碱性条件下Sn(Ⅱ)还原TcO_4~-的动力学研究

详细信息

Reduction Kinetics of TcO_4~- by Sn(Ⅱ) in Basic Medium

摘要: 为了解在碱性介质中Sn(Ⅱ)还原TcO-4的动力学性质,用萃取法和液闪计数法研究了TcO-4,Sn(Ⅱ),OH-浓度和温度对Sn(Ⅱ)还原TcO-4反应速率的影响。结果表明,TcO-4被Sn(Ⅱ)还原为Tc(Ⅳ),Sn(Ⅱ)与TcO-4发生氧化还原反应的计量式可表示为:3Sn(Ⅱ)+2Tc(Ⅶ)3Sn(Ⅳ)+2Tc(Ⅳ)。在碱性介质中,Sn(Ⅱ)还原TcO-4的化学反应速率方程为:-dc(TcO-4)/dt=kc(TcO-4)c-0.478(OH-)c0.629(Sn(Ⅱ)),反应的活化能Ea=29.08kJ/mol。
- TcO-4 /
- Sn(Ⅱ) /
- 萃取 /
- 化学动力学
Abstract: The reduction kinetics of TcO_4~-by Sn(Ⅱ) in basic medium is studied. The influence of the concentrations of TcO_4, Sn(Ⅱ), OH- and temperature on the reaction rate is investigated by extraction separation and liquid scintillation measurement for TcO_4 concentration. Experimental results show that TcO_4 is reduced to Tc(Ⅳ) by Sn(Ⅱ) and the stoichiometry of the reduction can be expressed as: 3Sn(Ⅱ)+2Tc(Ⅶ)3Sn(Ⅳ)+2Tc(Ⅳ). The reaction rate expression is obtained as: -dc(TcO_4)/dt=kc(TcO_4)c -0.478 (OH-)c 0.629 (Sn(Ⅱ)). The activation energy of the reaction is about 29.08 kJ/mol.
- TcO_4~- /
- Sn(Ⅱ) /
- extraction /
- chemical kinetics

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