Manufacture of finely divided copper oxychloride or copper oxychloride compositions particularly suitable as plant protecting agents

摘要

Finely divided copper oxychloride is produced by reacting copper oxide at say 10-35 DEG C with concentrated hydrochloric acid or a solution of ferric, zinc, manganous, aluminium or magnesium chloride in amount sufficient to provide 2 grm. atoms Cl per 4 grm. atoms Cu. The copper oxide may be prepared by ignition of metallic copper in air, or by precipitation from a copper salt solution, or copper oxychloride suspension by calcium or sodium hydroxide. According to an example the oxychloride suspension is prepared by dissolving metallic copper in cupric chloride solution into which air is bubbled. Direct steam heat may be used in the dissolution process. The rinsed oxychloride precipitate is diluted and treated with 20-30 per cent caustic soda solution at 60-80 DEG C. The copper oxide produced is washed until chloride-free. A slight excess thereof is preferably used in its conversion to oxychloride. The Specification as open to inspection under Sect. 91 is not limited to the use of the chlorides specified above, cupric, nickel and stannous chlorides being also mentioned. This subject-matter does not appear in the Specification as accepted.