Zur Korrosion von Kupferwerkstoffen in Tetrachlorkohlenstoff

Corrosion of copper base materials in carbon tetrachloride Copper (OFHC), two copper zinc alloys (CuZn36 and CuZn15), one nickel-copper alloy (NiCu30Fe), the copper tin casting alloy G-CuSn10, and the copper aluminium casting alloy G-CuAl10Fe were immersed in the following boiling media: carbon tetrachloride dried over P₄O₁₀, carbon tetrachlorid saturated with water and two phase mixtures of carbon tetrachloride and water. The individual samples were positioned within the organic phase, within the aqueous phase, within the vapour phase and within the condensated phase, respectively. OFHC copper, NiCu30Fe, CuZn15 and G-CuAl10Fe are corrosion resistant (corrosion rate ≤ 0,01 mm/y) in dry as well as in water saturated CCl₄. The same statement is valid for alloys CuZn36 and G-CuSn10 which show a corrosion rate of approximately 0,02 mm/y within the condensate of CCl₄ saturated with water. All alloys exhibit more or less corrosion within the two phase mixtures. Within the aqueous phase the materials do not prove to be resistant: they are completely dissolved in less than 30 days. Paralle to the corrosion of CuZn36 and G-CuAl10Fe zinc and aluminium, respectively, went into solution. The vapour phase above the carbon tetrachloride-water mixture consisted of over 90% by volume carbon monoxide. This prove that the corrosion of all materials which had been immersed in the aqueous phase was effected by phosgene.