The deactivation mechanism of TS-1 used in the organic solvent-free cyclohexanone ammoximation based on ceramic membrane reactor was investigated. The framework structure, crystal parameters, specific surface area and pore volume and the major composition of organic, of fresh and deactivated TS-1 zeolites were examined by XRD, FT-IR, N2 adsorption, TGA/DSC and GC-MS techniques. The results have shown that the dissolution of silicon has taken place in the reaction system, but the topological structure and crystal volume of deactivated TS-1 zeolite remained almost the same to the fresh one. The catalyst deactivation was mainly due to the adsorption of cyclohexanone, cyclohexanone oxime and by-product on the surface and channel of TS-1 zeolite, and because of this, the specific surface area of TS-1 catalysts decreased by 52.6% and the pore volume decreased by 41.6%. The catalyst activity can be recovered by air calcination at 600℃for 3 h.%基于陶瓷膜反应器开发出无有机溶剂的环己酮氨肟化新工艺,探讨TS-1催化剂失活机制.采用XRD及Rietveld全谱拟合、FT-IR、N2吸附-脱附、TGA/DSC、GC-MS等手段对TS-1分子筛的骨架结构、晶胞参数、比表面积和有机物种类进行了表征分析.结果表明,无有机溶剂的环己酮氨肟化反应过程中,存在硅流失的现象,但TS-1骨架完整,晶胞参数未明显变化;环己酮、环己酮肟及反应副产物等吸附在TS-1催化剂的表面及孔道内,使比表面积下降52.6%、孔体积减少了41.6%,是造成TS-1失活的主要原因,空气氛围中于600℃煅烧3 h,可以恢复催化剂的活性.
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