Abstract: A method for producing finely divided stable cupric hydroxide composition of low bulk density comprising contacting solutions of an alkali metal carbonate or bicarbonate and a copper salt, precipitating a basic copper carbonate--basic copper sulfate to a minimum pH in the range of greater than 5 to about 6, contacting the precipitate with an alkali metal hydroxide and converting basic copper sulfate to cupric hydroxide, within the pH range of 7 to 11.

Abstract: Basic copper salts such as cupric hydroxide, basic copper chloride, basic copper sulfate and the like with an alkanolamine result in an unexpectedly beneficial composition useful in a method for treating bodies of water to arrest or eliminate the growth of algae and aquatic weeds; a more stable and less corrosive solution is obtained for storage purposes when the insoluble basic copper salts are reacted with an alkanolamine such as trialkanolamine or mixtures or tri- and dialkanolamines to produce a water soluble copper complex of the organic compounds; moreover, the formed complex of the insoluble basic salts provides a higher copper content in the solution formed by the complex when compared to the acid, water soluble copper salts; full effectiveness of the complex has been observed for extended period of time without decrease of soluble copper content.

Abstract: A method for producing finely divided stable cupric hydroxide comprising contacting solutions of an alkali metal carbonate or bicarbonate and a copper salt, precipitating a copper carbonate, contacting the precipitate with an alkali metal hydroxide and converting the copper carbonate to cupric hydroxide and re-forming alkali metal carbonate and repeating the sequence of additions of copper salt and alkali hydroxide for up to 20 cycles without addition of any additional alkali metal carbonate or bicarbonate.