Effect of Power and Exposure Time on the Microwave-Assisted Roasting of Refractory Gold Ore

Abstract:

Reserves of high-grade gold ore worldwide are decreasing, and some industries have started processing refractory gold ore. Refractory gold ore contains sulfide minerals such as pyrite (FeS₂), chalcopyrite (CuFeS₂), galena (PbS), and sphalerite (ZnS). Gold in refractory ores occurs as fine-size gold-bearing sulfide minerals. In this study, the microwave-assisted roasting method has been investigated as a pretreatment for a refractory gold ore. This method can provide rapid heating radiation, cause micro-cracks, and trigger the decomposition of sulfide minerals. The presence of additive helps in the oxidation of sulfide minerals. The microwave-assisted roasting was carried out using variations in microwave power and time. Microwave power between 300 - 600 watts significantly affected the increase in roasting temperature and weight loss of refractory gold ore. The highest temperature reached 567°C in roasting at 800 watts for 30 minutes. The optimum condition for microwave roasting was achieved at 400 watts of power with a roasting time of 30 minutes. Metals extraction of Cu, Zn, Pb, and Fe reached 97.2%, 82.7%, 16.1%, and 2.1% in water leaching.

• Periodical: Materials Science Forum (Volume 1113)
• Pages: 111-117
• DOI: https://doi.org/10.4028/p-L8NrjW
• Online since: February 2024
• Authors: Abdul Hapid*, Siti Zullaikah, Mahfud Mahfud, Adji Kawigraha
• Keywords: Microwave for Gold Processing, Microwave Roasting, Refractory Gold Ore, Sulfide Mineral

References

[1] S. H. Farjana, N. Huda, and M. A. P. Mahmud, "Life cycle analysis of copper-gold-lead-silver-zinc beneficiation process," Sci. Total Environ., vol. 659, p.41–52, 2019.

DOI: 10.1016/j.scitotenv.2018.12.318

[2] G. Calvo and A. Valero, "The influence of ore grade decline on energy consumption and GhG emissions : The case of gold," vol. 41, no. October 2021, p.1–11, 2022.

DOI: 10.1016/j.envdev.2021.100683

[3] C. Amaya, D. Bernal, S. Garnica, and M. Reslen, "Improved Roasting of Some Colombian Gold Ores," vol. 80, p.70–77, 2013.

[4] E. Yustanti, A. Guntara, and T. Wahyudi, "Ekstraksi Bijih Emas Sulfida Tatelu Minahasa Utara Menggunakan Reagen Ramah Lingkungan Tiosulfat," Tek. J. Sains dan Teknol., vol. 14, no. 2, p.97, 2018.

DOI: 10.36055/teknika.v14i2.5865

[5] Suratman, "Gold Recovery of Refractory Sulfide Concentrates Using Direct Cyanide Leaching with Nitrite as an Oxidant," 2016.

DOI: 10.30556/imj.vol19.no3.2016.541

[6] X. Wang, W. Qin, F. Jiao, C. Yang, Y. Cui, and W. Li, "Mineralogy and Pretreatment of a Refractory Gold," Minerals, vol. 9, p.406, 2019.

DOI: 10.3390/min9070406

[7] S. Handayani and Suratman, "Biooxidation: An Alternative Technology for Refractory Gold Ore Processing," 2017.

[8] G. Larrabure and J. C. F. Rodríguez-Reyes, "A review on the negative impact of different elements during cyanidation of gold and silver from refractory ores and strategies to optimize the leaching process," Minerals Engineering, vol. 173. 2021.

DOI: 10.1016/j.mineng.2021.107194

[9] P. Jose-Luis, A. Abadias, A. Valero, A. Valero, and M. Reuter, "The energy needed to concentrate minerals from common rocks: The case of copper ore," Energy, vol. 181, p.494–503, 2019.

DOI: 10.1016/j.energy.2019.05.145

[10] H. Qin, X. Guo, Q. Tian, D. Yu, and L. Zhang, "Recovery of gold from sulfide refractory gold ore: Oxidation roasting pretreatment and gold extraction," Miner. Eng., vol. 164, 2021.

DOI: 10.1016/j.mineng.2021.106822

[11] A. Sudarsono, Sudaryanto, and Pramusanto, "Perubahan struktur kristal dan indeks kerja bijih emas Cimanggu, Jawa Barat akibat pemanasan gelombang mikro," Proc. ITB, vol. 30, no. 3, p.25–32, 1998.

[12] T. Batar, "Theory and applications of microwave energy in communition," in Key Engineering Materials, 2004, vol. 264–268, no. II, p.1399–1402.

DOI: 10.4028/www.scientific.net/kem.264-268.1399

[13] M. Lovas, A. Zubrik, S. Dolinská, M. Lovás, I. Znamenáčková, and M. Kováčová, "The Application of Microwave Energy in Mineral Processing-a Review," Acta Montan. Slovaca Ročník, vol. 16, no. December, p.137–148, 2011, [Online]. Available: https://www.researchgate.net/publication/266873018.

[14] F. Lin, X. T. Feng, G. M. Lu, X. X. Su, S. P. Li, and J. yu Zhang, "Study on Microwave Heating Order and Electromagnetic Characteristics of Copper and Gold Ores," Rock Mech. Rock Eng., vol. 54, no. 5, p.2129–2143, 2021.

DOI: 10.1007/s00603-021-02376-4

[15] R. K. Amankwah and G. Ofori-Sarpong, "Microwave heating of gold ores for enhanced grindability and cyanide amenability," Miner. Eng., vol. 24, no. 6, p.541–544, May 2011.

DOI: 10.1016/j.mineng.2010.12.002

[16] K. Cho, H. Kim, E. Myung, O. Purev, N. Choi, and C. Park, "Recovery of gold from the refractory gold concentrate using microwave assisted leaching," Metals (Basel)., vol. 10, no. 5, May 2020.

DOI: 10.3390/met10050571

[17] N. C. Choi, B. J. Kim, K. Cho, S. Lee, and C. Y. Park, "Microwave pretreatment for thiourea leaching for gold concentrate," Metals (Basel)., vol. 7, no. 10, Oct. 2017.

DOI: 10.3390/met7100404

[18] X. Su, W. Mo, S. Ma, J. Yang, and M. Lin, "Experimental study on microwave pretreatment with some refractory flotation gold concentrate," in Advanced Materials Research, 2011, vol. 158, p.71–75.

DOI: 10.4028/www.scientific.net/AMR.158.71

[19] S. O. Adewuyi, H. A. M. Ahmed, and H. M. A. Ahmed, "Methods of ore pretreatment for comminution energy reduction," Minerals, vol. 10, no. 5, 2020.

DOI: 10.3390/min10050423

[20] B. Nanthakumar, C. A. Pickles, and S. Kelebek, "Microwave pretreatment of a double refractory gold ore," Miner. Eng., vol. 20, no. 11, p.1109–1119, Sep. 2007.

DOI: 10.1016/j.mineng.2007.04.003

[21] F. Zhu et al., "Gold extraction from cyanidation tailing using microwave chlorination roasting method," Metals (Basel)., vol. 8, no. 12, p.1–11, 2018.

DOI: 10.3390/met8121025

[22] R. K. Amankwah and C. A. Pickles, "Microwave roasting of a carbonaceous sulphidic gold concentrate," Miner. Eng., vol. 22, no. 13, p.1095–1101, 2009.

DOI: 10.1016/j.mineng.2009.02.012

[23] R. K. Amankwah and G. Ofori-Sarpong, "Microwave roasting of flash flotation concentrate containing pyrite, arsenopyrite and carbonaceous matter," Miner. Eng., vol. 151, 2020.

DOI: 10.1016/j.mineng.2020.106312

[24] R. Ahtiainen, J. Liipo, and M. Lundström, "Simultaneous sulfide oxidation and gold dissolution by cyanide-free leaching from refractory and double refractory gold concentrates," Miner. Eng., vol. 170, Aug. 2021.

DOI: 10.1016/j.mineng.2021.107042

[25] J. Kang, C. Yu, X. Wang, Z. Liu, and Y. Wang, "A novel non-cyanide extraction method of gold for high As-Sb-bearing refractory gold ore based on Mn-oxide ore acidic oxidation," Chem. Eng. Res. Des., vol. 189, p.347–357, 2023.

DOI: 10.1016/j.cherd.2022.11.035

[26] Arif, Syafrizal, and T. Indriati, "Karakteristik Mineralisasi Endapan Epitermal Pada Prospek Arinem," Geomine, vol. 8, no. 3, p.193–202, 2020.

DOI: 10.33536/jg.v8i3.614

[27] H. S. Purwanto, A. Harjanto, Y. Rizkianto, and D. Fatchurohman, "Gold mineralization and deposit type in Arinem Cisewu and its surrounding, Garut Regency, West Java, Indonesia," AIP Conf. Proc., vol. 2245, p.3–8, 2020.

DOI: 10.1063/5.0012447