Uptake of methacrolein into aqueous solutions of sulfuric acid and hydrogen peroxide.
Uptake of methacrolein into aqueous solutions of sulfuric acid and hydrogen peroxide.
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DOI：
10.1021/jp2100649
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发表时间：
2012-01
期刊：
影响因子：
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通讯作者：
Ze Liu;Ling-Yan Wu;Tian-He Wang;M. Ge;Weigang Wang
中科院分区：
文献类型：
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作者：
Ze Liu;Ling-Yan Wu;Tian-He Wang;M. Ge;Weigang Wang
多相酸催化过氧化氢氧化被认为是异戊二烯及其气相氧化产物生成二次有机气溶胶（SOA）的潜在途径，但其动力学和化学机制仍不确定。在这里，我们报告了在253-293 K的温度范围内，甲基丙烯醛在硫酸和过氧化氢水溶液中的吸收的第一次测量。稳态吸收系数随硫酸浓度的增加和温度的降低而迅速增大。丙炔、丙酮和2,3-二羟基甲基丙烯酸被认为是合成产物。其化学机制可能是在酸性环境中过氧化氢氧化羰基和C = C双键，这可以解释大气细颗粒物中多羟基化合物含量高的原因。这些结果表明，过氧化氢在多相酸催化下氧化甲基丙烯醛会导致大气中特别是对流层上层的SOA质量增加。
Multiphase acid-catalyzed oxidation by hydrogen peroxide has been suggested to be a potential route to secondary organic aerosol (SOA) formation from isoprene and its gas-phase oxidation products, but the kinetics and chemical mechanism remain largely uncertain. Here we report the first measurement of uptake of methacrolein into aqueous solutions of sulfuric acid and hydrogen peroxide in the temperature range of 253-293 K. The steady-state uptake coefficients were acquired and increased quickly with increasing sulfuric acid concentration and decreasing temperature. Propyne, acetone, and 2,3-dihydroxymethacrylic acid were suggested as the products. The chemical mechanism is proposed to be the oxidation of carbonyl group and C═C double bonds by peroxide hydrogen in acidic environment, which could explain the large content of polyhydroxyl compounds in atmospheric fine particles. These results indicate that multiphase acid-catalyzed oxidation of methacrolein by hydrogen peroxide can contribute to SOA mass in the atmosphere, especially in the upper troposphere.