Sulfamic acid （SA）, which possesses a zwitterionic structure, was applied as a leaching reagent for the first time for extracting copper from copper oxide ore. The effects of reaction time, temperature, particle siz...Sulfamic acid （SA）, which possesses a zwitterionic structure, was applied as a leaching reagent for the first time for extracting copper from copper oxide ore. The effects of reaction time, temperature, particle size, reagent concentration, and stirring speed on this leach- ing were studied. The dissolution kinetics of malachite was illustrated with a three-dimensional diffusion model. A novel leaching effect of SA on malachite was eventually demonstrated. The leaching rate increased with decreasing particle size and increasing concentration, reac- tion temperature and stirring speed. The activation energy for SA leaching malachite was 33.23 kJ/mol. Furthermore, the effectiveness of SA as a new reagent for extracting copper from copper oxide ore was confirmed by experiment. This approach may provide a solution suitable for subsequent electrowinning. In addition, results reported herein may provide basic data that enable the leaching of other carbonate miner- als of copper, zinc, cobalt and so on in an SA system.展开更多
The effects of BaCl2 on the flotation of K-feldspar using dodecyl amine chloride as the collector under natural pH wereinvestigated by flotation tests, absorption measurements, Fourier transform infrared spectroscopy ...The effects of BaCl2 on the flotation of K-feldspar using dodecyl amine chloride as the collector under natural pH wereinvestigated by flotation tests, absorption measurements, Fourier transform infrared spectroscopy （FTIR） and X-ray photoelectronspectroscopy （XPS）. The results indicated that lower BaCl2 concentration can increase the floatability of K-feldspar, whereas higherBaCl2 concentration can significantly inhibit the flotation of K-feldspar. Peaks at 3548.18, 3475.56 and 3414.35 cm？1in the FTIRspectra of K-feldspar adsorbed by dodecyl amine chloride revealed three forms of -OH. XPS analyses of K-feldspar adsorbed byBa2＋ showed that the concentration of K atom was reduced by nearly twice as those of Si, Al, and O. The activation of BaCl2 at a lowconcentration was mainly caused by Ba2＋ in the form of the ion exchange between K＋ and Ba2＋. The inhibitory action of BaCl2 at ahigh concentration is mainly attributed to the physical absorption of Ba2＋ on the surface of K-feldspar and the fact that a highconcentration of Cl？ causes the chemical equilibrium of dodecyl amine chloride to be changed, and the dodecyl amine chloride in theform of RNH2H＋ is reduced.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 51168020, 51404119, and 51464029)the Natural Science Foundation of Yunnan Province, China (No. 2014Y0845)the Excellent Doctoral Dissertation and Talent Cultivation Foundation of Kunming University of Science and Technology (Nos. 41118011 and 201421066)
文摘Sulfamic acid （SA）, which possesses a zwitterionic structure, was applied as a leaching reagent for the first time for extracting copper from copper oxide ore. The effects of reaction time, temperature, particle size, reagent concentration, and stirring speed on this leach- ing were studied. The dissolution kinetics of malachite was illustrated with a three-dimensional diffusion model. A novel leaching effect of SA on malachite was eventually demonstrated. The leaching rate increased with decreasing particle size and increasing concentration, reac- tion temperature and stirring speed. The activation energy for SA leaching malachite was 33.23 kJ/mol. Furthermore, the effectiveness of SA as a new reagent for extracting copper from copper oxide ore was confirmed by experiment. This approach may provide a solution suitable for subsequent electrowinning. In addition, results reported herein may provide basic data that enable the leaching of other carbonate miner- als of copper, zinc, cobalt and so on in an SA system.
基金Project(51764021)supported by the Key Program of the National Natural Science Foundation of China
文摘The effects of BaCl2 on the flotation of K-feldspar using dodecyl amine chloride as the collector under natural pH wereinvestigated by flotation tests, absorption measurements, Fourier transform infrared spectroscopy （FTIR） and X-ray photoelectronspectroscopy （XPS）. The results indicated that lower BaCl2 concentration can increase the floatability of K-feldspar, whereas higherBaCl2 concentration can significantly inhibit the flotation of K-feldspar. Peaks at 3548.18, 3475.56 and 3414.35 cm？1in the FTIRspectra of K-feldspar adsorbed by dodecyl amine chloride revealed three forms of -OH. XPS analyses of K-feldspar adsorbed byBa2＋ showed that the concentration of K atom was reduced by nearly twice as those of Si, Al, and O. The activation of BaCl2 at a lowconcentration was mainly caused by Ba2＋ in the form of the ion exchange between K＋ and Ba2＋. The inhibitory action of BaCl2 at ahigh concentration is mainly attributed to the physical absorption of Ba2＋ on the surface of K-feldspar and the fact that a highconcentration of Cl？ causes the chemical equilibrium of dodecyl amine chloride to be changed, and the dodecyl amine chloride in theform of RNH2H＋ is reduced.
