Oxidation of n-butane to maleic anhydride in a milli-structured fixed-bed reactor

微型或微结构固定床反应器的概念应以正丁烷选择氧化为顺丁烯二酸酐为例进行研究，作为具有工业意义的强放热、多相催化反应的例子。与传统的反应器相比，由于扩散长度较短，平均温度较高，因此可以在这样的反应器中强化催化活性和选择性。与带有催化剂涂层壁的微结构反应器不同，固定床概念允许使用经过工业验证的催化材料，并允许简单地交换废催化剂。该项目的目的是通过实验和理论研究确定反应堆放大的基础。为此，将对不同几何形状的固定床和不同尺寸的催化剂颗粒进行系统的转化率、产品分布和压降测量。此外，停留时间分布的测量是必要的，以研究在低通道和催化剂颗粒直径比下可能的壁面效应。通过使用格子-玻尔兹曼方法等现代计算技术对固定床内的流动、反应和换热进行详细的数值模拟，加强了用于设计和放大的工程模型的公式。如果能够达到项目目标，计划继续该项目，目标是实现中试规模的微结构固定床。

The concept of micro- or milli-structured fixed-bed reactors shall be investigated with the selective oxidation of n-butane to maleic anhydride as an example of a strongly exothermic, heterogeneously catalyzed reaction with industrial relevance. It is expected that the process can be intensified regarding catalytic activity and selectivity in such a reactor because of lower diffusion lengths and higher average temperatures than in conventional reactors. In contrast to micro-structured reactors with catalyst coated walls, the fixed-bed concept allows for the use of industrially proven catalytic materials and simple exchange of spent catalysts. Aim of the project is to determine the basis for a reactor scale-up through experimental and theoretical investigations. For this purpose, systematic measurements of conversion, product distribution, and pressure drop with fixed beds of different geometries and catalyst particles with variable size will be done. Additionally, residence time distribution measurements are necessary to investigate possible wall effects at low ratios of channel and catalyst particle diameter. The formulation of engineering models for design and scale up is enhanced by detailed numerical simulations of flow, reactions and heat transfer in the fixed bed using modern computational techniques such as the lattice-Boltzmann method. If the project goal can be reached, it is planned to continue the project with the aim of realizing a milli-structured fixed-bed at pilot scale.