Catalytic pyrolysis of mandarin residue from the mandarin juice processing industry

In this study, the catalytic pyrolysis of mandarin residue from the mandarin juice processing industry was carried out using pyrolysis gas chromatography/mass spectroscopy and employing microporous zeolite catalysts, HZSM-5 (SiO2/Al2O3 = 23 and 80) and HBeta (SiO2/Al2O3 = 25). The effect of acidity of the catalyst was investigated by comparing the activity of two HZSM-5 catalysts with different SiO2/Al2O3 ratios. The effect of catalyst structure was explored by comparing the results obtained using HZSM-5 (23) and HBeta. Most oxygenates produced from non-catalytic pyrolysis were removed by catalytic upgrading, whereas the yields of mono-aromatics, which are important feedstock materials for the chemical industry, increased considerably, improving the quality of the bio-oil produced. HZSM-5 (23), having the highest acidity among the catalysts used in this study, showed superior catalytic activity to those of HZSM-5 (80) and HBeta. Pt/HZSM-5 (23) and Ga/HZSM-5 (23) resulted in an even higher yield of aromatics.