Enhanced production of 4-ethyl phenol from activated carbon catalyzed fast pyrolysis of bagasse with 9,10-dihydroanthracene as a hydrogen donor

A novel way was put forward with 9,10-dihydroanthracene (DHA) as a solid hydrogen donor to improve the selective production of 4-ethyl phenol (4-EP) from catalytic fast pyrolysis (CFP) of bagasse over activated carbon (AC) catalyst. Both pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and lab-scale CFP experiments were carried out on the 4-EP formation affected by various factors, in order to determine the optimal conditions for 4-EP production. The results indicated that DHA exhibited promising hydrogenation capabilities to improve 4-EP formation. In Py-GC/MS test, the 4-EP reached a maximal yield of 3.21 wt% with its corresponding selectivity of 22.96 % at 350 degrees C under AC-to-bagasse (AC-to-BA) and DHA-to-bagasse (DHA-to-BA) ratios of 6:1 and 1:5, respectively. Whereas, the maximal 4-EP yield was only 2.18 wt% in the absence of DHA, indicating a yield increase of 47.2 % by DHA. Moreover, lab-scale experiments attained the highest 4-EP yield and the corresponding selectivity of 3.05 wt% and 16.31 % with DHA, compared with the yield of 1.67 wt% without DHA. In addition, the possible hydrogenation mechanism of DHA in facilitating 4-EP formation was revealed.