Key Lab. of Biomass Energy and Material, Jiangsu Province, National Engineering Lab. for Biomass Chemical Utilization; Key and Open Lab. on Forest Chemical Engineering, Institute of Chemical Industry of Forest Products, Chinese Academy of Forestry, SFA, Nanjing 210042, China.
Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China.
Molecules. 2020 Apr 30;25(9):2109. doi: 10.3390/molecules25092109.
It is of great importance to explore the selective hydrogenolysis of β--4 linkages, which account for 45-60% of all linkages in native lignin, to produce valued-added chemicals and fuels from biomass employing UV light as catalyst. TiO exhibited satisfactory catalytic performances in various photochemical reactions, due to its versatile advantages involving high catalytic activity, low cost and non-toxicity. In this work, 20 wt.% Ni/TiO and oxidant PCC (Pyridinium chlorochromate) were employed to promote the cleavage of β--4 alcohol to obtain high value chemicals under UV irradiation at room temperature. The Ni/TiO photocatalyst can be magnetically recovered and efficiently reused in the following four consecutive recycling tests in the cleavage of β--4 ether bond in lignin. Mechanism studies suggested that the oxidation of β--4 alcohol to β--4 ketone by oxidant PCC first occurred during the reaction, and was followed by the photocatalysis of the obtained β--4 ketone to corresponding acetophenone and phenol derivates. Furthermore, the system was tested on a variety of lignin model substrates containing β--4 linkage for the generation of fragmentation products in good to excellent results.
探索选择性氢解β-4 键（占天然木质素所有键的 45-60%）以利用紫外线作为催化剂从生物质生产高附加值化学品和燃料非常重要。TiO 由于其多功能优势，包括高催化活性、低成本和无毒，在各种光化学反应中表现出令人满意的催化性能。在这项工作中，使用 20wt%的 Ni/TiO 和氧化剂 PCC（吡啶氯铬酸盐）在室温下的紫外线照射下促进β-4 醇的裂解，以获得高价值的化学品。Ni/TiO 光催化剂可以通过磁回收，并在随后的四次连续循环测试中有效地重复用于木质素β-4 醚键的裂解。机理研究表明，氧化剂 PCC 首先将β-4 醇氧化为β-4 酮，然后得到的β-4 酮在光催化作用下生成相应的苯乙酮和苯酚衍生物。此外，该体系还在多种含有β-4 键的木质素模型底物上进行了测试，以获得良好至优异的断链产物。
