Ethanol Upgrading Catalysis for Advanced Biofuels - A Combined Computational Experimental Study

Wass小组已经开发了几种催化剂，它们在将（生物）乙醇或甲醇/乙醇混合物转化为丁醇方面非常有效，丁醇是有价值的先进生物燃料（见参考文献1和2）。尽管这一领域取得了重大进展，但仍有几个关键的未解问题：(1)我们的催化剂的高选择性的起源是什么？(2)为什么结构非常相似的催化剂有时会生成乙酸乙酯而不是丁醇？(3)为什么有些催化剂能生成2-丁醇而不是1-丁醇？(4)为什么钌是最佳的金属？我们能在更便宜的第一行金属上开发催化剂吗？回答这些问题不仅对这项技术的发展至关重要，而且具有重要的科学意义。计算方法越来越多地与实验相结合，以确定机理和设计催化剂，本项目将使用这种强大的组合来解决这些问题。以第一行催化剂的问题为例；我们筛选了许多具有各种双齿配体的铁催化剂，这些配体与钌上成功的配体相似，但都失败了。显然，需要一种更复杂的方法，通过计算（有实验验证的支持）理解钌催化反应的关键机制步骤的能力将指导我们设计催化剂。

The Wass group have developed several catalysts that are highly effective in upgrading (bio)ethanol or methanol/ethanol mixtures to butanols, which are valuable advanced biofuels (see references 1 and 2). Despite significant advances in this field, there are still several critical unanswered questions: (1) What is the origin of the high selectivity of our catalysts? (2) Why do structurally very similar catalysts sometimes make ethyl acetate instead of butanols? (3) Why do some catalysts make 2-butanol rather than 1- butanol? (4) Why is Ru the best metal for this? Can we develop catalysts on cheaper first row metals? Answering these questions is of fundamental scientific interest as well as being crucial for the development of this technology. Increasingly, computational methods are used hand-in-hand with experiment to determine mechanism and design catalysts, and this project will use this powerful combination to address these questions. Taking the question of first row catalysts as an example; we have screened many iron catalysts with various bidentate ligands similar to those successful on ruthenium - all have failed. Clearly a more sophisticated approach is needed and the ability to understand the key mechanistic steps in the ruthenium-catalysed reaction by computation (backed up with experimental verification) will instruct us in catalysts design.