水中铁(Ⅲ)-草酸盐配合物光解产生羟基自由基的测定
DETERMINATION OF HYDROXYL RADICALS PRODUCED BY PHOTOLYSIS OF Fe(Ⅲ)-OXALATE COMPLEXES IN WATER
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摘要: 对铁(Ⅲ)草酸盐配合物光解过程中产生的·OH进行了气相色谱法间接测定在pH=3.5,异丙醇浓度为1mmol·l-1的条件下,经过125W高压汞灯(λ≥313nm)光照80min,Fe(Ⅲ)/草酸盐配比为93/120.7μmol·l-1的水溶液中,·OH的生成量为65.9μmol·l-1,·OH生成反应符合表观零级反应动力学模式,其生成速率为0.726μmol·l-1·min-1.同时蜒究了溶液pH值、Fe(Ⅲ)/草酸盐配比对·OH生成量的影响.
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关键词:
- 羟基自由基 /
- 铁(Ⅲ)-草酸盐配合物 /
- 光解 /
- 气相色谱
Abstract: By using 2-propanol as scavenger to produce acetone,the hydroxyl radical(·OH) produced by photolysis of Fe(Ⅲ)-oxalato complexes was determined with GC/FID.In the solution containing 9.3/120.7μmol·l-1 Fe(Ⅲ)/oxalate and 1mmol·l-1 2-propanol at pH 3.5,65.9μmol·l-1·OH produced after irradiation by 125W high pressure mercury lamp(λ≥313nm) for 80 minutes. Hydroxyl radical generation kinetics follows pseudo-zero-order reaction model with a rate of 0.726μmol·l-1·min-1.Effects of pH,and Fe(Ⅲ)/oxalate ratio on ·OH generation were exami-ned.-
Key words:
- hydroxyl radical /
- Fe(Ⅲ)-oxalate complexes /
- photolysis /
- GC
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