New Manufacturing Processes for More Sustainable Commodity Chemicals

化学工业生产的一些最简单但最重要的化学品是用复杂的间接方法生产的。许多从天然气中提取的化学物质都是通过一种被称为“合成气”的中间体合成的，它是一氧化碳和氢气的混合物。从合成气中生产化学品是非常成熟的，许多工艺已经运行了几十年。然而，合成气的生产需要高压（30atm）和非常高的温度（800℃及以上）。生产合成气的恶劣条件需要昂贵的制造设备和浪费25%的天然气原料来产生反应所需的高温。从天然气中生产化学品的另一种途径是使用在较低温度下工作的催化剂，这种催化剂能够选择性地氧化天然气中的碳氢化合物。天然气的直接转化将使这种宝贵的自然资源得到更可持续和更有效的利用。然而，尽管选择性氧化催化研究取得了进展，但由于与基于合成气的路线相比，整体性能较差，因此没有工业实践的直接天然气转化工艺投入使用。这通常是由于催化剂倾向于过度氧化碳氢化合物，导致大量二氧化碳的形成。将天然气直接转化为化学品的发展也将为伴生天然气（与石油联合生产的天然气）的燃烧提供一种替代办法- -估计每年燃烧1 430亿立方米的天然气，其数量超过科威特的天然气产量。这项研究的目标是为甲烷和乙烷（天然气的主要成分）的部分氧化开发新的选择性氧化催化剂和新的制造工艺，以更可持续地生产必需的商品化学品。本研究中使用的催化剂将以沸石为基础，沸石是从可持续的、富含土壤的材料中提取出来的，作为绿色催化剂已经广泛应用于化学工业。这项研究金的方案将修改沸石，形成可以选择性地将碳氢化合物氧化为有价值的化学产品的新材料。研究的一个关键方面是了解催化剂的结构如何影响反应的结果，因为这将使结构-功能关系的发展，使改进催化剂的发展成为可能。失活过程和催化剂寿命，工业催化剂发展的关键方面，将探讨，以确保工业相关性。

The production of some of the simplest but most important chemicals manufactured by the chemical industry are made in complicated, indirect ways. Many chemicals derived from natural gas are synthesised through an intermediate known as "synthesis gas", a mixture of carbon monoxide and hydrogen. The production of chemicals from synthesis gas is extremely well established and many processes have been operating for several decades. However, the production of synthesis gas requires high pressures (30 atm) and very high temperatures (800 C and above). The aggressive conditions used for the production of synthesis gas require expensive manufacturing plants and waste 25% of the natural gas feedstock to generate the high temperatures required for the reaction. An alternative route to produce chemicals from natural gas would be to employ catalysts that operate at lower temperature and are able to selectively oxidise the hydrocarbons present in natural gas. The direct conversion of natural gas would enable more sustainable and efficient utilisation of this valuable natural resource. However, despite progress in selective oxidation catalysis research, no industrially practised direct natural gas conversion process is in operation due to the overall poor performance compared to synthesis gas based routes. This is commonly due to the fact that the catalysts tend to over oxidise the hydrocarbons, resulting in the formation of large quantities of carbon dioxide. The development of direct natural gas conversion to chemicals would also provide an alternative to the flaring of associated natural gas (gas co-produced with oil) - it is estimated that 143 billion cubic metres of natural gas are flared per year, a quantity greater than the natural gas production of Kuwait. The goal of this research is to develop new, selective oxidation catalysts and new manufacturing processes for the partial oxidation of methane and ethane (the principle components of natural gas) for more sustainable production of essential, commodity chemicals. The catalysts utilised in this research will be based on zeolites, which are derived from sustainable, earth abundant materials and are already widely used in the chemical industry as green catalysts. The programme of this fellowship will modify zeolites to form new materials that can selectively oxidise hydrocarbons to valuable chemical products. A key aspect of the research is understanding how the structure of the catalysts affects the outcome of reaction, as this will enable the development of structure - function relationships, enabling the development of improved catalysts. Deactivation processes and catalyst lifetime, key aspects of industrial catalyst development, will be explored to ensure industrial relevance.