Residual lipids with high fatty acid content represent an important source of raw material for renewable biofuels. They are not suitable for the production of biodiesel via alkaline transesterification but can be converted to biodiesel via esterification. For these feedstocks, hydrodeoxygenation is suitable for producing hydrocarbons. However to limit hydrogen consumption, thermal processes are also object of studies. In these thermal processes nickel has been used in the form of supported catalysts but has not been well studied in the form of mixed oxides. This work aims at studying the Ni/Al ratio influence on the properties of unsupported mixed oxides prepared from layered double hydroxides (LDH) precursors, to evaluate their performance in the fast pyrolysis of myristic acid (MA) as a model compound of residual acidic lipids. Prepared materials had molar ratios Ni/Al = 0.3, 1 and 3. The catalysts were obtained through calcination of the precursors, and were characterized by XRD, TGA, FTIR, N₂ adsorption isotherms, TPD of NH₃ and EDX analysis. Myristic acid pyrolysis, with catalyst:MA mass ratio of 5:1, was carried out in a micropyrolyzer at 550 °C, and the products were analyzed through online GC/MS. Results show that the obtained catalysts presented a rather high surface area, important mesoporosity and NiO and NiAl₂O₄ crystalline phases. The catalysts with the highest Al content favored cracking with the production of hydrocarbons in the gasoline range, while the sample with highest Ni content favored the production of hydrocarbons in the kerosene range. The catalyst obtained with the combination of Ni/Al = 1 presented the highest surface area and acidity and the lowest NiO crystallite size, resulting in the best MA conversion (∼84 %) and deoxygenation degree. It also produced the highest yield in aromatic compounds due to the higher acidity and hydrogen transfer, compared to other catalysts. The present results confirm that catalytic reaction under pyrolysis conditions is able to identify some intrinsic properties of catalysts using model molecules as starting feed.

具有高脂肪酸含量的残留脂质代表了可再生生物燃料的重要原材料来源。它们不适合通过碱性酯交换生产生物柴油，但可以通过酯化转化为生物柴油。对于这些原料，加氢脱氧适用于生产烃类。然而，为了限制氢气消耗，热处理也是研究的对象。在这些热处理工艺中，镍以负载催化剂的形式使用，但尚未以混合氧化物的形式进行深入研究。本工作旨在研究 Ni/Al 比对由层状双氢氧化物 (LDH) 前驱体制备的无负载混合氧化物性能的影响，以评估它们在肉豆蔻酸 (MA) 作为残留酸性脂质模型化合物的快速热解中的性能.₂吸附等温线、NH _{3 的}TPD和EDX分析。肉豆蔻酸热解催化剂:MA 质量比为 5:1，在微热解器中于 550 °C 进行，产物通过在线 GC/MS 进行分析。结果表明，所得催化剂具有较高的表面积、重要的介孔率和NiO和NiAl ₂ O ₄结晶相。Al 含量最高的催化剂有利于裂解产生汽油范围内的碳氢化合物，而 Ni 含量最高的样品有利于生产煤油范围内的碳氢化合物。Ni/Al = 1 组合获得的催化剂具有最高的表面积和酸度以及最低的 NiO 微晶尺寸，导致最佳的 MA 转化率（~84%）和脱氧度。与其他催化剂相比，由于更高的酸度和氢转移，它还产生了最高的芳族化合物收率。目前的结果证实，在热解条件下的催化反应能够鉴定使用模型分子作为起始原料的催化剂的一些内在特性。