Pyrolysis of extractive rich agroindustrial residues

• Pyrolysis of extractive rich residues (cashew nut shells, jatropha and shea cakes).
• Extractives have no significant influence on pyrolysis of biomass macromolecules.
• Interactions between different decomposition products happen to minor extent.
• CNSL is not entirely cracked and can be recovered in pyrolysis oils.
• Triglycerides extractives are thermo-chemically decomposed during pyrolysis process.

The sub-Saharan region of West Africa has a lack of natural resources, especially for energy producing. Agroalimentary biomasses like residues from nut processing and vegetable oil producing industries are so far unexploited concerning their potential application as fuel. This study explores the usability of cashew nut shells, jatropha and shea nut presscakes in energetic terms. In contrast to lignocellulosic biomass these residues are rich in extractives. The feedstocks were characterised in a first step upon their physical and chemical properties before they were pyrolysed in a thermogravimetric system and a tubular reactor under rapid pyrolysis conditions. This approach revealed the influence of extractives on decomposition behaviour and conversion. A detailed study of obtained pyrolysis oils showed that the extractives of cashew nut shells are not entirely cracked while vegetable oils decompose almost entirely. Jatropha oil is more unstable than shea butter. Rubber wood was chosen as a reference feedstock for further comparison with extractive rich biomasses.