葡萄糖和葡萄糖酸钠对BrO3--SO32--Fe(CN)64-体系pH振荡的影响研究

摘要

The effects of glucose(Glu)and sodium gluconate(Glu-Na)on pH oscillation of the BrO3--SO32--Fe(CN)64-(BSF)system were investigated.The results indicated that,as the increase of Glu concentration,the pH amplitude of BSF system almost unchanged but the period increased in polynomial dependence.The results could be explained in terms of the propeties of Glu.Glu without acid-base characteristics can not interfer the pH of the system,however,Glu having reductive characteristics can participate in the oscillating reaction,and the coordination between the reductive product gluconic acid and Fe3+can decrease the reaction rate of BSF system.While,the increase of Glu-Na concentration results in decrease of the pH amplitude and the linear increase in period,which are attributed to the weak alkalinity of Glu-Na,its buffering effect and its coordination with Fe3+.%研究了葡萄糖(Glu)和葡萄糖酸钠(Glu-Na)对BrO3--SO32--Fe(CN)64-(BSF)体系pH振荡的影响.结果表明,随着Glu加入浓度的增加,体系的pH振幅基本不变,而振荡周期则按多项式关系增大,这是由于Glu不是酸碱化合物,因此不干扰体系pH变化,而Glu的还原反应及其还原产物葡萄糖酸与Fe3+的络合平衡则会减慢BSF体系反应速率;随着Glu-Na加入浓度的增加,体系的pH振幅则减小、周期线性增大,这是Glu-Na弱碱性、缓冲作用以及与Fe3+络合平衡的共同作用所致.