The kinetics of complex formation between Ti(IV) and hydrogen peroxide
The kinetics of complex formation between Ti(IV) and hydrogen peroxide
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DOI：
10.1002/kin.20259
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发表时间：
2007-08-01
影响因子：
1.5
通讯作者：
Tyree, Michael
中科院分区：
文献类型：
--
作者：
O'Sullivan, Daniel W.;Tyree, Michael
研究了Ti（IV）OSO 4与过氧化氢反应和羟甲基过氧化氢（HMHP）水解形成钛-过氧化物[TiO 22 +]络合物的动力学，以确定Ti（IV）OSO 4是否可用于区分混合溶液中的过氧化氢和HMHP。停流分析耦合到紫外可见光谱被用来检查在不同温度下的反应动力学。在405 nm处，[TiO_（22+）]络合物的摩尔吸光系数为679.5 +/- 20.8 L mol（-1）cm（-1）。过氧化氢和Ti（IV）OSO 4之间的反应相对于Ti（IV）OSO 4和H2 O2均为一级反应，在25 ℃下的速率常数为5.70 +/- 0.18 x 10（4）M-1 s（-1），活化能E-a = 40.5 +/- 1.9 kJ mol（-1）。HMHP水解的速率常数在pH 8.5时为4.3 x 10（-3）s（-1）。由于Ti（IV）OSO 4和过氧化氢之间的络合物形成速率比HMHP的水解速率快得多，因此Ti（IV）OSO 4反应与时间依赖性紫外-可见光谱测量耦合可用于区分溶液中的过氧化氢和HMHP。(c)2007 Wiley Periodicals，Inc.
The kinetics of the formation of the titanium-peroxide [TiO22+] complex from the reaction of Ti(IV)OSO4 with hydrogen peroxide and the hydrolysis of hydroxymethyl hydroperoxide (HMHP) were examined to determine whether Ti(IV)OSO4 could be used to distinguish between hydrogen peroxide and HMHP in mixed solutions. Stopped-flow analysis coupled to UV-vis spectroscopy was used to examine the reaction kinetics at various temperatures. The molar absorptivity (epsilon) of the [TiO22+] complex was found to be 679.5 +/- 20.8 L mol(-1) cm(-1) at 405 nm. The reaction between hydrogen peroxide and Ti(IV)OSO4 was first order with respect to both Ti(IV)OSO4 and H2O2 with a rate constant of 5.70 +/- 0.18 x 10(4) M-1 s(-1) at 25 degrees C, and an activation energy, E-a = 40.5 +/- 1.9 kJ mol(-1). The rate constant for the hydrolysis of HMHP was 4.3 x 10(-3) s(-1) at pH 8.5. Since the rate of complex formation between Ti(IV)OSO4 and hydrogen peroxide is much faster than the rate of hydrolysis of HMHP, the Ti(IV)OSO4 reaction coupled to time-dependent UV-vis spectroscopic measurements can be used to distinguish between hydrogen peroxide and HMHP in solution. (c) 2007 Wiley Periodicals, Inc.