钨渣回收制备四氧化三锰新工艺

Novel process for preparation of mangano-manganic oxide from tungsten residue

研究从钨渣中回收锰的新工艺,通过钨渣的低温硫酸化焙烧、烧结块浸出、浸出液除杂、溶液中水解沉锰及氢氧化锰氧化获得Mn3O4粉末,采用SEM和XRD对产品粉末进行分析。结果表明:在浓硫酸过量150%、焙烧时间90 min、浸出温度98℃、浸出时间120 min的条件下,Mn浸出率达到88.9%。浸出液可以通过硫化物沉淀除重金属、硫酸复盐沉淀法深度净化除杂、中和水解除Fe,水解沉锰也有一定的净化作用,溶液pH值为6.56时,除铁率达到99.91%。净化液经水解沉锰后采用10%H2O2氧化,在氢氧化锰氧化过程中,溶液pH值对产物物相的影响较大;溶液pH值为8时在50℃沉锰,并以过量150%的H2O2氧化反应20min,获得粒度小于0.1μm的Mn3O4粉末。

In order to recover manganese from tungsten residue,a corresponding technology to prepare mangano-manganic oxide was adopted as follows： low temperature sulfating roasting tungsten residue,leaching,removal of impurities in leachate,precipitation of manganese and oxidation of manganese hydroxide.The product was analyzed by SEM and XRD.The results of roasting and leaching show that the recovery of Mn is 88.9% after roasting with 150% excess of concentrated H2SO4 for 90 min and leaching at 98 ℃ for 120 min.The purification of leaching liquor can be carried out through sulfide precipitation and complex sulfate precipitation and neutralizing hydrolysis.In addition precipitation in Mn by hydrolysis favors the purification of the leach liquor.The removal of iron reaches 99.91% when the pH value of solution is 6.56.The precipitate bearing Mn from the leach liquor was oxidized with 10% H2O2（mass fraction）.The results show that the pH value of solution in the oxidation process has significant effect on the products.The mangano-manganic oxide with diameter of less than 0.1 μm is prepared as oxidizing with 150% excess of H2O2 for 20 min after precipitating at 50 ℃ from the liquor with pH value of 8.