固体强酸催化剂S_2O_8~(2-)/ZrO_2-Al_2O_3-M_2O_3(M=Cr,Ce,La)的制备

固体强酸具有酸强度高 ,不腐蚀设备 ,不污染环境 ,与产物分离方便等特点 ,是一种对环境友好的催化剂。业已发现固体强酸对许多重要的有机反应如烃类异构化、傅克酰基化、傅克烷基化、酯化、缩合、聚合、氧化等具有良好的催化活性 ,可替代传统的浓 H2 SO4 及 Al Cl3、HF等高污染催化剂。在前文 [1]基础上 ,本文通过添加 Cr2 O3、Ce2 O3和 La2 O3对催化剂 S2 O2 - 8/Zr O2 - Al2 O3改进后制备出 S2 O2 - 8/Zr O2 -Al2 O3- M2 O3( M=Cr,Ce,La)系列固体强酸催化剂 ,用对乙酸和正丁醇的酯化转化率评价了催化活性 ,用 XRD、BET、流…

Preparation of Solid Strong Acid Catalysts S_2O _8~(2-)/ZrO_2-Al_2O_3-M_2O_3(M=Cr,Ce,La)

Three kinds of new type solid strong acid catalysts S_2O 2-_8/ZrO_2-Al_2O_3-M_2O_3(M=Cr,Ce,La) were prepared. Their crystal structure, surface area, acid strength and sulfur content were determined by means of XRD, BET, flow Hammett indicator method and chemical analysis. Their catalytic activities in esterification reaction of acetic acid with n-butanol were studied. The results showed that ZrO_2 in the catalysts mainly in tetragonal phase and few in monoclinic phase. The tetragonal phase of ZrO_2 and S_2O 2-_8 are the key factors that guarantee the catalytic activity. Incorporation of appropriate amounts of metallic oxides(Cr_2O_3,Ce_2O_3,La_2O_3) into the catalyst favors the stabilization of sulfur species and surface area, which increase the activity sites on the catalyst. The experimental results showed that three catalysts S_2O 2-_8/ZrO_2-Al_2O_3(2%)-M_2O_3(1%)(M=Cr,Ce,La) had higher catalytic activity in mentioned esterification, with the conversion of acetic acid reached 96.8%, 95.7% and 96.1%, respectively. The preparation condition of the catalysts showed great influence on the catalytic activity.