Comparative study of bio-oils obtained by fast and slow pyrolysis of peach stone

ABSTRACT

The processing of pickled peaches generates the peach stone as an agro-industrial residue that is difficult to dispose of. Thus, the woody endocarp pyrolysis technique is an efficient treatment for converting biomass into value-added products. Among the products, bio-oil is composed of two immiscible phases (organic and aqueous), with potential to supply the production of chemical products in different industrial sectors. The objective of this study was to obtain and evaluate the constitution of the organic phase of the bio-oils based on the fast (quartz reactor) and slow (stainless steel reactor) pyrolysis of the woody endocarp, both with fixed bed at 700°C, thus evidencing the influence of processes in the constitution of the obtained bio-oils. As liquid fractions, they were derived with N-methyl-N-trimethylsilyltrifluoracetamide for further characterization in gas chromatography coupled with mass spectrometry. Through the methodology employed, a total of 59 and 41 compounds were detected in the organic phases of the fast and slow pyrolysis bio-oils, respectively; Phenols are the majority, with 59.9 and 67.2% by weight, where the methoxyphenol (fast) and cresols (slow) are the predominant compounds. It is concluded that the derivatization stage and the gas chromatography/mass spectrometry technique were satisfactory for the qualitative and semi-quantitative characterization of bio-oils, which they can potentially use as a source of chemical products and to benefit from reuse of residue.

bio-oil; pyrolysis; agroindustrial residue