Waste electric and electronic equipment (WEEE) usually contains many recoverable and valuable elements, including gold and copper. Primitive technologies, such as aqua regia leaching and calcination, are still widely used in China, which has caused serious pollution in local environments. Chlorination is a feasible alternative for the …
A novel process based on chlorination roasting was proposed to simultaneously recover gold and zinc from refractory carbonaceous gold ore by using NaCl as chlorination agent. The …
A novel process based on chlorination roasting was proposed to simultaneously recover gold and zinc from refractory carbonaceous gold ore by using …
Trans. Nonferrous Met. Soc. China 30(2020) 1111âˆ'1123 Simultaneous extraction of gold and zinc from refractory carbonaceous gold ore by chlorination roasting process Hong-jun WANG1, Ya-li FENG1, Hao-ran LI2, Jin-xing KANG1 1.
Behavior of silver and lead in selective chlorination leaching process of gold-antimony alloy LIU Wei-feng( J ), YANG Tian-zu( < C ), XIA Xing( ) School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China Received 29 December 2008; accepted 23 March 2009 Abstract: The behavior of silver …
The study results showed that the technical indices of gold high-temperature chlorination rate of 85.19 % and iron recovery of 87.75 % were obtained from cyanide tailings (gold grade of 4.57 g·t −1, iron grade of 42.95 %) by chlorination–reduction one-step roasting . The new technology presents advantages of short process time, low …
This work was supported by the National Natural Science Foundation of China (U1702252) and (51604135). Recommended articles. References (33) ... the gold recovery and chlorine removal rates achieved 81.87 % and 94.85 %, respectively. The participation of CaCl 2 led to the generation of new components with a low melting point …
1. Introduction. Gold has been a symbol of wealth and remains an important part of the global currency reserves. Moreover, it is widely used in modern high-tech industries (Zhu et al., 2019) owing to its excellent physical and chemical properties.Gold not only has good thermal conductivity, electrical conductivity, and excellent ductility but also …
The direct chlorination of a pure gold was also studied up to a temperature of 1223 K.These experiments demonstrated that the precious metal is not attacked at that temperature, in agreement with the literature, which indicates that the reaction of direct chlorination of gold is produced at high temperatures (Panias and Neou-Syngouna, …
The main contributions are described as follows: (1) A complete process of gold recovery from sulfide refractory gold ore was proposed and the gold was effectively recovered; (2) Pyrite was first used to enhance the chlorination roasting; (3) Thermodynamic analysis and laboratory experiments verified the feasibility and reliability …
The efficiency of gold recovery reaches 99.8% when dibutyl carbitol is deployed as the additive. This cocrystallization is highly selective for square-planar …
A small amount of attention has been paid to the recovery of metals from gold tailing. Snyders et al. investigated several low temperatures pre-leaching process to enhance the gold recovery from a gold tailing and found that KOH and NaOH pre-leaching resulted in the highest gold recovery (63 and 62%) (Snyders et al., 2018).
Targeting resource recovery and up-to-standard discharge from electroplating wastewater treatment in this study, a hybrid process of stepwise alkalization, Fenton, and chlorination was proposed to treat real electroplating wastewater from Guangzhou, China, where pH was 1.1 and Ag, Fe, Ni, Cu, Zn, Cr, P, F, chemical oxygen demand (COD), …
In China alone, forward-looking data ... It is obvious that gold leaching process is the key step in hydrometallurgical gold recovery and different leaching systems have been reported, ... stage 1: electro-generated chlorine, pulp density 40 g/L, 2.0 mol/L HCl, temperature 25 °C, leaching time 165 min; stage 2: pulp density 160 g/L, 0.1 mol/L ...
The results show that gold chlorination reaction was controlled by the interfacial chemical reaction, and the apparent activation energy was 40.05 kJ/mol. …
The cyanide tailings used in this work were received from a Gold smeltery in Yan Tai of China. The major elements of the CT were determined with X-ray fluorescence (XRF), as shown in Table 1, are O, Fe, Si, Al, C and Ca.The contents of Au and Ag determined by fire assaying are 10.8 and 24.8 g/T (see Table 1), respectively.The X-ray …
equipment (WEEE) enter China, Africa and India for reproc-essing, much of it illegally, and o en using crude, hazardous and inefficient processes.5,6 Dumping and incinerating large ... In the hydrometallurgical recovery of gold from electronic waste (Fig. 2), the PCBs are leached by a suitable lixiviant, ...
Regarding waste printed circuit boards (WPCBs) as a secondary resource for recycling precious metals such as gold has become a worldwide consensus to conserve mineral resources, sustainably utilize resources, and prevent pollution. The dissolving of gold is the most important part for gold recycling because this process determines the …
Extraction of gold and silver in the selective chlorination roasting process of cyanidation tailing. ... Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming, Yunnan, P. R. China;Faculty of Metallurgical and Energy ... The best recovery values were 95.32% of Au and 85.32% …
Gold Leaching from a Refractory Gold Concentrate by the Method of Liquid Chlorination. Chao Li, Chao Li. ... 100083, China. Search for more papers by this author. Lifeng Zhang, Lifeng Zhang. School of Metallurgical and Ecological Engineering, University of Science and Technology Bejing, 30# Xueyuan Road, Beijing, 100083, China ...
Developing an eco-friendly, efficient, and highly selective gold-recovery technology is urgently needed in order to maintain sustainable environments and improve the utilization of resources. Here ...
To develop a cleaner production technology for the construction of secondary resources, this study researched the best chlorine source for the sustainable …
Metrics. Raising social awareness and environmental specifications on cyanide application force gold industry to search for alternative leaching reagents. …
Recycling gold has a significant impact on China's economy, technology, and traditional values and has become a research focal point in the gold sector [1,2]. ... The apparent activation energy of the high-temperature chlorination of gold and the acid leaching of vanadium from calcined slag is calculated to be E = 71.61kJ/mol and …
Thiosulfate is the most promising non-cyanide leaching reagent and the only reagent which found industrial application on gold recovery from a highly carbonaceous preg-robbing gold ore at Barrick ...
Addition of pyrite could promote the decomposition of CaCl 2.. FeS 2 and CaCl 2 were converted to Cl 2, CaSO 4 and Fe 2 O 3.. Addition of pyrite, the recovery efficiency of Au was increased by 42.66%. • Compared to other additives, this process reduced the emission of harmful gases.
A practical way to express the results obtained in all the assays is as a function of the percentual extraction, X, which was defined as: X (%) = 100 (M 0 C 0-M f C f) / (M 0 C 0) being C 0 the initial gold concentration in the sample (m 2), C f final gold concentration in chlorination residue (m 3), both concentrations expressed in ppm, M 0 ...
Pyrite cinder is the by-product during the production of sulfuric acid from pyrites. The output of China's sulfuric acid from pyrites was about 16.52 million tons in 2018 [].As a result, more than 10 million tons of pyrite cinders were produced [].Difficulties are met during the utilization of pyrite cinders due to the non-ferrous metal contents, the …
Chlorination was extensively used in gold extraction in the late 19th century until the development of cyanidation, a more economical process with a higher stability complex, rapidly replacing chlorination. ... The released dicyanamide groups are much less toxic than cyanide. The gold recovery was 34.8 % under a pH value of 12 and a …
