Patent Number: 6,254,801

Title: Hardness-stabilizing percarboxylic acid solutions, a process for their preparation and their use

Abstract: Hardness-stabilizing and scale-preventing aqueous percarboxylic acid solutions contain a hardness stabilizer selected from the group (i) polymers prepared by oxidative polymerization of acrolein or of acrolein and acrylic acid, (ii) polyacrylic acid, (iii) copolymers of acrylic acid and another unsaturated carboxylic acid and (iv) polymaleic acid, wherein the average molecular weight M.sub.w of the hardness stabilizer is in the range 500 to 25000, and the solutions are obtained by adding the hardness stabilizer to a percarboxylic acid solution. Preferred solutions contain a hardness stabilizer (i) with a M.sub.w of 1000 to 15000. The solutions may also contain a surfactant. The solution can be used for controlling microorganisms in aqueous systems, in particular water-circulating systems.

Inventors: Reinold; Andreas (Grundau, DE), Walzer; Egon (Maintal, DE)

Assignee: Degussa AG

International Classification: A01N 37/16 (20060101); C02F 1/50 (20060101); C07C 407/00 (20060101); C02F 1/72 (20060101); C02F 5/08 (20060101); C01B 015/00 (); C01B 015/055 ()

Expiration Date: 07/03/2018