Biorefining of Pigeon Pea: Residue Conversion by Pyrolysis

Mari Rowena C. Tanquilut, Homer C. Genuino, Erwin Wilbers, Rossana Marie C. Amongo, Delfin C. Suministrado, Kevin F. Yaptenco, Marilyn M. Elauria, Jessie C. Elauria and Hero J. Heeres
Additional contact information
Mari Rowena C. Tanquilut: College of Resource Engineering, Automatization, and Mechanization (CREAM), Pampanga State Agricultural University, PAC, Magalang, 2011 Pampanga, Philippines
Homer C. Genuino: Department of Chemical Engineering, Engineering and Technology Institute Groningen (ENTEG), University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
Erwin Wilbers: Department of Chemical Engineering, Engineering and Technology Institute Groningen (ENTEG), University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
Rossana Marie C. Amongo: Institute of Agricultural Engineering, College of Engineering and Agro-Industrial Technology (CEAT), University of the Philippines Los Baños, 4030 Laguna, Philippines
Delfin C. Suministrado: Institute of Agricultural Engineering, College of Engineering and Agro-Industrial Technology (CEAT), University of the Philippines Los Baños, 4030 Laguna, Philippines
Kevin F. Yaptenco: Institute of Agricultural Engineering, College of Engineering and Agro-Industrial Technology (CEAT), University of the Philippines Los Baños, 4030 Laguna, Philippines
Marilyn M. Elauria: Department of Agricultural and Applied Economics, College of Economics and Management (CEM), University of the Philippines Los Baños, 4030 Laguna, Philippines
Jessie C. Elauria: Institute of Agricultural Engineering, College of Engineering and Agro-Industrial Technology (CEAT), University of the Philippines Los Baños, 4030 Laguna, Philippines
Hero J. Heeres: Department of Chemical Engineering, Engineering and Technology Institute Groningen (ENTEG), University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands

Energies, 2020, vol. 13, issue 11, 1-19

Abstract: Pyrolysis is an important technology to convert lignocellulosic biomass to a renewable liquid energy carrier known as pyrolysis oil or bio-oil. Herein we report the pyrolysis of pigeon pea wood, a widely available biomass in the Philippines, in a semi-continuous reactor at gram scale. The effects of process conditions such as temperature (400–600 °C), nitrogen flow rate (7–15 mL min −1 ) and particle size of the biomass feed (0.5–1.3 mm) on the product yields were determined. A Box-Behnken three-level, three-factor fractional factorial design was carried out to establish process-product yield relations. Of particular interest is the liquid product (bio-oil), of which the yield was shown to depend on all independent variables in a complex manner. The optimal conditions for highest bio-oil yield (54 wt.% on dry feed intake) were a temperature of 466 °C, a nitrogen flow rate of 14 mL min −1 and a particle size of 1.3 mm. Validation of the optimized conditions proved that the average ( n = 3) experimental bio-oil yield (52 wt.%) is in good agreement with the predicted value from the model. The properties of product oils were determined using various analytical techniques including gas chromatography-mass spectrometry (GC–MS), gel-permeation chromatography (GPC), nuclear magnetic resonance spectroscopy ( 13 C- and HSQC-NMR) and elemental and proximate analyses. The bio-oils were shown to have low ash content (0.2%), high heating value (29 MJ kg −1 ) and contain high value-added phenolics compounds (41%, GC peak area) as well as low molecular weight aldehydes and carboxylic acids. GPC analysis indicated the presence of a considerable amount of higher molecular weight compounds. NMR measurements showed that a large proportion of bio-oil contains aliphatic carbons (~60%), likely formed from the decomposition of (hemi)cellulose components, which are abundantly present in the starting pigeon pea wood. Subsequent preliminary scale-up pyrolysis experiments in a fluidized bed reactor (~100 g feed h −1 , 475 °C and N 2 flow rate of 1.5 L min −1 ) gave a non-optimized bio-oil yield of 44 wt.%. Further fractionation and/or processing are required to upgrade these bio-oils to biofuels and biobased chemicals.

Keywords: pigeon pea; lignocellulosic biomass; pyrolysis; bio-oil; phenolics (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2020
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.mdpi.com/1996-1073/13/11/2778/pdf (application/pdf)
https://www.mdpi.com/1996-1073/13/11/2778/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:13:y:2020:i:11:p:2778-:d:365732

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().