Continuous Flow Manufacturing of Catalytic Nanomaterials

传统上，纳米级催化剂是通过不提供对催化剂结构的精确控制的方法制备的。胶体路线提供了对纳米颗粒尺寸、形状、组成和结构的改进控制。纳米颗粒通常通过在用于稳定它们并影响它们的形状和结构的封端配体的存在下用合适的还原剂还原金属盐或络合物来合成。基础合成包括反应物络合物形成、反应物形态形成、成核、生长、聚集的各个步骤。这些步骤对反应条件（浓度、pH和温度）敏感，其均匀性受到流体力学、质量和热传递的影响。这使得这种方法在分批容器中的可扩展性具有挑战性，因为这些条件可能是不均匀的并且受到反应容器尺寸的影响。连续毫流反应器提供了一种技术，该技术可以精确控制颗粒特性，同时能够提高纳米颗粒合成的再现性和鲁棒性。该研究项目旨在研究用于制造催化纳米颗粒的毫流体方法。不同的流动反应器将进行研究，以促进纳米粒子的合成，减少污垢和控制的混合条件。纳米颗粒将负载在典型的载体上，如氧化铝、二氧化钛、二氧化硅，并应用于与药物或合成燃料相关的催化反应。

Nanoscale catalysts have traditionally been prepared by methods that do not provide accurate control on the catalyst structure. Colloidal routes offer improved control on nanoparticle size, shape, composition and structure. The nanoparticles are synthesised typically by the reduction of a metal salt or complex with a suitable reducing agent in the presence of capping ligands that are used to stabilise them and affect their shape and structure. The underlying synthesis consists of various steps of reactant complex formation, reactant speciation, nucleation, growth, aggregation. These steps are sensitive to reaction conditions (concentrations, pH, and temperature), whose uniformity is influenced by hydrodynamics, mass and heat transfer. This makes the scalability of such processes in batch vessels challenging, as these conditions can be nonuniform and affected by reaction vessel size. Continuous millifluidic reactors offer a technology, which can allow precise control of particle characteristics, while at the same time enable improved nanoparticle synthesis reproducibility and robustness. This research project aims to investigate millifluidic approaches for manufacturing catalytic nanoparticles. Different flow reactors will be studied to facilitate nanoparticle synthesis with reduced fouling and control of the mixing conditions. The nanoparticles will be supported on typical supports such as alumina, titania, silica and applied to catalytic reactions of relevance to pharmaceuticals or synthetic fuels.