We report the effect of Co incorporation into a SiO₂–Al₂O₃ supported catalytic system on the conversion, selectivity, and stability for the catalytic conversion of methyl oleate into diesel grade hydrocarbons with systematic changes in reaction parameters including temperature, time and hydrogen pressure. A series of cobalt loaded (4–12 wt%) SiO₂–Al₂O₃ catalysts were prepared by a simple wet impregnation method. The formation of a Co₃O₄ active catalyst phase and its homogenous dispersion on the SiO₂–Al₂O₃ surface is revealed successively by XRD and TEM. The results showed that the formation of a Co₃O₄ phase over CoO/Co, the amount of Co loading, reaction time, temperature and H₂ pressure greatly determine the conversion and selectivity. Total ester conversions with more than 50% selectivity towards n-heptadecane/n-octadecene were achieved at a temperature as low as 280 °C and 15 bar H₂ pressure within 10 h using a 6% cobalt loaded catalyst. Significant hydrocracking was observed at higher metal loading under similar reaction conditions.

中文翻译：

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油酸甲酯催化转化为碳氢化合物：SiO2-Al2O3中钴氧化物物种整合的影响

我们报告了Co掺入SiO ₂ -Al ₂ O ₃负载的催化体系中对油酸甲酯催化转化为柴油级烃的转化率，选择性和稳定性的影响，其中反应参数包括温度，时间和氢的系统变化压力。通过简单的湿法浸渍法制备了一系列负载钴（4-12 wt％）的SiO ₂ -Al ₂ O ₃催化剂。Co ₃ O ₄活性催化剂相的形成及其在SiO ₂ -Al ₂ O ₃上的均匀分散XRD和TEM相继揭示了表面。结果表明，在CoO / Co上形成Co ₃ O ₄相，Co负载量，反应时间，温度和H ₂压力极大地决定了转化率和选择性。使用6％钴负载的催化剂，在低至280°C的温度和15 bar H _2的压力下，在10小时内可获得对正十七烷/正十八烯选择性超过50％的总酯转化率。在相似的反应条件下，在较高的金属负载下观察到明显的加氢裂化。