New catalyst to create chemical building blocks from biomass
Selective hydrogenolysis of carbon–oxygen bonds
Graduate School of Engineering / Faculty of Engineering
The chemical industry currently depends on fossil resources such as oil for raw materials. However, given that fossil resources are finite in quantity, alternative sources of raw materials for chemical products are required. Plant matter, and in particular inedible plant matter, is the leading candidate for such a renewable source and is the focus of much research. Such resources are collectively referred to as biomass, but a variety of problems need to be resolved before biomass can replace fossil resources as raw material for the chemical industry.
Professor Kyoko Nozaki and Assistant Professor Shuhei Kusumoto, in the University of Tokyo Graduate School of Engineering Department of Chemistry and Biotechnology, have developed a new catalyst and succeeded in selective cleaving (hydrogenolysis) of carbon-oxygen single bonds in lignin, a major component of biomass. Lignin is polymer contained in large quantities in woody biomass, but was known to be difficult to convert into useful raw materials for the chemical industry because of its complex chemical structure. In this latest research, the researchers developed a new iridium catalyst and succeeded in using hydrogen to (1) deoxygenate phenols and (2) remove methyl groups from aromatic ethers.
With conventional catalysts, the problem was that lignin aromatic rings would react with hydrogen first. This does not occur with the new catalyst and it is possible to cut only the carbon-oxygen single bond. The key characteristic of the newly developed iridium catalyst is that the ligand (hydroxycyclopentadienyl) and the metal (iridium) work cooperatively.
Benzene is currently the basis chemicals materials are obtained from petroleum, aromatic hydrocarbons (BTX) and phenols such as toluene, used as a means of production from biomass is expected.
This research may see application in developing the use of biomass as a source of raw materials for the chemical industry such as benzene, toluene, and xylene (BTX) and phenols, which are currently derived from fossil resources.
Direct and selective hydrogenolysis of arenols and aryl methyl ethers", Nature Communications Online Edition: 2015/2/23 (Japan time), doi: 10.1038/ncomms7296.
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