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To evaluate the potential of compost based on municipal solid waste (MSW) and 20% legume pruning under a pyrolysis process, generated products, including solids (biochar), liquids (bio-oil), and gases (non-condensable gases), through experimentation in a pilot plant with a fluidized bed reactor at 450°C and gas chromatography/mass spectrometry have been analysed. In addition, the compost kinetic behaviour by thermogravimetric analysis (TGA), using the Flynn-Wall-Ozawa (FWO) method, has been investigated. Four different reaction zones, associated with lignocellulosic materials (hemicellulose, cellulose, and lignin) with a first step for water evaporation, in TGA curve have been observed. A biochar with low stability and aromaticity, considering high and low O/C and H/C ratios, respectively, has been obtained. The obtained pyrolytic liquids contain a high concentration of phenolic compounds because of a significant presence of lignins and other high molecular weight compounds in the original material. Moreover, the generated non-condensable gases consist mainly of short-chain compounds, such as alcohols, aldehydes, and alkenes produced from hemicellulose, cellulose, and proteins., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

To ascertain the potential of various leguminous biomass such as L. leucocephala , C. proliferus , P. alba and S. sesban , both energetic and a source of high added value products, the pyrolytic behaviour was studied at different heating rates by using the analytical method of thermogravimetric (TG), isoconversional method of Kissinger-Akahira-Sunose (KAS), determination of some thermodynamic parameters and pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS). It was concluded that biomass such as L. leucocephala or C. proliferus are more suitable for pyrolysis since less energy is required to degrade them, more evident in the final stages of degradation in which P. alba and S. sesban present very high activation energies calculated by KAS. All leguminous biomass produced volatile compounds with high phenol content at the peak of maximum degradation of hemicellulose, most of the heavy derivates are derived from lignin, such as ferulaldehyde or methoxyeugenol, because sufficient energy has not yet been provided to break down the structure. At this peak it can see some furans and saccharides in the case of C. proliferus since it has a higher C 5 content in its composition. A wide range of compounds were detected at the peak of maximum degradation of cellulose, L. leucocephala and C. proliferus produce more short-chain compounds that give rise to bio-oils whereas, S. sesban and especially P. alba , in addition, produce a quantity of high added value of saccharides such as levoglucosan and d -allose (4.73% and 13.94%, respectively). [Display omitted] • Low heating rates help to understand mechanisms of reaction in pyrolysis biomass. • Leguminous biomass can produce certain amount of volatile compounds. • L. leucocephala and C. proliferus are suitable to thermochemical treatments. • P. alba and S. sesban could be adequate species to produce volatile saccharides. [ABSTRACT FROM AUTHOR]