Heavy oil reserves are recognized as being a significant yet challenging energy resource due to high viscosities. It is common knowledge that thermal recovery methods like in situ combustion rely on fuel deposition and oxidation to enhance oil mobility. This study explored micro and nanostructured manganese oxide catalysts to improve the efficiency of heavy oil oxidation. MnO composites were synthesized and characterized by X-ray powder diffraction (XRD), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray (EDX), Thermogravimetric analysis (TGA), and N₂ physisorption. It has been found that the smaller nanoparticles showed higher surface area (38 m²/g), oleic acid content, and mesoporosity compared to the larger microparticles which exhibited a surface area of 12.85 m²/g. Moreover, differential scanning calorimetry (DSC) analysis confirmed the catalytic activity of both particle types by intensifying oxidation peaks and lowering activation energies. However, the isoconversional calculations revealed minimal difference in oxidation times between MnO micro and nanoparticles at various conversion rates. To overcome aggregation issues, MnO nanoparticles were incorporated onto SiO₂ nanospherical particles. As a result, MnO/SiO₂ composites exhibited increased surface area and pore volume. Most importantly, they demonstrated significantly enhanced heavy oil oxidation rates, especially at a high temperature oxidation region which is considered the main key of a successful application of in situ combustion. This work highlights the promise of nanostructured MnO catalysts to improve the efficiency and economics of thermal heavy oil recovery. Further optimization of parameters like size, morphology, and dispersion extent within the reservoir could enable these materials to stabilize the combustion front and maximize heavy oil production.

中文翻译：

---

通过原位燃烧提高重油热采收率：微米和纳米结构氧化锰催化剂的作用


由于粘度高，重油储量被认为是一种重要但具有挑战性的能源资源。众所周知，原位燃烧等热采方法依靠燃料沉积和氧化来增强石油流动性。本研究探索了微米和纳米结构的氧化锰催化剂来提高重油氧化的效率。合成了 MnO 复合材料，并通过 X 射线粉末衍射 (XRD)、扫描电子显微镜 (SEM)、能量色散 X 射线 (EDX)、热重分析 (TGA) 和 N ₂ 物理吸附进行表征。研究发现，与表面积为 12.85 m ² 纳米球形颗粒上。结果，MnO/SiO ₂ 复合材料表现出增加的表面积和孔体积。最重要的是，他们证明了重油氧化率显着提高，特别是在高温氧化区域，这被认为是原位燃烧成功应用的主要关键。这项工作凸显了纳米结构二氧化锰催化剂在提高稠油热采收效率和经济性方面的前景。 进一步优化储层内尺寸、形态和分散程度等参数可以使这些材料稳定燃烧前沿并最大限度地提高重油产量。