Production of phenols from lignin via depolymerization and catalytic cracking

Production of phenols from lignin was investigated using a new conversion process consisting of two reaction steps. In the first step, depolymerization of lignin was carried out in an autoclave reactor using a silica-alumina catalyst in a water/1-butanol solution. The yield of lignin-derived liquid product reached 85–88 C-mol% under the appropriate reaction conditions. In the second step, catalytic cracking of the liquid products from the first step was carried out using a fixed‐bed flow reactor over an iron oxide catalyst. With this method, total recovered fraction of phenols and the conversion of methoxy phenol reached 6.6–8.6% and 92–94%, respectively.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Production of phenols from lignin was investigated via a two-step process. ► Depolymerization of lignin over silica-alumina was promoted using a H2O/BuOH solution. ► Reaction of the lignin-derived liquid product was carried out over an iron oxide catalyst. ► The iron oxide catalyst successfully converted phenols into phenol and cresol.