainless steel. Method of use and manufacturing of the same are also disclosed.
Claims18
A method of inhibiting vapor phase corrosion and staining on a stainless steel surface in a clean in place process, the method comprising:
- (a) applying a vapor phase corrosion inhibited acid cleaning composition to a stainless steel surface, the composition comprising an acid cleaning solution in contact with the stainless steel surface and a vapor phase corrosion inhibitor and up to 4 weight percent urea at a composition temperature range of about 40 degrees Fahrenheit to about 200 degrees Fahrenheit.
A vapor phase corrosion inhibited acid cleaning composition for inhibiting corrosion and staining on a stainless steel surface in a clean in place process, the composition comprising:
- (a) about 0.05 wt. % to about 5 wt. % vapor phase corrosion inhibitor;
- (b) about 5 wt. % to about 50 wt. % nitric acid or about 1 wt. % to about 30 wt. % sulfuric acid or mixtures thereof;
- (c) up to about 4 wt. % urea;
- and
- (d) about 1 wt. % to about 80 wt. % water.
Dependencies are inferred from the claim text.