Abstract

A novel synthetic approach is proposed to the production of macroporous magnetic iron oxides and their iron aluminate composites for liquid-phase catalytic oxidation. The materials were prepared by sol–gel synthesis where metal precursors were mixed with a colloidal template solution based on siloxane–acrylate latex. The pore structure and magnetic properties of the composites were studied as functions of temperature and magnetic field. The effects of the heat treatment schedule on the phase composition, porosity, and catalytic properties of the materials were elucidated. The results are supported by scanning electron microscopy, X-ray powder diffraction analysis, nuclear gamma resonance, and low-temperature nitrogen adsorption. The addition of aluminum ions in the course of sol–gel (template) synthesis allows the materials to preserve their pore structure upon high-temperature treatment, thereby improving the catalytic properties and significantly affecting the magnetic characteristics of the resulting magnetic composites.

中文翻译：

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液相催化氧化大孔磁性氧化铁及其复合材料

摘要

提出了一种新颖的合成方法来生产用于液相催化氧化的大孔磁性氧化铁及其铝酸铁复合材料。这些材料是通过溶胶-凝胶合成法制备的，其中金属前体与基于硅氧烷-丙烯酸酯胶乳的胶体模板溶液混合。研究了复合材料的孔结构和磁性能随温度和磁场的变化。阐明了热处理程序对材料的相组成，孔隙率和催化性能的影响。结果得到了扫描电子显微镜，X射线粉末衍射分析，核γ共振和低温氮吸附的支持。