Rate constants for the gas-phase reactions of a series of alkylnaphthalenes with the nitrate radical.
Rate constants for the gas-phase reactions of a series of alkylnaphthalenes with the nitrate radical.
复制标题
一系列烷基萘与硝酸根的气相反应的速率常数。
DOI：
10.1021/es026015
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发表时间：
2002
影响因子：
11.4
通讯作者：
J. Arey
中科院分区：
文献类型：
--
作者：
P. T. Phousongphouang;J. Arey
萘及其甲基、乙基和二甲基衍生物是半挥发性多环芳烃，预计存在于周围大气的气相中，并在夜间与硝酸根(NO3)发生气相反应而降解。用相对速率法测定了298+/-2K和大气压下NO3自由基与一系列烷基萘的气相反应速率常数。所研究的化合物是1-和2-甲基萘(1-和2-MN)，1-和2-乙基萘(1-和2-烯)，以及10个二甲基萘异构体(1，2-，1，3-，1，4-，1，5-，1，6-，1，7-，1，8-，2，3-，2，6-和2，7-DMN)。在加利福尼亚州河滨的采样表明，除了1，8-DMN外，环境空气中很容易检测到这些烷基萘。萘和烷基萘与硝酸根的反应通过自由基的初始加成而进行，生成芳香族-硝酸根加合物(速率常数k(A))，它要么分解成反应物(速率常数kb)，要么与NO2反应生成产物(速率常数k(C))。以萘为参比化合物，得到硝酸根反应的(k(A)k(C)/k(B))值(单位为10(-28)cm(6)分子(-2)S(-1)，误差为两个最小二乘标准差)：1-MN，7.15+/-0.37；2-MN，10.2+/-1.0；1-烯，9.82+/-0.69；2-烯，7.99+/-0.99；1，2-DMN，64.0+/-2.3；1，3-DMN，21.3+/-1.2；1，4-DMN，13.0+/-0.5；1，5-DMN，14.1+/-1.3；1，6-DMN，16.5+/-1.8；1，7-DMN，13.5+/-0.7；1，8-DMN，212+/-59；2，3-DMN，15.2+/-0.5；2，6-DMN，21.2+/-1.6；2，7-DMN，21.0+/-1.5。
Naphthalene and its methyl-, ethyl-, and dimethyl-derivatives are semivolatile polycyclic aromatic hydrocarbons expected to be in the gas phase in ambient atmospheres and are subject to nighttime degradation by gas-phase reactions with the nitrate (NO3) radical. Using a relative rate method, rate constants for the gas-phase reactions of NO3 radicals with a series of alkylnaphthalenes have been measured at 298 +/- 2 K and atmospheric pressure of air. The compounds studied were 1- and 2-methylnaphthalene (1- and 2-MN), 1- and 2-ethylnaphthalene (1- and 2-EN), and the 10 dimethylnaphthalene isomers (1,2-, 1,3-, 1,4-,1,5-, 1,6-, 1,7-, 1,8-, 2,3-, 2,6-, and 2,7-DMN). Sampling in Riverside, CA showed that these alkylnaphthalenes were readily detected in ambient air, with the exception of 1,8-DMN. The reactions of naphthalene and the alkylnaphthalenes with NO3 radicals proceed by initial addition of the radical to form an aromatic-NO3 adduct (with rate constant k(a)) which either decomposes back to reactants (with rate constant kb) or reacts with NO2 to form products (with rate constant k(c). Using naphthalene as the reference compound, the values of (k(a)k(c)/k(b)) obtained for the NO3 radical reactions (in units of 10(-28) cm(6) molecule(-2) S(-1), indicated errors are two least-squares standard deviations) were as follows: 1-MN, 7.15 +/- 0.37; 2-MN, 10.2 +/- 1.0; 1-EN, 9.82 +/- 0.69; 2-EN, 7.99 +/- 0.99; 1,2-DMN, 64.0 +/- 2.3; 1,3-DMN, 21.3 +/- 1.2; 1,4-DMN, 13.0 +/- 0.5; 1,5-DMN, 14.1 +/- 1.3; 1,6-DMN, 16.5 +/- 1.8; 1,7-DMN, 13.5 +/- 0.7; 1,8-DMN, 212 +/- 59; 2,3-DMN, 15.2 +/- 0.5; 2,6-DMN, 21.2 +/- 1.6; 2,7-DMN, 21.0 +/- 1.5.