Selective production of 2-(tert-butyl)-3-methylphenol from depolymerization of enzymatic hydrolysis lignin with MoS2 catalyst
Yiming Ma, Yushuai Sang, Kai Wu, Qingfeng Liu, Hong Chen, Yongdan Li
Abstract
Low selectivity and complex product distribution are the main challenges for the utilization of lignin. Herein, the selective production of 2-(tert-butyl)-3-methylphenol (TBC), an antioxidant in the polymer industry, from depolymerization of enzymatic hydrolysis lignin (EHL) on a hydrothermally synthesized MoS2 catalyst is studied. The total aromatic monomer yield is 124.1 mg/g EHL and the selectivity of TBC is up to 40.3 wt% in methanol at 280 °C under 2 MPa H2 for 6 h. The FT-IR analysis of products reveals that MoS2 has a high activity for demethylation, dehydroxylation and alkylation, and the dimer conversions reveal that C-O and C-C bonds in EHL are broken with MoS2. The guaiacol and its derivants are identified as the intermediate for formation of TBC in EHL depolymerization according to the effect of time on product distribution and monomer conversion.