METHOD OF PRODUCING ANTISEPTIC PREPARATION FOR PROTECTION OF WOOD Russian patent published in 2000 - IPC

FIELD: chemical industry, particularly, production of antiseptic compositions for protection of wood and articles made from wood from decomposition and destruction by termites, fungi and insects. SUBSTANCE: method includes leaching with sulfuric acid of copper-arsenic cakes of copper refining in heating and separation of copper-containing product. The method is distinguished by the fact that copper-arsenic cakes are treated with sulfuric acid with copper-sulfuric acid ratio of 1:(1.0-1.52). After filtration and evaporation, excess of copper sulfate is separated by crystallization at temperature of 5-30 C. Added to mother liquor with arsenic-copper ratio of 1: (0.001-0.2) are compounds of hexavalent chromium and bivalent copper to obtain arsenic-chromium-copper ratio equal 1:(0.6-1.5):(0.3-0.8). In so doing, preliminary aqueous leaching of copper-arsenic cakes is carried out with solid-liquid ratio equal 1:(2-5). EFFECT: simplified process, prolonged protection of wood. 2 cl, 1 tbl, 3 ex