Sulfidation treatment of copper-containing plating sludge towards copper resource recovery.
The present study is concerned with the sulfidation treatment of copper-containing plating sludge towards copper resource recovery by flotation of copper sulfide from treated sludge. The sulfidation treatment was carried out by contacting simulated or real copper plating sludge with Na(2)S solution for a period of 5 min to 24 h. The initial molar ratio of S(2-) to Cu(2+) (S(2-) to Me(2+) in the case of real sludge) was adjusted to 1.00, 1.25 or 1.50, while the solid to liquid ratio was set at 1:50. As a result, it was found that copper compounds were converted to various copper sulfides within the first 5 min. In the case of simulated copper sludge, CuS was identified as the main sulfidation product at the molar ratio of S(2-) to Cu(2+) of 1.00, while Cu(7)S(4) (Roxbyite) was mainly found at the molar ratios of S(2-) to Cu(2+) of 1.50 and 1.25. Based on the measurements of oxidation-reduction potential, the formation of either CuS or Cu(7)S(4) at different S(2-) to Cu(2+) molar ratios was attributed to the changes in the oxidation-reduction potential. By contrast, in the case of sulfidation treatment of real copper sludge, CuS was predominantly formed, irrespective of S(2-) to Me(2+) molar ratio.
Kuchar
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Department of Chemical Engineering, Nagoya University, Furo-cho, Chikusa-ku, 464-8603 Nagoya, Japan.
Fukuta
T
T
Onyango
M S
MS
Matsuda
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H
D003300:Copper / Q000737:chemistry*; D004595:Electroplating; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D010316:Particle Size; D012037:Refuse Disposal / Q000379:methods*; D012722:Sewage / Q000737:chemistry*; D013455:Sulfur / Q000737:chemistry; D013997:Time Factors; D014873:Water Pollutants / Q000302:isolation & purification*; D014961:X-Ray Diffraction
D007220:Industrial Waste; D012722:Sewage; D014873:Water Pollutants; D013455:Sulfur; D003300:Copper; C017846:cupric sulfide