DESIGNING GOLD CATALYSTS FOR THE UTILISATION OF BIO-RENEWABLE FEEDSTOCKS

本提案旨在寻找一类新的重要催化剂用于绿色氧化过程。特别是，我们将研究多相催化剂，其中反应物和生成物与催化剂处于不同的相。多相催化在英国经济中扮演着重要的角色，因为它本质上涉及从药品到电子设备的大多数成品的制造。催化是绿色技术的基石；然而，我们的大多数燃料和制成品的原料，如油漆和聚合物，都来自碳氢化合物的化石储备。最近，人们对英国生活方式对这些碳氢化合物原料的可用性和价格可能发生的变化的潜在敏感性产生了相当大的兴趣。对于英国来说，随着经济上可行的北海石油储量正在下降，英国将严重依赖进口能源和化工原料，这种情况变得越来越严重。在这种背景下，目前有一项举措是增加生物柴油的利用，生物柴油是由甲醇与植物油反应产生的。目前，允许在普通柴油中添加5%的生物柴油，但预计这一比例将会增加。不幸的是，生物柴油生产提供了大量的甘油作为副产品，目前还没有大规模使用。这可能会限制生物柴油的使用。因此甘油作为一种生物可再生原料广泛使用，其潜在的绿色用途尚未开发。此外，还有一系列以碳水化合物形式提供的生物可再生原料。该研究项目的目的是设计选择性氧化催化剂，可用于氧化各种底物，并为在新的绿色技术中有效利用这些生物可再生原料提供基础。目前迫切需要这种方法，因为即使在今天，许多非绿色方法目前正在提倡选择性氧化。该提案的核心是卡迪夫大学申请者的研究小组最近的发现，支持金-钯纳米颗粒是氢氧化为过氧化氢的特别有效的催化剂，以及醇氧化为醛的转换频率比之前报道的这一重要反应的最佳催化剂高25倍。我们现在寻求扩大这些催化剂可以有效的反应范围，并以这种方式为特定功能的选择性氧化反应提供工具箱。这种方法有两个预期的结果。首先，我们的目标是设计出可以在实验室中作为标准合成方法使用的金催化剂。其次，我们的目标是证明这些催化剂也可以用于氧化更复杂的生物可再生原料，如糖和萜烯。目前，我们已经在高压釜反应器中进行了实验，这适合我们最初的目标，即建立作为标准实验室试剂的负载金催化剂；我们将使用发现催化和化学工程相结合的方法来评估连续过程的选择。

This proposal seeks to find a new class of important catalysts for use in green oxidation processes. In particular, we will study heterogeneous catalysts, where the reactants and products are in a different phase from the catalyst. Heterogeneous catalysis plays an important role in the well being of the UK economy since it is inherently involved in the manufacture of most finished products from pharmaceuticals to electrical devices. Catalysis is a cornerstone of green technology; however, most of our fuels and feedstocks for manufactured goods such as paints and polymers come from fossil reserves of hydrocarbons. Considerable interest has recently been focussed on the potential sensitivity of the lifestyle within the UK to the possible variation in the availability and price of these hydrocarbon feedstocks. This is becoming increasingly acute for the UK as stocks of economically viable North Sea oil are now declining and the UK will be heavily dependent on imported energy and chemical feedstocks. Against this background there is a current move to increase the utilisation of bio-diesel which is derived from the reaction of methanol with vegetable oils. At present it is permissible to add 5% of bio-diesel to commercial diesel, but this is expected to increase. Unfortunately, bio-diesel production provides large quantities of glycerol as a by-product, for which there is no current large scale use. This is potentially limiting for the take up of biodiesel. Hence glycerol is widely available as a bio-renewable feedstock for which potential green uses have yet to be developed. In addition, there is a range of bio-renewable feedstocks available in the form of carbohydrates. The aim of this research project is to design selective oxidation catalysts that can be used for the oxidation of a wide range of substrates and in addition provide the basis for the efficient utilisation of these bio-renewable feedstocks in new green technologies. Such an approach is desperately needed at present as, even today, many non-green approaches are currently being advocated for selective oxidation. At the heart of this proposal lies the recent discoveries, in the research group of the applicants at Cardiff, that supported gold-palladium nanoparticles are exceptionally effective catalysts for the oxidation of hydrogen to hydrogen peroxide, and the oxidation of alcohols to aldehydes with turnover frequencies >25 times higher than the previously reported best catalysts for this important reaction. We now seek to extend the range of reactions for which these catalysts can be effective and in this way provide a toolbox for selective oxidation reaction of specific functionalities. This approach has two intended outcomes. The first is that we aim to design gold catalysts that can be used in the laboratory as a standard synthetic methodology. In the second, we aim to show that these catalysts can be used also for the oxidation of the significantly more complex bio-renewable feedstocks such as sugars and terpenes. At present we have conducted experiments in autoclave reactors, which are suitable for our initial aim to establish supported gold catalysts as a standard laboratory reagent; we will use a combined discovery catalysis and chemical engineering approach to evaluate options for continuous processes.