High Quality Bio-Oil Production from Catalytic Microwave-Assisted Pyrolysis of Pine Sawdust

The catalytic microwave-assisted pyrolysis of pine sawdust using SiC and Ni modified HZSM-5 as microwave absorbent and catalyst for high quality bio-oil production was investigated. The Ni modified HZSM-5 catalyst was successfully prepared through the co-precipitation method and further characterized by X-ray diffraction (XRD) and surface area and pore size analyses. The product yield results showed that Ni modified HZSM-5 catalyst decreased the bio-oil yield and increased the gas yield. Gas chromatography-mass spectrometry (GC-MS) analysis showed that the bio-oil mainly contained alcohols, aldehydes, ketones, carboxylic acids, furans, and phenolics. The Ni modified HZSM-5 catalyst dramatically decreased the carboxylic acids and ketones content, while it remarkably increased phenolics, especially the phenol content. The physical property analysis showed that the bio-oil with the Ni modified HZSM-5 catalyst had a higher calorific value. Therefore, under microwave-assisted pyrolysis conditions, Ni modified HZSM-5 catalyst had a remarkable effect for improving the quality of bio-oil.