Pyrolysis of olive cake with catalytic upgrading of volatile products

SAPO-34 and 1 mol% MeSAPO-34 (metal-modified catalysts, Me = Ni, Fe) were synthesized and tested for the catalytic pyrolysis of olive cake at 500 °C under inert conditions. The characterization of the catalysts was performed using XRD, BET, SEM, EDX, FT-IR, and TGA. MeSAPO catalysts demonstrated a chabazite cubic structure identical to the parent catalyst, with lower surface areas and particle sizes, and less water retention. The use of catalysts increased gas yield from 39 to 66% and decreased the oil yield from 39 to 10%. Biochar yield was maintained around 25%, and the solid samples showed an increase in carbonization as shown in the SEM and EDX results. Liquid GC-MS analysis indicated that SAPO was more selective towards alkane and amine products, whereas metal-modified catalysts favored the production of alkenes, acids, and phenols. Similarly, the analysis of the gas samples revealed the presence of light olefins and light oxygenated compounds which varied with the type of catalyst used.