TN922 : Feseabilty of recovery and selective separation of copper and zinc from an oxide ore sample by acidic leaching and solvent extraction
Thesis > Central Library of Shahrood University > Mining, Petroleum & Geophysics Engineering > MSc > 2019
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Abstarct: Copper and zinc are as the most important non-ferrous mextals and play a significant role in the commercial-industrial different fields. In recent years, the increasing demand for mextals has led to the rapid reduction of primary resources and high-grade ores and consequently the low grade ores, tailings and secondary resources have regarded as a mextal significant source. Hence, this research was focused in the work phases including the leaching behavior of zinc and copper from a tailings sample of porcelain stone and then their recovery from leach solution using solvent extraction process. In first phase, the main and interactive effects of five important factors such as liquid/solid ratio, sulfuric acid concentration, agitation speed, temperature and leaching time were examined on the leaching rate of copper and zinc using response surface methodology. The results indicated that the leaching process was strongly influenced by the interactive effects between factors. Also, the leaching recoveries increased by increasing all factors in the range studied. However, the recoveries were nearly independent of the agitation rate, indicating surface chemical reaction as the leaching kinetics controlling step. The highest leaching recoveries of copper (73.95%) and zinc (81.02%) were obtained under condition of the acid concentration of 10%, 300rpm agitation rate, 10mL/g liquid/solid ratio, 35°C temperature and 75 minutes leaching time. In second phase, the extraction behavior of copper and zinc from sulfate leach solution obtained from the tailings sample of porcelain stone was investigated using Chemorex CP-150 and D2EHPA diluted in kerosene. Chemorex CP-150 demonstrated the higher ability and selectivity for extraction of copper, while D2EHPA had the greater capability for extraction of zinc. About 97.88% copper and 78.2% zinc were extracted at 10 minutes contact time, 1:1 aqueous/organic ratio, 10% (v/v) extractant concentration and ambient temperature respectively with Chemorex and D2EHPA at pH of 2.5 and 2. Meanwhile, McCabe-Thiele diagram was drawn and that it was needed one single-step extraction for copper and a two-stage process for zinc to achieve the highest extraction efficiency. Additionally, the mechanism of extraction process was studied in detail and the findings demonstrated the association of ~1.5 and 1 mole of Chemorex CP-150 and D2EHPA for the extraction of one mole of Cu and Zn from leach solution. Meanwhile, thermodynamic parameters were obtained, indicating that the extraction process was endothermic for copper and exothermic for zinc.
Keywords:
#Porcelain stone tailings sample #Copper and zinc recovery #Leaching #Solvent extraction #McCabe-Thiele diagram
Keeping place: Central Library of Shahrood University
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Keeping place: Central Library of Shahrood University
Visitor: