Studies of ozone initiated reactions of gaseous mercury: kinetics, product studies, and atmospheric implications
Studies of ozone initiated reactions of gaseous mercury: kinetics, product studies, and atmospheric implications
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DOI：
10.1039/b311150d
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发表时间：
2004-01
影响因子：
3.3
通讯作者：
B. Pal;P. Ariya
中科院分区：
文献类型：
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作者：
B. Pal;P. Ariya
在283-323 K、750 ± 1 Torr的温度范围内，研究了O3引发Hg 0氧化反应的动力学，以进一步了解汞的地球化学循环。动力学研究进行了使用相对和绝对技术，气相色谱质谱（GC-MS）。室温下的反应速率常数为（7.5 ± 0.9）× 10−19 cm 3 molecule−1 s−1。计算的活化能（EA）和指前因子（A）分别为11.7 ± 0.27 kJ mol−1和8.43 × 10−17 cm 3 molecule−1 s−1。第一次，O3引发的元素汞氧化的产品进行了研究，在气相中，从悬浮的气溶胶，并从反应器的壁，使用化学电离质谱（CI-MS），GC-MS和电感耦合等离子体质谱（ICP-MS）。在我们的实验条件下，主要鉴定产物是HgO，其主要吸附在反应壁上，并且有不到1%的反应产物从悬浮气溶胶收集在微米过滤器（0.5 μ）上。本文讨论了我们的动力学和产品研究的大气化学的影响。
Kinetics of O3 initiated oxidation reaction of Hg0 was performed in N2 and over the temperature range of 283–323 K at pressure of 750 ± 1 Torr, in order to provide further understanding of geochemical mercury cycling. Kinetic studies were carried out using relative and absolute techniques by gas chromatography with mass spectroscopy (GC-MS). The room temperature reaction rate constant was determined to be (7.5 ± 0.9) × 10−19 cm3 molecule−1 s−1. The calculated activation energy (EA) and pre-exponential factor (A) were 11.7 ± 0.27 kJ mol−1 and 8.43 × 10−17 cm3 molecule−1 s−1, respectively. For the first time, products of O3-initiated oxidation of elemental mercury have been studied in the gas-phase, from the suspended aerosols, and from the wall of the reactor, using chemical ionization mass spectrometry (CI-MS), GC-MS, and inductively coupled plasma mass spectrometry (ICP-MS). Under our experimental conditions, the dominant identified product was HgO, which was mainly adsorbed on the reaction walls, and there was less than 1% of the reaction product collected on the micron filters (0.5 μ) from the suspended aerosols. The implications of our kinetics and product studies to the chemistry of the atmosphere are herein discussed.