Preparation of Syringaldehyde from Lignin by Catalytic Oxidation of Perovskite-Type Oxides.

ABSTRACT

The influence of different reaction conditions on the yield of syringaldehyde was studied by using perovskite oxide as the catalyst. The optimal reaction conditions are as follows 0.60 g of dealkali lignin, 0.60 g of 5 wt % theta ring-loaded LaFe0.2Cu0.8O3 catalyst, 30 mL of 1.0 mol/L NaOH solution, 160 °C reaction temperature, 0.80 MPa O2 pressure, and 2.5 h reaction time. Under these conditions, the highest syringaldehyde yield was 10.00%. The recycling performance of the catalyst was studied. It was found by XRD analysis that the catalyst maintained high catalytic activity after four times of use.