Method for associated producing ammonium molybdate and manganese sulfate by roasting molybdenite and pyrolusite

Abstract

This invention discloses a method for combined production of ammonium molybdate and manganese sulfate by co-torrefication of molybdenite and pyrolusite. The method comprises: (1) mixing molybdenite and pyrolusite at a ratio of nMnO2:nMoS2 = 1.0-10.0; (2) co-torrefying the mixture at 350-950 deg.C for 60-360 min; (3) acidolyzing with an inorganic acid at 5-95 deg.C and a liquid / solid ratio of 1.0-50.0 for 5-300 min until the pH value is below 5.5; (4) extracting the leaching solution with solvent, separating to obtain an organic phase containing Mo and an aqueous phase containing Mn, and back-extracting the organic phase with ammonia to obtain ammonium molybdate; (5) processing into ammonium molybdate and manganese sulfate products by using the present metallurgical technique. The method has such advantages as short process, simple apparatus, low energy consumption, little pollution, high metal recovery rate, and high product quality.

Description

technical field [0001] The invention relates to a method for directly producing ammonium molybdate and manganese sulfate by using molybdenite and pyrolusite. Background technique [0002] Molybdenum is a very important rare metal element, widely used in metallurgy, chemical industry, machinery, aerospace and biology and other fields, and has become an increasingly important metal material. my country has large reserves of molybdenum resources, wide distribution, many types, and many compound ores. The proven reserves are 4.15Mt, ranking second in the world. It is one of the countries with the largest export volume of molybdenum products in the world. The production capacity of molybdenum concentrate is rapid. increase, and has reached 70kt / a at present. [0003] During the 1960s and 1970s, almost 90% of the production of pure molybdenum compounds in the world used the roasting-ammonia leaching process. The traditional roasting-ammonia leaching process is to oxidize and roas...

AI Technical Summary

Problems solved by technology

The lime-molybdenum concentrate co-roasting process developed in the late 1980s is aimed at the SO2 of molybdenite during the roasting process. 2 Pollution and recovery of associated rhenium elements, the main role of lime is to fix sulfur (CaSO 4 ) and solid rhenium (Ca(ReO 4 ) 2 ), although the recoveries of molybdenum and rhenium can be increased to 95% and 74%, respectively, SO 2 The pollution problem has not been well resolved, and the consumption of raw materials, waste residue and waste liquid in the production process has increased significantly, so it is difficult to popularize and apply (Liu Yinghan. Research on the extraction of molybdenum and rhenium from rhenium-containing molybdenum concentrates[J]. Journal of Jiangxi University (Natural Science Edition), 1989, 13(1): 88~95.)

At present, more than 30 domestic manufacturers adopt the reduction roasting-sulfuric acid leaching process to produce manganese sulfate, with a production capacity of 30,000 t / a, and the reduction roasting temperature requirement is as high as 700-1000°C. At the same time, a large amount of pulverized coal is consumed as a reducing agent. The process consumes a lot of energy, takes a long time, and produces a lot of CO 2 and CO exhaust