Tailored Macroporous Hydrogels With Catalytic Nanoparticles for Chemical Engineering Processes

用于化学工程过程的具有催化纳米颗粒的定制大孔水凝胶

• 批准号: RGPIN-2018-04569
• 负责人: Virgilio, Nick
• 金额: $ 2.04万
• 依托单位: École Polytechnique de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=682841
• 关键词: Tailored; Macroporous; Hydrogels; Catalytic; Nanoparticles

Transition metal (gold, silver, etc.) nanoparticles (NPs) for heterogeneous catalysis have revealed a wide array of possibilities in the last 20 years. From water treatment applications (e.g. degradation of azo dyes and nitro compounds), to “greener” processes (e.g. the oxidation of alcohols, classically involving toxic compounds), and new synthesis pathways (e.g. aromatic amines for the pharmaceutical industry), NPs offer significant potential for chemical processes at mild conditions (room T and p, aqueous media). NPs come in various shapes, sizes, and compositions i.e. tunable reactivity , and are easy to synthesize. The successful integration of NPs in chemical engineering processes requires (1) preventing their agglomeration and coalescence to maintain reactivity, and (2) to design an efficient process allowing reuse and easy NPs separation.***Hydrogels can help achieve these goals since they efficiently entrap and inhibit NPs agglomeration, while allowing reactants and products diffusion to and from NPs surface due to their liquid-like diffusivity properties. However, the reactivity of hybrid gel-NPs materials is typically low due to diffusion-limited mass transfer. One way to significantly enhance mass transfer is to use macroporous hydrogels, which contain networks of interconnected pores (diam. > 50 nm, IUPAC) - the main challenges being to achieve precise control over pore size, distribution and interconnectivity, with the possibility of scaling up the fabrication process. ***Recently, we have developed a scalable method to synthesize macroporous gels from cocontinuous polymer blends, with a high level of control over the porosity features, and displaying enhanced mass transfer properties. The general goal of this program is to develop morphologically tailored, mechanically robust macroporous gels containing catalytic NPs, such as gold, at controlled loading and reactivity levels. Three specific objectives are proposed : (1) To quantify the impacts of polymer blend, porous polymer mold, and gel morphologies, on the catalytic and mechanical properties of NP-loaded macroporous gels, and to strengthen their mechanical properties; (2) to control the nucleation and growth of NPs in porous gels, to correlate their properties to reactivity and microstructure, and to extend synthesis to multicomponent/anisotropic NPs; (3) To quantify the flow properties and reaction yield in continuous flow conditions, as a function of microstructure. To realize this program, 3 PhD and 5 undergraduate student interns will be hired, working at the interface of polymer/gel processing, nanomaterials synthesis, and catalytic processes projects encompassing multiple aspects of chemical engineering. The long-term objective is to integrate these materials in continuous-flow and membrane reactors for the development of new catalytic, high performance chemical engineering processes.

在过去 20 年中，用于多相催化的过渡金属（金、银等）纳米粒子 (NP) 展现了从水处理应用（例如偶氮染料和硝基化合物的降解）到“绿色”工艺的广泛可能性。 （例如醇、传统有毒化合物的氧化）和新的合成途径（例如用于制药行业的芳香胺），纳米颗粒提供了巨大的潜力对于温和条件下的化学过程（房间 T 和 p，水介质），纳米颗粒具有各种形状、尺寸和成分，即可调节的反应性，并且易于合成。 纳米颗粒在化学工程过程中的成功整合需要 (1) 防止。它们的团聚和聚结以保持反应性，以及 (2) 设计一种允许重复使用和轻松分离 NP 的工艺。***水凝胶可以帮助实现这些目标，因为它们可以有效地捕获和抑制 NP团聚，同时由于其类似液体的扩散特性而允许反应物和产物扩散至纳米颗粒表面或从纳米颗粒表面扩散，然而，由于扩散限制的传质，混合凝胶纳米颗粒材料的反应性通常较低。的方法是使用大孔水凝胶，其中包含互连孔网络（直径 > 50 nm，IUPAC） - 主要挑战是实现对孔径、分布和互连性的精确控制，并有可能***最近，我们开发了一种可扩展的方法，用共连续聚合物共混物合成大孔凝胶，对孔隙率特征进行高度控制，并显示出增强的传质性能。的目标是开发形态定制的、机械坚固的大孔凝胶，其中含有催化纳米粒子（例如金），并在受控的负载和反应水平下提出了三个具体目标：（1）量化聚合物的影响。共混物、多孔聚合物模具和凝胶形态，对负载纳米颗粒的大孔凝胶的催化和机械性能进行研究，并增强其机械性能；（2）控制多孔凝胶中纳米颗粒的成核和生长，将其性能与反应性和微观结构，并将合成扩展到多组分/各向异性纳米粒子；（3）量化连续流动条件下的流动特性和反应产率，作为微观结构的函数。该项目将聘用 3 名博士生和 5 名本科生实习生，从事涵盖化学工程多个方面的聚合物/凝胶加工、纳米材料合成和催化过程项目的界面。用于开发新型催化、高性能化学工程工艺的流动和膜反应器。