气相色谱-质谱法分析环己酮氨肟化体系中失活催化剂上可溶性沉积物的组成

Determination of soluble deposits on deactived catalyst of cyclohexanone ammoximation system by gas chromatographymass spectrometry

利用气相色谱-质谱(GC-MS)联用技术,对环己酮氨肟化体系中失活催化剂上的可溶性沉积物进行了分析。分析液样品的制备采用了HF溶解-乙醚萃取法。GC条件:HP-5型石英毛细管色谱柱(30m×0.25mm×0.25μm),载气为He,流速为0.8mL/min;柱箱程序升温,初始温度为40℃,以20℃/min升至240℃,恒温5min;进样室温度为250℃,进样量为0.2μL。MS条件:电子轰击离子源,轰击能量为70eV,质量扫描范围为10～450m/z,检测器温度为280℃。检测结果表明,失活TS-1催化剂的可溶性沉积物为环己酮的氧化或还原产物、环己酮的二聚物、环己酮肟深度反应产物、叔丁基环己酮及少量其他有机杂质,此结果为分析催化剂上沉积物的形成机理及反应溶剂的选择提供了实验基础。

The soluble deposits on deactived catalyst of cyclohexanone ammoximation system were analyzed by gas chromatography-mass spectrometry（GC-MS）.Sample for analyzing was prepared by HF dissolution and ether extraction method.The GC conditions were as follows： an HP-5 quartz capillary column（30 m× 0.25 mm×0.25 μm）,flowrate of carrier gas helium 0.8 mL/min;oven temperature program started at 40 ℃,then increased to 240 ℃ at a rate of 20 ℃/min,finally held at this temperature for 5 min;inlet temperature 250 ℃,sample volume 0.2 μL.The MS conditions were that electron impact energy of mass spectrometer 70 eV,mass range 10~450 m/z,detector temperature 280 ℃.The result shows that the main soluble deposits on deactived TS-1 are products of cyclohexanone oxidation/ reduction,dimers of cyclohexanone,continuous reaction products of cyclohexanone oxime,tert-butylcyclohexanone and a small quantity of other organic compounds.The testing conclusion might be useful in solvent selection and mechanism investigation of deposits formation on TS-1.