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研究了(NH_4)_2SO_3对MnO_2的还原过程。通过1-(1-α)~(1/3)=kt模型描述了反应的状态。在研究中发现氨和硫酸铵浓度对MnO_2的还原动态特性无影响。估计的活化能为62kJ/mol。还原的产物是Mn~(2+)、Mn~(3+)和Mn~(4+)的混合物,当反应温度从353K上升到383K时,Mn~(2+)/Mn~(3+)比从1.10增加到5.12,这表明在高温时易形成低价的锰。尽管能形成各种产物,但收缩模型的研究表明,没有一种产品能在二氧化锰颗粒上形成一个保护层,由于整个还原动态过程是由该模型支配的,故在反应中任何中间过程的Mn~(3+)还原成Mn~(2+)时均按同样的过程进行。根据试验条件,连二亚硫酸盐的含量变化范围为1.0～2.33g/L,这表明主要形成了硫酸盐,而不是连二亚硫酸盐。
The reduction of MnO_2 by (NH_4) _2SO_3 was studied. The state of the reaction is described by the 1- (1-α) ~ (1/3) = kt model. In the study, ammonia and ammonium sulfate concentrations were found to have no effect on the reduction kinetics of MnO 2. The estimated activation energy is 62 kJ / mol. The product of reduction is a mixture of Mn ~ (2 +), Mn ~ (3+) and Mn ~ (4 +). When the reaction temperature rises from 353K to 383K, Increased from 1.10 to 5.12, indicating the formation of cheap manganese at high temperatures. Although various products can be formed, the study of shrinkage models shows that none of the products form a protective layer on the particles of manganese dioxide. Since the overall reduction kinetics is dominated by the model, any intermediate process in the reaction The same procedure was followed when Mn ~ (3 +) was reduced to Mn ~ (2+). Depending on the test conditions, the content of dithionite varies from 1.0 to 2.33 g / L, indicating that predominantly sulphate is formed rather than dithionite.