Abstract
Lignin is considered as a promising substitute for fossil resources, but
the efficient conversion of the lignin remains a huge challenge due to
its structural complexity and immiscibility with typical solvents.
Herein, a series of surfactant-free microemulsion reactors comprised of
octane, water and n-propanol were designed and their corresponding phase
behaviors alongside their ability to intensify oxidative
depolymerization of lignin was explored. Experimental results show that
the phenolic monomer yield improves substantially (40-500 wt.%) when
the novel microemulsion systems are employed by comparison with
processes performed in a single solvent. Detailed characterizations also
suggest that the above intensification is rationalized by the
solubilization effect of the microemulsion system, which arise as a
consequence of directional aggregation of lignin at the microemulsion
interface.