School of Chemical and Energy Engineering, Universiti Teknologi Malaysia, 81310 UTM Johor Bahru, Johor, Malaysia.
Chemical and Petroleum Engineering Department, UAE University, P.O. Box 15551, Al Ain, United Arab Emirates.
Sci Total Environ. 2022 Nov 1;845:157206. doi: 10.1016/j.scitotenv.2022.157206. Epub 2022 Jul 8.
In efforts to achieve a sustainable development goal, the utilization of CO to generate renewable fuels is promising, as it is a sustainable technology that provides affordable and clean energy. To realize the production of renewable green fuels, a proficient and low-cost technology is required. Using photo/thermal catalytic process, the goal of sustainable CO hydrogenation can be achieved. There have been several types of catalysts under exploration, however, they are expensive with limited availability. In the current development, green materials such as mineral clays are emerging as cocatalyst/supports for CO hydrogenation. Clays are bestowed with various beneficial properties such as a large surface area, high porosity, abundant basic sites, excellent thermal stability and chemical corrosion resistance. Clays are promising materials that can drastically reduce the cost in catalyst preparation, partially fulfil the energy demand and reduce greenhouse gas emission. This review aims to focus on the various types of clays and their applications in the field of photo/thermal CO hydrogenation to renewable fuels. Firstly, the classifications of clays are provided, whereby they can be differentiated based on their silicate layers, namely 1:1 and 2:1 type clay and their properties are thoroughly discussed to provide advantages and applications. The applications of various clays such as kaolinite, halloysite, montmorillonite, attapulgite, saponite and volkonskoite for CO hydrogenation reactions are systematically discoursed. In addition, various approaches to improve the capability of raw clays as catalyst support are critically discussed, which include thermal treatment, exfoliation, acid-leaching and pillaring approaches. A critical discussion regarding the engineering aspects to further enhance clay-based catalyst for CO hydrogenation are further disclosed. In short, clays are freely available materials that can be found in abundance. However, there are many more different types of natural green clays that have not been studied and explored in various energy applications.
为了实现可持续发展目标，利用 CO 来生成可再生燃料具有广阔的前景，因为它是一种可持续的技术，可以提供经济实惠且清洁的能源。为了实现可再生绿色燃料的生产，需要一种高效且低成本的技术。利用光/热催化过程，可以实现可持续的 CO 加氢目标。已经有几种类型的催化剂在探索中，但它们昂贵且可用性有限。在当前的发展中，矿物粘土等绿色材料作为 CO 加氢的共催化剂/载体正在出现。粘土具有多种有益的特性，如大表面积、高孔隙率、丰富的碱性位、优异的热稳定性和耐化学腐蚀性。粘土是一种很有前途的材料，可以大大降低催化剂制备成本，部分满足能源需求并减少温室气体排放。本综述旨在重点关注各种类型的粘土及其在光/热 CO 加氢制可再生燃料领域的应用。首先，提供了粘土的分类，根据其硅酸盐层，可以将其分为 1:1 和 2:1 型粘土，并对其性质进行了深入讨论，以提供优势和应用。系统地论述了高岭石、埃洛石、蒙脱石、凹凸棒石、皂石和绿坡缕石等各种粘土在 CO 加氢反应中的应用。此外，还批判性地讨论了提高原始粘土作为催化剂载体性能的各种方法，包括热处理、剥离、酸浸和柱撑方法。进一步公开了关于进一步提高基于粘土的 CO 加氢催化剂工程方面的关键讨论。简而言之，粘土是可自由获得的材料，并且可以大量存在。然而，还有许多其他类型的天然绿色粘土尚未在各种能源应用中进行研究和探索。
