Basicity and Crystal Phase of Mesoporous K₂O-MgO/ZrO₂-La₂O₃ Catalyst

Abstract:

A new solid base, mesoporous K₂O-MgO/ZrO₂-La₂O₃, was prepared by hydrothermal and immersion process using a cationic surfactant C₁₆H₃₃(CH₃)₃NBr (CTAB) as template．The samples were characterized by N₂ adsorption-desorption, X-ray diffraction(XRD), Raman spectroscope and CO₂ temperature programmed desorption(CO₂-TPD). XRD and Raman spectra indicated that the catalyst calcined at 600°C and 700 °C remained surface and bulk tetragonal phase and good mesoporous characteristics when the content of K₂O is less than 0.5. While the monoclinic phase is appeared on catalyst surface when the content of K₂O is more than 0.5 calcined at 700 °C. CO₂-TPD proves that there are two adsorption states at high temperature corresponding to super alkaline sites of K₂O and undecomposed KNO₃. The catalyst with 0.4 mol ratio of K₂O to ZrO₂ calcined at 700 °C showed higher activity in the synthesis of di-2-ethylhexyl carbonate (DEHC) from dimethyl carbonate (DMC) and 2-ethylhexanol (EHOH).

• Periodical: Advanced Materials Research (Volume 924)
• Pages: 269-274
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.924.269
• Online since: April 2014
• Authors: Yu Su, Guo Jun Dong, Cheng Yuan Wang, Jin Sheng Gao, Dong Sheng Ma, Zhi Zhong Sun, Peng Wang*
• Keywords: Mesoporous K₂O-MgO/ZrO₂-La₂O₃, Solid Base, Tetragonal Phase

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