Smith Christene A, Brandi Francesco, Al-Naji Majd, Guterman Ryan
Department of Colloid Chemistry, Max Planck Institute of Colloids and Interfaces Am Mühlenberg 1 14476 Potsdam Germany
RSC Adv. 2021 Apr 28;11(26):15835-15840. doi: 10.1039/d1ra01460a. eCollection 2021 Apr 26.
Biorefinery seeks to utilize biomass waste streams as a source of chemical precursors with which to feed the chemical industry. This goal seeks to replace petroleum as the main feedstock, however this task requires the development of efficient catalysts capable of transforming substances derived from biomass into useful chemical products. In this study, we demonstrate that a highly-active iridium complex can be solid-supported and used as a low-temperature catalyst for both the decomposition of formic acid (FA) to produce hydrogen, and as a hydrogenation catalyst to produce vanillyl alcohol (VA) and 2-methoxy-4-methylphenol (MMP) from vanillin (V); a lignin-derived feedstock. These hydrogenation products are promising precursors for epoxy resins and thus demonstrate an approach for their production without the need for petroleum. In contrast to other catalysts that require temperatures exceeding 100 °C, here we accomplish this at a temperature of <50 °C in water under autogenous pressure. This approach provides an avenue towards biorefinery with lower energy demands, which is central to the decentralization and broad implementation. We found that the high activity of the iridium complex transfers to the solid-support and is capable of accelerating the rate determining step; the decomposition of FA into hydrogen and carbon dioxide. The yield of both VA and MMP can be independently tuned depending on the temperature. The simplicity of this approach expands the utility of molecular metal complexes and provides new catalyst opportunities in biorefinery.
生物炼制旨在利用生物质废物流作为化学前体的来源，为化学工业提供原料。这一目标旨在取代石油作为主要原料，然而，这项任务需要开发高效催化剂，能够将源自生物质的物质转化为有用的化学产品。在本研究中，我们证明了一种高活性铱配合物可以负载在固体上，并用作低温催化剂，既能催化甲酸（FA）分解制氢，又能作为加氢催化剂，将木质素衍生原料香草醛（V）转化为香草醇（VA）和2-甲氧基-4-甲基苯酚（MMP）。这些加氢产物是环氧树脂很有前景的前体，因此展示了一种无需石油即可生产它们的方法。与其他需要超过100°C温度的催化剂不同，在这里，我们在自生压力下于<50°C的水中实现了这一目标。这种方法为生物炼制提供了一条能源需求更低的途径，这对于分散化和广泛应用至关重要。我们发现铱配合物的高活性转移到了固体载体上，并且能够加速速率决定步骤；即FA分解为氢气和二氧化碳。VA和MMP的产率均可根据温度独立调节。这种方法的简便性扩展了分子金属配合物的用途，并为生物炼制提供了新的催化剂机会。
