Patent ID: 6861032

Claim:
A method of using an oxygen scavenger, comprising: adding to boiler water an effective amount of an oxygen scavenger including, as an effective component, a heterocyclic compound with N-substituted amino group, or salt thereof, and at least one of alkaline agent and water soluble polymer, wherein the heterocyclic compound with N-substituted amino group is 1- aminopyrrolidine, 1- amino-4-methylpiperazine, 1-aminopiperidine, 1-aminohomopiperidine, 1,4-diaminopiperazine, or morpholinobyguanide; said salt thereof is water soluble salt of said heterocyclic compounds and aliphatic carboxylic acid selected from the group consisting of succinic acid, glutaric acid, adipic acid, gluconic acid, glycollic acid, lactic acid, malic acid, tartaric acid and citric acid, or polycarboxylic acid including polyacrylic acid; and the alkaline agent is sodium hydroxide, potassium hydroxide, sodium carbonate, or potassium carbonate.