Behavior of Nickel as a Trace Element and Time-Dependent Formation of Spinels in WEEE Smelting
For better understanding and maximal value utilization of the WEEE smelting process, the behavior and distribution of different trace elements must be known. In this study, the behavior of nickel as a trace element was studied in an equilibrium system with metallic copper—spinel saturated iron silicate slag (with 3 wt-% K2O)—iron aluminous spinel—gas. The experiments were conducted in alumina crucibles at 1300 °C, in oxygen pressure range of 10−10–10−5 atm. A time series of 15–60 min experiments was also conducted for investigating the formation rate of the primary spinel phase in the system. The results show that the distribution coefficient of nickel between metallic copper and liquid slag changes from approximately 70 to 0.4 along the increasing oxygen pressure range. In addition, a significant part of the nickel deports into the spinel phase. The spinel formation was investigated based on composition analysis results and visual observations from SEM-images.
KeywordsDistribution Slag Potassium oxide Copper smelting
The scholarship from the Finnish Steel and Metal Producer’s Fund (LK) has enabled this work. The assistance of Mr. Lassi Pakkanen at Geological Survey of Finland regarding the EPMA analyses is greatly appreciated.
- 2.Wood J et al (2011) Secondary copper processing using outotec ausmelt TSL technology. Presented at the AusIMM’s MetPlant conference, PerthGoogle Scholar
- 4.Anand S, Kanta Rao P, Jena PK (1980) Leaching behaviour of copper converter slag in sulphuric acid. Trans Inst Min Metall 33:77–81Google Scholar
- 5.Jones RT, Hayman DA, Denton GM (1996) Recovery of cobalt, nickel, and copper from slags, using DC-Arc furnace technology. Presented at the 35th annual conference of metallurgists, Canada, Mintek paper no. 8360Google Scholar
- 7.Hagelüken C (2006) Recycling of electronic scrap at Umicore’s integrated metals smelter and refinery. World Metall-ERZMETALL 59(3):152–161Google Scholar
- 8.Avarmaa K, O’Brien H, Taskinen P (2016) Equilibria of gold and silver between molten copper and FeOx–SiO2–Al2O3 slag in WEEE smelting at 1300 °C. In: Proceedings of the 10th international conference on molten slags, fluxes and salts MOLTEN, USA, pp 193–202Google Scholar
- 10.Klemettinen L, Avarmaa K, Taskinen P (2017) Trace element distribution is black copper smelting. World Metall-ERZMETALL 70(5):257–264Google Scholar
- 15.London metal exchange, 3-month average prices. https://www.lme.com/Metals. Accessed 25 Jan 2018
- 19.Sukhomlinov D, Taskinen P (2017) Distribution of Ni, Co, Ag, Au, Pt, Pd between copper metal and silica saturated iron silicate slag. In: Proceedings of the European metallurgical conference EMC, Germany, vol 3, pp 1029–1038Google Scholar
- 22.Pouchou JL, Pichoir F (1986) Basic expression of “PAP” computation for quantitative EPMA. In: 11th international congress on X-ray optics and microanalysis ICXOM, Canada, pp 249–256Google Scholar