合成直链烷基苯环境友好固体酸催化剂的研究 Ⅲ .催化剂失活原因分析

采用固定床反应器,对催化剂的稳定性进行了初步评价。在120℃、空速相同、液固反应条件下,高苯烯比时催化剂的稳定性明显高于低苯烯比时;在苯烯比和空速相同、液固反应条件下,相对低温反应时,催化剂的稳定性明显高于高温反应。IR分析结果表明,同新鲜和反应后未失活的催化剂相比,失活后催化剂的活性组分特征衍射峰消失,出现的新的特征衍射峰可能同—CH基的振动有关。TG分析结果表明,失活后催化剂在空气流中焙烧,失重幅度比新鲜催化剂大。

Study of Environmental Friendly Solid Acid Catalysts for Synthesizing Linear Alkybenzene Ⅲ. Reason of Catalyst Deactivation

The catalyst stability had been primarily evaluated in a fixed bed reactor. At 120 ℃, and same space velocity and liquid-solid phase reaction conditions, the catalyst stability was higher at higher mole ratio of benzene to dodecene than at lower mole ratio. On the other hand, the stability obtained at a lower reaction temperature was higher than that at higher reaction temperature. Referring to IR curves and in comparison with fresh and used but not deactivated catalysts, the characteristic peaks of the catalytic component of the deactivated catalyst disappeared. The new peaks appeared instead were relevant to the vibration of -CH. TG results showed the weight lost extent of the deactivated catalyst was greater than that of fresh catalyst.