Microwave-Assisted Lignin Conversion to Liquid Products in the Presence of Iron and Nickel

Results of the microwave-assisted catalytic pyrolysis of lignin have been described. It has been shown that, in a medium of an inert gas (argon) and a hydrogen–argon mixture, the following maximum liquid yield is achieved: 33 and 36% for iron-containing catalyst samples and 45% for nickel-containing catalysts. The gas chromatography–mass spectrometry (GC/MS) method has been used to determine the qualitative composition of the liquid product fraction, which is mostly represented by phenol and anisol, i.e., derivatives of the monomeric units of lignin (coumaryl and coniferyl alcohols). Probable sites of interaction of the functional groups of the lignin surface with nanosized particles of nickel- and iron-containing catalysts have been studied by IR spectroscopy.