论文部分内容阅读
用高温水蒸汽处理及酸洗的两步法,制备了硅铝比为15.8—186的脱铝丝光沸石(DHM)由NH_3的TPD和吸附吡啶红外光谱研究了各种DHM的酸中心数、酸强度以及B和L酸中心随丝光沸石脱铝的变化规律。用脉冲微反技术研究了芳烃在DHM上的反应活性和选择性,并将酸性与催化性能同沸石的微观结构进行了关联,发现随着脱铝,酸性逐渐变弱,与骨架铝T(1)关联的酸中心强度最强,与T(2)关联的其次,与T(4)关联的较弱,与T(2)和T(4)相关的酸中心分别是甲苯歧化和二甲苯异构化的活性中心,某些芳烃反应所需的酸强度顺序为甲苯脱烷基>甲苯歧化>二甲苯歧化>二甲苯异构化。
High temperature steam treatment and acid pickling two-step method, the preparation of the aluminosilicate ratio of 15.8-186 dealuminated mordenite (DHM) by NH_3 TPD and pyridine adsorption infrared spectroscopy of various DHM acid center number, acid Strength and B and L acid center with the mordenite dealuminated changes. The reactivity and selectivity of aromatics on DHM were studied by pulsed micro-inversion technique. The relationship between acidity and catalytic activity was also studied. The results showed that with the dealumination, the acidity gradually weakened, The associated acid centers were the strongest, followed by T (2), followed by the weaker T (4) -associated acid centers associated with T (2) and T (4) were toluene disproportionation and xylene isomerization In the active center, the order of acidity required for some aromatics is toluene dealkylation> toluene disproportionation> xylene disproportionation> xylene isomerization.