硫酸锰室温固相球磨制备四氧化三锰

摘要

利用软锰矿吸收硫酸镁热解尾气二氧化硫制得硫酸锰,再与碳酸氢铵室温下固相球磨反应,制备出前躯体碳酸锰,经热分解获得四氧化三锰.分别考察了物料比、球磨时间、球料比等因素对硫酸锰转化率的影响,采用XRD对产物进行了分析.结果表明,在n(碳酸氢铵)∶n(硫酸锰)=3.5∶1、球磨时间为40 min、球料质量比为5∶1时,硫酸锰的转化率可达99.8％,将固相产物在1 000℃热解1h后所制备的四氧化三锰纯度为99.9％.该工艺操作简单,产品纯度高,成本低,为硫酸锰制备四氧化三锰提供了新的途径.%Manganese sulfate was prepared by reaction between pyrolusite and sulfur oxide from the pyrolysis of magnesium sulfate.Mn3O4 can be prepared by pyrolysing the precursor MnCO3.The precursor was synthesized by solid-state ball milling reaction between NH4HCO3 and MnSO4 · H2O at room temperature.Effects of materials mix ratio, milling time, and ball-feed mass ratio on the conversion of manganese sulfate were investigated respectively.The products were analyzed by XRD.Results showed that the conversion rate of MnSO4 · H2O could reach 99.8% under the conditions of mix ratio 3.5:1 (amount-of-substance ratio of NH4HCO3 to MnSO4 · H2O),milling time 40 min, and ball-feed mass ratio 5:1 .The Mn3O4, whose purity was 99.9%, can be prepared by pyrolysing manganese carbonate at 1 000℃ for 1 h.The process has the advantages of simple in operation, high product purity, and low cost, and it can provide a new route for the preparation Mn3O4 from MnSO4 · H2O.