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891.
钼精矿焙烧烟道灰中铼的回收 总被引:2,自引:0,他引:2
含铼钼精矿经外加热式回转窑焙烧,伴生的稀贵金属铼进入烟尘,采用自激式高效收尘方式和装置进行回收,对焙烧烟尘中的主要成分进行分析,研究了浸出过程的主要影响因素:浸出剂、酸度、温度、时间、液固比等,把回收的含铼钼粉尘进行溶解,通过添加氧化剂,提高铼的浸出率,将含铼溶液,选择强碱性阴离子交换树脂201×7吸附,再用萃取剂萃取,用7N的氨水反萃,铼进入反萃液中,再用氨水解吸、蒸发、结晶得高铼酸铵。该工艺有效的回收了烟尘中的铼,粉尘回收率可达到98%以上,减少粉尘排放,降低环境污染;烟尘中的铼的浸出率在98%以上;溶液中铼的吸附率在99%以上,附铼树脂上铼的解析率在99%以上;铼酸铵纯度≥99.99%,总回收率≥98%;提高了矿产资源综合利用率及经济效益,为企业增加了新的经济增长点。 相似文献
892.
893.
钼酸铵是冶金化工生产的一种重要的深加工原料。以钼焙砂为原料生产钼酸铵的湿法冶炼工艺比较多,目前应用比较广泛的主要有2种,既经典氨浸法和离子交换法。本文对2种工艺作了利弊分析,研究认为离子交换法所排放的生产污水氨氮含量低,基于环境保护国策,我国今后钼酸铵生产项目的改扩建或新建工程宜采用离子交换工艺。 相似文献
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895.
C.A. Cerruto-Noya D.L. VanOverbeke C.A. Mireles DeWitt 《Journal of food science》2009,74(7):C519-C525
ABSTRACT: Paired USDA Select beef strip loins ( n = 10), aged 2 d, were injected with either an alkaline-based (3.6% sodium chloride, 1% Herbalox seasoning, adjusted to pH 10 with ammonium hydroxide [approximately 0.1%, FFC grade]) or a phosphate-based (3.6% sodium chloride, 1% Herbalox seasoning, 4.5% sodium tripolyphosphate) brine. Steaks were evaluated for 19 d. Overall, phosphate-injected steaks performed better than alkaline-injected steaks with respect to cook yield, water holding capacity, lipid oxidation, color stability, tenderness, and juiciness. Phosphate-injected steaks also had less purge than alkaline-injected steaks, as confirmed by composition analysis. Phosphate-injected steaks were higher in moisture and ash content, and were nearly 2% lower in protein content. Alkaline-injected steaks had significantly lower aerobic (approximately 1 log lower) and anaerobic (approximately 2 log lower) plate counts. Final meat pH probably contributed to the differences observed between treatments. The final pH of phosphate-injected steak was 5.99 while that of alkaline-injected steak was 5.73. Further research should be conducted to determine the concentration of ammonium hydroxide needed in the alkaline-based brine to increase the final meat pH to similar levels found in the phosphate-injected steaks. 相似文献
896.
A. Aracena Y. Vivar O. Jerez D. Vásquez 《Mineral Processing and Extractive Metallurgy Review》2013,34(5):317-323
In this work, the dissolution kinetics of tenorite (CuO) in a NH4OH-H2O system was studied. The studied temperature range was 5–55°C, ammonium hydroxide concentration between 0.1 and 0.75 M, and a particle size range of 5–24 µm. The stirring speed, pH of the ammonia solution, and various agents were also studied. The results indicated that the leaching of tenorite occurred quickly with a particle size of 5 µm in a 0.45 M solution of NH4OH for a pH value equal to 10.5. Dissolution of CuO also increases as temperature and the concentration of NH4OH increase. For concentrations less than 0.10 M, there is almost no leaching tenorite. By decreasing the particle size, the dissolution of CuO increase. Results show the stirring speed had no significant effect on the leaching rate of tenorite for values above 250 rpm. Leaching kinetics was analyzed using the model of the surface chemical reaction. The reaction rate was of the order of 2.2 with respect to the concentration of ammonium hydroxide and inversely proportional to the initial particle size. Activation energy of 59 kJ/mol was estimated for the temperature range of 5–55°C. 相似文献
897.
T. G. Harvey 《Mineral Processing and Extractive Metallurgy Review》2013,34(4):231-279
The use of ammonium carbonate for the extraction of metals such as copper and nickel is well known. Less well known is the fact that ammonium carbonate extraction was used for the commercial recovery of zinc decades before its application to either copper or nickel. This article reviews the published data on the Schnabel Process (the hydrometallurgical extraction of zinc by ammonium carbonate) covering the period of 1880–2005. 相似文献
898.
899.
900.
Pragnesh N. Dave Pravin N. Ram Shalini Chaturvedi 《Particulate Science and Technology》2013,31(6):677-681
Nanoferrite nanoparticles were synthesized by chemical coprecipitation method. The ferrite nanoparticles such as Zn, Mn, Ni, Co, and Cu were prepared. All nanoparticles were characterized by x-ray diffraction and scanning electron microscopy. The average particle of Zn, Mn, Co, Ni and Cu ferrite are 6.8, 2.7, 5.2, 1.1 and 3.9 nm respectively. The effect of ferrite nanoparticles on the thermal decomposition of ammonium per chlorate was studied using thermogravimetic analysis, differential scanning calorimetric (DSC) studies. Activation energy of high temperature decomposition of different alloy nanoparticles was calculated using DSC by Kissinger equation. The catalytic activity of nanoferrites is much sensitive to oxygen and may be effective to improve the thermal decomposition AP-based propellants. 相似文献