Zeta Potential of Beta Zeolites: Influence of Structure, Acidity, pH, Temperature and Concentration
Xuan Liu1, Päivi Mäki-Arvela2, Atte Aho3
1Laboratory of Industrial Chemistry and Reaction Engineering, Faculty of Science and Engineering, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, FI-20500 Turku/Åbo, Finland. xuan.liu@abo.fi.
Abstract:
Measurements of the zeta potential of solid heterogeneous supports are important for preparation of metal supported catalysts and for shaping zeolites into extrudates. In the current work, different types of heterogeneous support materials such as SiO₂, Al₂O₃, and a range of beta zeolites of different silica- to-alumina ratio were analysed. It was observed that parameters such as temperature, pH and acidity significantly affect the zeta potential. In several instances, depending on the materials’ acidity and microstructure, maxima in zeta potential were observed. The solid materials were thoroughly characterized using XRD, SEM, EDX, TEM, nitrogen physisorption, Al-NMR and FTIR with pyridine before zeta potential measurements.
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