Abstract The aim of this work was to investigate the effect of the calcination temperature on the textural properties, structure and acidity of niobium phosphate and the relationship between those properties and the catalytic activity for the continuous esterification reaction using oleic acid and ethanol. For this purpose, samples of niobium phosphate were prepared by calcination at 300, 350, 400, 450, 500 and 600 °C. Despite the good thermal stability presented by niobium phosphate, best results were achieved for samples pretreated at 300 °C, which presented higher acidity, surface area and catalytic activity. For this sample, the experimental conditions of temperature (from 220 to 290 °C), amount of catalyst (from 0 to 0.8 g) and ethanol:oleic acid molar ratio (from 2:1 to 14:1) were studied using design of experiments (DOE) and optimized with canonical analysis. The esterification reaction of oleic acid led to yields of esters up to 70% and conversion up to 90% at optimized conditions.

中文翻译：

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填充床管式反应器磷酸铌酯化反应的优化

摘要 本工作的目的是研究煅烧温度对磷酸铌结构特性、结构和酸度的影响，以及这些特性与油酸和乙醇连续酯化反应催化活性之间的关系。为此，通过在 300、350、400、450、500 和 600 °C 下煅烧制备了磷酸铌样品。尽管磷酸铌具有良好的热稳定性，但在 300 °C 下预处理的样品获得了最佳结果，具有更高的酸度、表面积和催化活性。对于该样品，实验条件为温度（从 220 到 290 °C）、催化剂用量（从 0 到 0.8 g）和乙醇：油酸摩尔比（从 2:1 到 14: 1) 使用实验设计 (DOE) 进行研究，并通过规范分析进行优化。在优化条件下，油酸的酯化反应使酯的产率高达 70%，转化率高达 90%。