苯甲醚和苯乙醚氧化特性及其产物

Oxidation characteristics and products of anisole and phenetole

设计了跟踪测定苯甲醚、苯乙醚与氧气加热氧化反应过程的小型压力容器试验装置(MCPVT),得到了它们的压力-时间、温度-时间的变化规律。用碘量法测定了两种醚氧化过程中过氧化物的生成,采用气相色谱-质谱联用仪(GC-MS)分析了氧化产物。结果表明,苯甲醚、苯乙醚在195℃时会发生明显的放热氧化反应。两种醚生成过氧化物最高浓度时的温度均为160℃。苯甲醚在反应温度≤200℃时,氧化产物为甲酸苯酯、邻甲氧基苯酚;反应温度≥210℃时,氧化产物变得复杂,主要有酚、醇、醛、酸和酯等。苯乙醚在反应温度≤150℃,氧化产物为乙醛、苯酚、乙酸苯酯、邻乙氧基苯酚;反应温度≥160℃时,氧化产物有二十多种,主要有乙醛、乙酸、苯酚、乙酸苯酯、邻乙氧基苯酚等。

A mini closed pressure vessel test（MCPVT） was designed,it can track and determine the heated oxidation reaction process of anisole and phenetole with oxygen,and the change rules of pressuretime,temperature-time were obtained.Peroxide from the heated oxidation reaction of anisole and phenetole were titrated by the iodine volume method and the products were analysed by GC-MS.The results showed that exothermic oxidation reaction of anisole and phenetole occurred at 195 ℃.The peroxide concentration of both ethers reached the maximun at 160 ℃.The oxidation products of anisole were formic acid phenyl ester and o-methoxy phenol when the reaction temperature was lower than 200 ℃.However,the oxidation products were complex,including phenols,alcohols,aldehydes,acids,esters when the reaction temperature was higher than 210 ℃.The oxidation products of phenetole were acetaldehyde,phenol,acetic acid phenyl ester and o-ethoxy phenol when the reaction temperature was lower than 150 ℃.There were 20 kinds of oxidation products,when the reaction temperature was higher than 160 ℃.Main of them were acetaldehyde,acetic acid,phenol,acetic acid phenyl ester,o-ethoxy phenol.