Characterization of syngas and bio-char: Co-products from pyrolysis of waste fish fats

Waste fish fats from Tunisian fish industry were pyrolyzed under nitrogen in a laboratory scale fixed-bed reactor. The pyrolysis was performed with a heating rate of 5°C/min from the ambient up to a final temperature of 500°C. In these conditions the main product is bio-oil (55 wt.%) while the co-products are syngas (44 wt.%) and bio-char (1 wt.%). The objective of this work is to characterize syngas and bio-char, to improve this technology in environmental and economic terms. The bio-char is characterized using elemental analysis (CHNS), moisture content, Fourier Transform Infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analyses furthermore the syngas composition is determined during the pyrolysis reaction. From the obtained results, we can conclude that the characterization of the pyrolysis by-products indicate that: (i) The syngas contains CH, CO₂, CO and H₂S; (ii) The bio-char characterization by elemental analyses indicates a high oxygen content and a moderate carbon content; these properties are confirmed by a high proportion of oxygenated functions and a modest aliphaticity (FTIR analyses).