摘要
采用长光路Fourier红外光谱 (LP FTIR)和高压液相色谱 (HPLC)技术研究了乙烷 /H2 O/O2 /N2 光化学体系中过氧化物的产生 .证实乙烷降解产物中有过氧化氢、乙基过氧化氢 (CH3 CH2 OOH ,EHP)和过氧乙酸 [CH3 C(O)OOH ,PAA],并首次发现了甲基过氧化氢 (CH3 OOH ,MHP)、羟甲基过氧化氢 (HOCH2 OOH ,HMHP)和过氧甲醚(CH3 OOCH3 ,DMP) .H2 O2 ,MHP和EHP的最大计算产率分别为 6 .8%,6 .4%和 6 .7%,是乙烷降解生成的主要过氧化产物 .MHP主要来自乙烷降解过程中的中间物乙醛的光解 .HMHP的检出表明乙烷降解过程中可能有Criegee中间体·CH2 OO·产生 .OH自由基引发的乙烷降解反应可能是对流层大气H2 O2 ,MHP及EHP的重要来源之一 .
Photochemical formation of peroxides in the ethane/H2O/O-2/N-2 system was studied with LP-FTIR and HPLC techniques. Hydrogen peroxide, ethyl hydroperoxide (CH3CH2OOH, EHP) and peroxyacetic acid [CH3(O)OOH, PAA] were proved to be the peroxide products in the degradation of ethane. Moreover, methyl hydroperoxide (CH3OOH, MBP), hydroxymethyl hydroperoxide (HOCH2OOH, HMHP) and dimethyl peroxide (CH3OOCH3, DMP) were identified for the first time in the system. The dominant peroxide products were H2O2, EHP and MHP with the maximum. calculated yields of 6.8%,6.4% and 6.7%, respectively. MHP was mainly generated from the photolysis of acet aldehyde formed in the degradation of ethane. The identification of HMHP provides an evidence for the formation of Criegee intermediate .CH2OO. in the degradation of ethane. The OH radical initiated degradation of ethane was possibly one of the main sources of H2O2, MHP and EHP in the troposphere.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2002年第2期251-255,共5页
Acta Chimica Sinica
基金
国家自然科学基金 (Nos.2 9837190
2 0 1770 0 2 )资助项目
