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

将以正丁烷选择性氧化为顺丁烯二酸酐作为强放热、非均相催化反应的工业相关性实例，研究微米或毫米结构固定床反应器的概念。预期在这种反应器中，由于比常规反应器更低的扩散长度和更高的平均温度，该方法的催化活性和选择性可以得到增强。与具有催化剂涂覆壁的微结构反应器相比，固定床概念允许使用工业上证明有效的催化材料和简单的废催化剂交换。该项目的目的是通过实验和理论研究确定反应器放大的基础。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转化率、产物分布和压降的系统测量。此外，停留时间分布的测量是必要的，以调查可能的壁效应在低比例的通道和催化剂颗粒直径。用于设计和按比例放大的工程模型的制定通过使用现代计算技术（如格子-玻尔兹曼方法）对固定床中的流动、反应和传热进行详细的数值模拟来增强。如果项目目标能够实现，计划继续该项目，以实现中试规模的毫微结构固定床。

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.