Catalytic conversion of CO2 and biomass-derived phenols to high-value chemicals

英国已成为世界上第一个提出到2050年将所有温室气体排放量降至净零的主要经济体。该研究项目将致力于利用二氧化碳，这是制药和精细化学品以及不断发展的生物塑料工业的化学中间体生产中最普遍和最有效的温室气体。通过催化偶联生物质衍生的酚类化合物来生产高价值的化学品，如芳香族羧酸（ACA），这将是一条很有前途的新途径。如果成功的话，这个项目将是一个双赢的可持续发展和全球努力，以减轻气候变化和全球变暖。简而言之，有完善的协议制备羧酸，然而，最直接的方法获得羧酸是通过直接羧化[1]。唯一众所周知的羧化反应是Kolbe-Schmitt反应，由于高温和高压要求，它有自己的缺点[2]。Sadamitsu等人（2019）设法在环境条件下使用间苯二酚（一种酚类化合物）并添加有机碱合成相应的水杨酸来实现Kolbe-Schmitt反应。然而，这种类型的反应需要非常长的停留时间并且限于一种特定的酚类化合物，这限制了生物质衍生的酚类化合物的使用。此外，添加有机碱需要额外的分离阶段，这在更大规模上可能成本高昂且效率低下。尽管自最初的报道以来已经过去了一个半世纪，但还没有关于酚类的有效羧化的方法的报道。自1957年以来，仅对原始报告进行了改进和修改[2]。该研究项目的独特之处在于，它不仅关注CO2的催化转化，而且通过探索从生物质中获得酚类化合物的选择来进一步减少碳足迹。将探索的路线是，（1）从生物质热解油中分离酚类和（2）从木质素的水热液化（HTL）中生产酚类。使用生物油的唯一障碍是由于非常广泛的产品分布而导致的分离[4]。因此，开发选择性催化剂在缩小产品分布方面起着重要作用，从而能够从生物质中更高产率地分离酚类。通过减少二氧化碳和在生物油生产中使用绿色原料来生产高附加值化学品的高效内部生产过程最终将允许商业化。该研究项目旨在通过引入优化的替代生产系统来改变19世纪世纪的发现。虽然连续加工有能力生产更安全和更可持续的工艺，但大多数制造商仍然依赖于批量生产。实验结果将用于模拟和设计一个连续钻机。Dessimoz等人（2012年）使用微型装置在高压和高温下进行了Kolbe-Schmitt反应的连续反应-强调由于高质量和热传递性能而有效控制工艺参数的适用性。微毛细管具有大规模生产的局限性，因此需要将混合与流体速度和压力解耦的连续技术。这些将在本项目中详细探讨。参考文献[1] X. Wu等人，最高Curr ^P.P. 1-60，2018年。[2]J. Luo等人，Chem. - A Eur. J.，第22卷，第20期，第120页。6798-6802，2016。[3]Y.定光等等人，Chem.Commun.，第55卷，第66期，第100页。9837-9840，2019年。[4]Y. Elkasabi，SN应用et.al Sci.，第2卷，第3期，第100页。2020年1-9月。

The UK has become the first major economy in the world proposing to bring all greenhouse gas emissions to net-zero by 2050. This research project will be dedicated to utilise CO2, the most ubiquitous and potent greenhouse gas in the production of chemical intermediaries for pharmaceuticals and fine chemicals as well as the growing bioplastic industry. A new promising route to produce high value chemicals such as aromatic carboxylic acids (ACAs) via catalytic coupling of biomass derived phenols will be explored. If successful, this project will be a win-win for sustainable development and for the global efforts to mitigate climate change and global warming.In brief, there are well-established protocols for the preparation of carboxylic acids, however, the most straight forward method for accessing carboxylic acids is through direct carboxylation [1]. The only well-known carboxylation reaction is the Kolbe-Schmitt reaction and it has its own set-backs due to high temperature and pressure requirements [2]. Sadamitsu et al. (2019) managed to achieve the Kolbe-Schmitt reaction at ambient conditions using resorcinol (a phenolic compound) with the addition of an organic base to synthesis the corresponding salicylic acid. However, this type of reaction requires very long residence time and is limited to one specific phenolic compound which restricts the use of biomass derived phenolic compounds. Moreover, the addition of an organic base requires an additional separation stage which can be costly and inefficient at a larger scale. Even though one and a half centuries have passed since the original report, no method has been reported for an efficient carboxylation of phenols. Efforts have only been made for improvement and modification of the original report since 1957 [2]. What makes this research project unique is that it does not focus only on catalytic conversion of CO2, but to further reduce carbon footprint through exploring the options of obtaining phenolic compounds from biomass. The routes that will be explored are, (1) isolation of phenols from biomass pyrolysis oils and (2) production of phenols from hydrothermal liquefaction (HTL) of lignin. The only stumbling block in the use of bio-oils is their separation due to very wide product distributions [4]. Therefore, developing selective catalyst plays an important role in narrowing production distribution, consequently, enables higher yield separation of phenols from biomass. An efficient in-house production process of value-added chemicals through reducing CO2 and the use of green feedstock in production of bio-oil will ultimately allow commercialisation.This research project aims to revolutionise the growth of the 19th century finding by introducing an optimised alternative production system to the conventional batch process. While continuous processing has the ability to produce safer and more sustainable processes, most manufacturers still rely on batch production. Experimental results from this project will be used to simulate and design a continuous rig. Dessimoz et al. (2012) carried out continuous reaction of the Kolbe-Schmitt reaction under high pressure and temperature using a micro-plant - emphasising on the suitability for efficient control of process parameters due to high mass and heat transfer performance. Micro-capillaries have the limitations of large-scale productions, hence continuous technologies that decouple mixing from the fluid velocities and pressures are required. These will be explored in detail in this project.References[1] X. Wu et al.,Top Curr. Chemis, pp. 1-60, 2018.[2] J. Luo, et al., Chem. - A Eur. J., vol. 22, no. 20, pp. 6798-6802, 2016.[3] Y. Sadamitsu et. al, Chem. Commun., vol. 55, no. 66, pp. 9837-9840, 2019.[4] Y. Elkasabi, SN Appl. et.al Sci., vol. 2, no. 3, pp. 1-9, 2020.