Effect of Stabilizer on Gold Leaching with Thiourea in Alkaline Solutions
The present work investigated the comparison of the effects of Na<sub>2</sub>SO<sub>3</sub> and Na<sub>2</sub>SiO<sub>3</sub> on thiourea stabilization, and a systematic study was undertaken to establish the effects of these stabilizers on the stabilit...
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MDPI AG
2022-01-01
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| Series: | Minerals |
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| Online Access: | https://www.mdpi.com/2075-163X/12/1/89 |
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| author | Wenjuan Li He Shang He Zhou Yongsheng Song Shuilin Zheng Xinlong Yang |
| author_facet | Wenjuan Li He Shang He Zhou Yongsheng Song Shuilin Zheng Xinlong Yang |
| author_sort | Wenjuan Li |
| collection | DOAJ |
| description | The present work investigated the comparison of the effects of Na<sub>2</sub>SO<sub>3</sub> and Na<sub>2</sub>SiO<sub>3</sub> on thiourea stabilization, and a systematic study was undertaken to establish the effects of these stabilizers on the stability of alkaline thiourea, both qualitatively and quantitatively. The effects of these stabilizers on the activation energy of alkaline thiourea gold leaching was also studied. The results showed that sodium silicate was more suitable as a stabilizer in this system than sodium sulfite because the peak current of gold dissolution with sodium sulfite was higher than that with sodium silicate, but the inhibition of thiourea decomposition by the former was less obvious than that of sodium silicate in the cyclic voltammetry curve. The quartz crystal microbalance results showed that the quality decreased to about 100 ng cm<sup>2</sup> in the presence of a stabilizer, while it increased to 300 ng cm<sup>2</sup> in the absence of the stabilizer. It is inferred that gold can be dissolved by alkaline thiourea in the presence of a stabilizer, while it cannot without a stabilizer because of the decomposition of thiourea. This assumption was confirmed by atomic force microscopy measurements. The surface activation energy of Au dissolution decreased from 183.76 to 98.07 kJ/moL with the addition of sodium silicate, indicating that Au dissolution was promoted with the chemical. |
| first_indexed | 2024-03-10T00:51:54Z |
| format | Article |
| id | doaj.art-76161cc417704c8e8dc89b5dbdf779a6 |
| institution | Directory Open Access Journal |
| issn | 2075-163X |
| language | English |
| last_indexed | 2024-03-10T00:51:54Z |
| publishDate | 2022-01-01 |
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| record_format | Article |
| series | Minerals |
| spelling | doaj.art-76161cc417704c8e8dc89b5dbdf779a62023-11-23T14:50:06ZengMDPI AGMinerals2075-163X2022-01-011218910.3390/min12010089Effect of Stabilizer on Gold Leaching with Thiourea in Alkaline SolutionsWenjuan Li0He Shang1He Zhou2Yongsheng Song3Shuilin Zheng4Xinlong Yang5School of Chemical & Environmental Engineering, China University of Mining & Technology, Beijing 100083, ChinaNational Engineering Research Center for Environment-Friendly Metallurgy in Producing Premium Non-Ferrous Metals, GRINM Resources and Environment Tech. Co., Ltd., Beijing 101407, ChinaNational Engineering Research Center for Environment-Friendly Metallurgy in Producing Premium Non-Ferrous Metals, GRINM Resources and Environment Tech. Co., Ltd., Beijing 101407, ChinaNational Engineering Research Center for Environment-Friendly Metallurgy in Producing Premium Non-Ferrous Metals, GRINM Resources and Environment Tech. Co., Ltd., Beijing 101407, ChinaSchool of Chemical & Environmental Engineering, China University of Mining & Technology, Beijing 100083, ChinaNational Engineering Research Center for Environment-Friendly Metallurgy in Producing Premium Non-Ferrous Metals, GRINM Resources and Environment Tech. Co., Ltd., Beijing 101407, ChinaThe present work investigated the comparison of the effects of Na<sub>2</sub>SO<sub>3</sub> and Na<sub>2</sub>SiO<sub>3</sub> on thiourea stabilization, and a systematic study was undertaken to establish the effects of these stabilizers on the stability of alkaline thiourea, both qualitatively and quantitatively. The effects of these stabilizers on the activation energy of alkaline thiourea gold leaching was also studied. The results showed that sodium silicate was more suitable as a stabilizer in this system than sodium sulfite because the peak current of gold dissolution with sodium sulfite was higher than that with sodium silicate, but the inhibition of thiourea decomposition by the former was less obvious than that of sodium silicate in the cyclic voltammetry curve. The quartz crystal microbalance results showed that the quality decreased to about 100 ng cm<sup>2</sup> in the presence of a stabilizer, while it increased to 300 ng cm<sup>2</sup> in the absence of the stabilizer. It is inferred that gold can be dissolved by alkaline thiourea in the presence of a stabilizer, while it cannot without a stabilizer because of the decomposition of thiourea. This assumption was confirmed by atomic force microscopy measurements. The surface activation energy of Au dissolution decreased from 183.76 to 98.07 kJ/moL with the addition of sodium silicate, indicating that Au dissolution was promoted with the chemical.https://www.mdpi.com/2075-163X/12/1/89alkaline thioureagoldstabilizerelectrochemical measurementquartz crystal microbalance |
| spellingShingle | Wenjuan Li He Shang He Zhou Yongsheng Song Shuilin Zheng Xinlong Yang Effect of Stabilizer on Gold Leaching with Thiourea in Alkaline Solutions Minerals alkaline thiourea gold stabilizer electrochemical measurement quartz crystal microbalance |
| title | Effect of Stabilizer on Gold Leaching with Thiourea in Alkaline Solutions |
| title_full | Effect of Stabilizer on Gold Leaching with Thiourea in Alkaline Solutions |
| title_fullStr | Effect of Stabilizer on Gold Leaching with Thiourea in Alkaline Solutions |
| title_full_unstemmed | Effect of Stabilizer on Gold Leaching with Thiourea in Alkaline Solutions |
| title_short | Effect of Stabilizer on Gold Leaching with Thiourea in Alkaline Solutions |
| title_sort | effect of stabilizer on gold leaching with thiourea in alkaline solutions |
| topic | alkaline thiourea gold stabilizer electrochemical measurement quartz crystal microbalance |
| url | https://www.mdpi.com/2075-163X/12/1/89 |
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