Laboratory of Bioproduct Chemistry, Center of Innovative and Applied Bioprocessing (CIAB), Sector 81(Knowledge City), Mohali, 140306, Punjab (India.
ChemSusChem. 2022 Sep 7;15(17):e202200902. doi: 10.1002/cssc.202200902. Epub 2022 Jul 20.
The present study focused on developing a stable basic MnOx support for Ru (RuMn) for the efficient oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) in water in the absence of an external base. A series of MnOx supports, synthesized via hydrothermal approach using urea as precipitant, was prepared by thermal treatment at various temperatures (300-800 °C) before doping with Ru. The RuMn-2 (1 wt % Ru, MnOx calcined at 400 °C) possessed a large number of basic sites (1.72 mmol g ) based on CO temperature-programmed desorption analysis, affording an FDCA yield of 87 % with a turnover frequency of 22 h . Transmission electron microscopy energy-dispersive X-ray spectroscopy elemental mapping of RuMn-2 showed a high dispersion of Ru over the surface of MnOx, contributing to the efficient HMF oxidation. Moreover, X-ray diffraction, X-ray photoelectron spectroscopy, and H temperature-programmed reduction indicated that the predominant MnO phase (ϵ-MnO ) played a vital role in HMF oxidation. RuMn-2 was recyclable for up to four runs without significant loss in the activity and retained its structural integrity.
本研究旨在开发一种稳定的基础 MnOx 负载 Ru（RuMn），用于在无外加碱的条件下，将 5-羟甲基糠醛（HMF）高效氧化为 2,5-呋喃二甲酸（FDCA）。通过水热法使用尿素作为沉淀剂合成了一系列 MnOx 载体，然后在不同温度（300-800°C）下进行热处理，再掺杂 Ru。RuMn-2（1wt%Ru，在 400°C 下煅烧的 MnOx）在 CO 程序升温脱附分析中具有大量的碱性位（1.72mmol g ），提供了 87%的 FDCA 产率和 22 h 的转化率频率。RuMn-2 的透射电子显微镜能量色散 X 射线光谱元素映射显示，Ru 在 MnOx 表面高度分散，有助于高效的 HMF 氧化。此外，X 射线衍射、X 射线光电子能谱和 H 程序升温还原表明，主要的 MnO 相（ϵ-MnO ）在 HMF 氧化中起着至关重要的作用。RuMn-2 可重复使用多达 4 次，活性没有明显损失，并保持其结构完整性。
