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采用四种不同的方法制备了系列铁酸铁超微粒子催化剂，考察了其对乙苯和环己烷的氧化脱氢反应性能．结果表明，（Ｄ）样品具有最佳的乙苯氧化脱氢反应活性：４００℃，Ｏ２／Ｃ６Ｈ５Ｃ２Ｈ５（ｍｏｌ）＝３．０时，乙苯转化率为５０％，苯乙烯选择性为８０％，苯乙烯单收达４０％．催化剂对乙苯氧化脱氢反应的活性随样品的粒径变小而提高，对环己烷氧化脱氢反应则恰好相反，即活性随粒径变小而降低．这种差别归因于反应物分子结构与催化剂表面原子配位结构的匹配作用．ＥＳＲ结果对比表明，粒径小的粒子的原子配位结构对称性较低．
A series of iron ferrite ultrafine particles catalysts were prepared by four different methods and the oxidative dehydrogenation of ethylbenzene and cyclohexane was investigated. The results showed that (D) the sample had the best oxidative dehydrogenation activity of ethylbenzene: 400 ℃, O2 / C6H5C2H5 (mol) = 3.0, the conversion of ethylbenzene was 50%, the selectivity of styrene was 80% Styrene up to 40%. The activity of the catalyst for the oxidative dehydrogenation of ethylbenzene increases as the particle size of the sample becomes smaller, but the opposite of the oxidative dehydrogenation of cyclohexane, ie the activity decreases as the particle size becomes smaller. This difference is due to the match between the molecular structure of the reactants and the atomic coordination structure of the catalyst surface. The comparison of ESR results shows that the symmetry of the atomic coordination structure of particles with small particle size is low.