Divided solids -powders and granules- in reactive and non-reactive environments

提出的研究是关于催化活性颗粒系统的研究。一种新获得专利的多相催化剂，使用零值冶金残渣作为活性载体，有望开发有关催化机理的新知识，并由此衍生出可用于工业应用的新系列催化配方。拟进行的研究重点如下：***1。开发新的多相催化剂家族：这项工作有助于开发新的低成本催化配方，既适用于已知的工艺，也适用于工业生产水平的新工艺。建议配方中的关键成分是Rio-Tinto-Fer - titanium采矿渣（升级段塞氧化物- UGSO）；正如我们之前的工作所证明的那样，UGSO可以作为尖晶石结构生产的基础；此外，其组分（主要是MgO/Al2O3/Fe2O3）也可以作为催化剂或与其他金属、混合氧化物或氧化物溶液结合使用。以往的研究表明，Ni-UGSO催化剂可以有效地用于任何类型的碳氢化合物和含氧化合物的重整和部分氧化。氧化和还原反应是环境和绿色化学工程驱动的反应体系的重要步骤。***2。将催化活性与三相边界联系起来：就纳米形态在多相催化中的作用的机理理解而言，缺少的元素之一是在三相边界（即TPB）和催化活性之间建立联系。除了开发可用于工业应用的新型催化配方外，主要的科学创新在于适应FIB断层扫描/扫描电镜成像分析，直接计算TPB长度并将其与催化剂活性联系起来。主要的挑战/新颖之处在于找到一种协议，允许在不影响催化剂完整性的情况下，在TOS上进行足够的图像对比度和采样。多相反应器设计空间定义与建模：多相反应器是多步骤过程的典型例子。它们的特点是串联和并联动量，传热和传质（在多孔催化剂的情况下包括外部和内部）和表面反应阻力。尽管考虑到所有这些步骤的模型是理想的，并且产生了漂亮的确定性模型，但必须做出许多假设。后者通常无法通过实验检验，因此这些模型的适用性有限。本研究提出筛选变量，允许定义一个设计空间，其中表面反应成为控制步骤。在这种情况下，建模，无论是随机的还是现象学的，都变得更加容易和成功。

The proposed research regards the study of catalytically active particulate systems. A newly patented heterogeneous catalyst, using a zero-value metallurgical residue as active support, promises the development of new knowledge on catalysis mechanisms and the therefrom derived possibility of creating a new family of catalytic formulations for industrial applications. The intended research focuses on the following:***1. Development of a new family of heterogeneous catalysts: This work contributes into the development of new low-cost catalytic formulations applied both to already well known processes and to novel ones which would be used at industrial production level. The key-component in the proposed formulations is the Rio-Tinto-Fer & Titane mining residue (UpGraded Slug Oxide – UGSO); UGSO, as demonstrated in our previous work, can be used as the basis for the production of spinel structures; moreover, its components (mainly MgO/Al2O3/Fe2O3) can also be used as such or associated with other metals, mixed-oxides or oxides solutions in catalytic formulations. The previous works have shown that the Ni-UGSO catalyst can be used efficiently in any type of hydrocarbons and oxygenates reforming and partial oxidation. The proposed research targets oxidation and reduction reactions, both of which are important steps in environmentally and green chemical engineering-driven reactive systems.***2. Link catalytic activity with triple phase boundary: One of the missing elements in terms of mechanistic understanding of the role of nanomorphology in heterogeneous catalysis is the establishment of a link between the triple-phase-boundary (i.e. TPB) and catalytic activity. Besides the development of novel catalytic formulations, which could find industrial applications, the main scientific novelty resides in the adaptation of the FIB tomography/SEM imaging analysis to calculate directly the TPB length and relate it to the catalysts activity. The main challenge/novelty is to find the protocol allowing for sufficient image contrast and sampling over TOS without affecting catalysts integrity.***3. Multi-phase reactors design space definition and modeling: Multiphase reactors are typical examples of multi-step processes. They are characterized by in-series and parallel momentum, heat and mass transfer (both external and internal in the case of porous catalysts) and surface reaction resistances. Although models taking into account all these steps are desirable and yield nice-looking deterministic models, many assumptions must be made. The latter cannot be, usually, tested experimentally and consequently these models have only limited applicability. This research proposes the screening of variables allowing the definition of a design space where surface reaction becomes the controlling step. In that case modeling, both stochastic and phenomenological, becomes easier and more successful.