Process for separating copper from spent solutions forming cuprous-aluminium tetrahalide complexes

摘要

This invention relates to a process for separating copper from spent solutions forming cuprous-aluminium tetrahalide complexes, the said procedure comprising: (1) mixing the said spent solution with at least 0.5 and preferably between approximately 0.5 and approximately 3, more preferably between approximately 0.95 and approximately 1.05 parts by weight of water for each part by weight of the said solution, thus forming a solid precipitate of cuprous halide, an organic phase and an aqueous phase, (2a) contacting the mixture from stage 1, while stirring, with a suitable quantity of a suitable oxidising agent for sufficient time to convert the cuprous halide which is insoluble in water into a water-soluble cupric halide and separating the organic phase and the aqueous phase, or alternatively (2b) separating the organic phase and the aqueous phase and placing the aqueous phase containing the insoluble cuprous halide, while stirring, with a suitable quantity of a suitable oxidising agent for a sufficient length of time to convert the cuprous halide which is insoluble in water into water-soluble cupric halide, (3) placing the aqueous phase containing the dissolved cupric halide in contact with an acceptable metal from the environmental point of view located in a position higher than copper in the electrochemical series, thus precipitating metallic copper, and (4) collecting the precipitated metallic copper by suitable means. In a preferred process for recovering copper from spent solutions forming cuprous-aluminium tetrahalide complexes the process comprises: (1) mixing the said solution with at least 0.5 and preferably between approximately 0.5 and approximately 3, and more preferably between approximately 0.95 and approximately 1.05 parts by weight of a 1 molar, preferably 1 molar to 2 molar aqueous solution of a non- oxidising acid for each part by weight of the said solution forming complexes, thus forming an aqueous phase which contains the cuprous halide and an organic phase, (2) separating the organic phase and the aqueous phase, (3) placing the aqueous phase containing the dissolved cuprous halide in contact with an acceptable metal from the environmental point of view which occupies a higher position than copper in the electrochemical series, thus precipitating metallic copper, and (4) recovering the precipitated metallic copper by suitable means.