以自制酸改性膨润土负载ZnCl2为催化剂,采用傅里叶红外光谱( FT-IR) 和气相色谱-质谱联用(GC-MS)技术对松节油直接催化异构-歧化液相反应进行研究.FT-IR 分析表明,在反应产物谱图中蒎烯吸收峰3023 cm-1、1653 cm-1和3067 cm-1消失,苯环的骨架吸收峰1645 cm-1 和1456 cm-1、异丙基的特征峰1384 cm(1和1364 cm-1及对位双取代苯的吸收峰814 cm-1强度增大,说明松节油中蒎烯已完全反应,主要产物为对伞花烃;GC-MS 分析共分离出42个峰,鉴定出38个化合物,其中主要产物为对伞花烃、3-对孟烯和1-对孟烯,其质量分数分别为60.35%、10.28%和6.59%,蒎烯的转化率为100%,对伞花烃收率为68.10%;对酸改性膨润土负载ZnCl2催化松节油直接异构-歧化液相反应过程进行了探讨,结果表明原料中双环单萜烯发生了开环异构、重排和歧化主反应,同时倍半萜烯和双环单萜烯存在水合、脱氢、脱水和裂解等副反应,获得了酸改性膨润土负载ZnCl2催化松节油异构-歧化复杂反应网络图.%The isomerization-disproportionation of turpentine in liquid phase with acid-treated bentonite-supported ZnCl2 as catalyst is studied and characterized by Fourier infrared spectrophotometry (FI-IR) and gas chromatography-mass spectrometry (GC-MS). As a result of FI-IR, the absorbanc e peak of pinene at 3023 cm-1,1653 cm-1 and 3067 cm-1 almost disappeared, while the absorbance peak of benzene at 1645 cm-1 and 1456 cm-1,the characteristic peak of isopropyl at 1384 cm-1 and 1364 cm-1, and that at 814 cm-1 from p-substituent of benzene ring increased. It indicated that pinene was converted completely, mainly to p-cymene. 42 peaks were separated and 38 compounds were identified by GC-MS. The main products were p-cymene, 3-p-menthene and 1-p-menthene, with the mass fraction of 60.35 ％、 10.28 ％ and 6.59 ％, respectively. Complete conversion of pinene and 68.10％ yield of p-cymene was obtained. The reaction process was investigated. The results showed that the ring-opening isomerization, rearrangement and disproportionation of bicyclic monoterpenes were the main reactions. Simultaneously, some accompanying side reactions of sesquiterpene and bicyclic monoterpenes,such as hydration, dehydrogenation, dehydration and cracking occurred. The reaction networks of catalytic isomerization-disproportionation of turpentine on acid-treated bentonite-supported ZnCl2 was obtained.
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