I. Introduction At present, the selection of molybdenum ore is an important topic in the mineral processing process. In this study, refractory molybdenum ore beneficiation process carried out in a multi-metal system test. Molybdenum ore content of 0.18%, the gold content was 2.19g / t, silver content of 6.2g / t, metallic minerals are mainly molybdenite, galena, pyrite, sphalerite and brass ore; precious metal minerals There are natural gold and natural silver; gangue minerals are mainly quartz , calcite and barite . The oxidation rate of molybdenum in ore is as high as 60%. The results of multi-element analysis of ore minerals are shown in Table 1. The results of analysis of molybdenum phase of ore are shown in Table 2. The study first used mixed flotation to obtain a mixed concentrate with a molybdenum content of 4.21%, a gold content of 48.86 g/t, and a silver content of 84.80 g/t. The mixed concentrate was chemically treated to study the calcination temperature and calcination. The process parameters such as time, leaching agent concentration, liquid-solid ratio and leaching time were optimized. The final leaching rate of molybdenum was 86.6%, which effectively separated molybdenum from other valuable metals and realized the comprehensive recovery of minerals. Second, the mixed flotation test The mixed flotation test uses a mixed flotation process of coarse, triple and triple sweeps. In the grinding fineness of 70% -200 mesh conditions and using kerosene as the United butyl xanthate collector, sodium sulfide as the activator, sodium silicate gangue as inhibitors, # 2 oil as blowing The obtained mixed concentrate has a molybdenum content of 4.21%, a gold content of 48.86 g/t, and a silver content of 84.80 göt. The mixed concentrate has been selected several times, and the molybdenum grade is less than 10%. It is believed that this is due to the fact that most of the molybdenum in the flotation coarse concentrate exists in the form of oxides, and even some molybdenum in the form of sulfides is encapsulated in other minerals. Therefore, it is impossible to obtain effective enrichment of molybdenum by conventional physical beneficiation methods. Table 1 Results of multi-element analysis of ore chemistry (%) Table 2 % of ore molybdenum phase analysis results Third, molybdenum leaching test (1) Relationship between calcination temperature and molybdenum leaching rate When the calcination temperature is increased from 500 ° C to 800 ° C, the molybdenum leaching rate first increases and then decreases (see Figure 1). This is because molybdenum trioxide is easily sublimated at temperatures above 700 ° C to cause loss of molybdenum. Therefore, a suitable calcination temperature should be 650 °C. Figure 1 Relationship between calcination temperature and molybdenum leaching rate (2) Relationship between roasting time and molybdenum leaching rate When the calcination time was from 30 min to 120 min, the molybdenum leaching rate became better as the calcination time increased; after 120 min, there was no significant change (see Fig. 2). Therefore, the optimum baking time is 120 min. Figure 2 Relationship between calcination time and molybdenum leaching rate (3) Relationship between sodium carbonate concentration and molybdenum leaching rate The leaching agent is selected from sodium carbonate. The sodium carbonate leaching effect is stable, selective, non-decomposing, non-volatile, difficult to hydrolyze, and non-polluting. The sodium carbonate concentration was changed from 5% to 25%, and the test results are shown in Fig. 3. The results showed that with the increase of sodium carbonate concentration, the leaching rate of molybdenum increased first and then decreased. At 20% concentration, the leaching effect was the best. Figure 3 Relationship between sodium carbonate concentration and molybdenum leaching rate (IV) Relationship between liquid-solid ratio test and molybdenum leaching rate The liquid-solid ratio was changed from 3:1 to 8:1, and the test results are shown in Fig. 4. The results show that the molybdenum leaching rate increases with the increase of liquid-solid ratio. After the liquid-solid ratio is 5:1, the molybdenum leaching rate changes little. Figure 4 Relationship between liquid-solid ratio and molybdenum leaching rate (5) Relationship between leaching time and molybdenum leaching rate When the leaching time was from 60 min to 180 min, the molybdenum leaching rate did not change much (see Figure 5). Therefore, the leaching time has little effect on the molybdenum leaching rate. Figure 5 Relationship between leaching time and molybdenum leaching rate (6) Comprehensive condition test The molybdenum calcine was prepared under the conditions of a calcination temperature of 650 ° C and a calcination time of 2 h. For molybdenum calcination, a 20% sodium carbonate solution (liquid to solid ratio of 5:1) was stirred and leached for 1 h. The immersion liquid is purified by filtration and removal of impurities by sodium sulfide solution, and then dilute nitric acid is added dropwise to the filtrate to adjust the pH value (end point pH=8-9); the filtrate is heated and concentrated, and the heating is stopped at a density of 1.5 g/cm 3 and cooled to At about 30 ° C, sodium molybdate crystals were observed to precipitate. The test process is shown in Figure 6. The test results show that the molybdenum leaching rate is 86.6%, which realizes the effective separation of molybdenum from other valuable metals. Figure 6 Comprehensive condition test flow chart Fourth, the conclusion In view of the serious oxidation of the polymetallic molybdenum ore and the high mutual inclusion and close intercalation of the main minerals, the mixed concentrate obtained by mixed flotation has a molybdenum content of 4.21% and a gold content of 48.86 g/t. The content is 84.80g / t; the molybdenum recovery rate is 79.00%, the gold recovery rate is 85.58%, and the silver recovery rate is 47.21%, so that the main metal molybdenum, gold and silver in the ore are maximized. Considering that the molybdenum in the mixed concentrate cannot be enriched by conventional physical beneficiation methods, and the molybdenum cannot be separated from gold and silver, the chemical ore dressing method is used to treat the mixed concentrate, and the calcination temperature, roasting time, leaching agent concentration, liquid The process parameters such as solid ratio and leaching time were systematically studied, and the obtained molybdenum leaching rate was 86.6%, which effectively separated molybdenum from other valuable metals and made the mineral resources comprehensively utilized. Professional Dc Charging Station manufacturer is located in China, including DC Ev Charger,Dc Charging Pile,Dc Fast Charging, etc. Dc Ev Charger Dc Charging Station,Dc Ev Charger,Dc Charging Pile,Dc Fast Charging Shenzhen Hongjiali New Energy Co., Ltd. , https://www.hjlcharger.com