8/2/2019 (Neem and Moringa) Bioenergy 2008

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Bioenergy: Challenges and OpportunitiesInternational Conference and Exhibition on Bioenergy

April 6th 9th 2008Universidade do Minho, Guimares, Portugal

EVALUATION OF RESIDUES OF BIODIESEL PRODUCTION FROM NEEM AND MORINGA AS FEEDSTOCKS

FOR BIOETHANOL PRODUCTION

Martn, C. 1,2*, Gulln, B. 2, Moure, A. 2, Martn, G. 3, Domnguez, H. 2 and Paraj, J.C. 2

1 Department of Chemistry and Chemical Engineering, University of Matanzas, Matanzas 44 740, Cuba.2 Department of Chemical Engineering, University of Vigo University of Vigo (Campus Ourense), 32004 Ourense,

Spain.3Estacin Experimental de Pastos y Forrajes Indio Hatuey, CP 44280, Matanzas, Cuba

*Corresponding author: carlos.martn@umcc.cu

ABSTRACT

Neem ( Azadirachta indica ) and moringa ( Moringa oleifera ) are non-edible oil seeds considered potential

substrates for biodiesel production in Cuba. Different residues, such as hulls and press cakes, are generated

during the preparation of the seeds for extraction of the oils to be used in biodiesel production. In this work,

physical and chemical characterisation of neem and moringa seeds and their fractions was performed, and dilute-

acid prehydrolysis of the hulls was assessed as pretreatment method for enzymatic hydrolysis if cellulose. It was

shown that the hulls represent 46 and 28 weight percent, respectively, of the seeds of neem and moringa. The

chemical characterisation of the hulls revealed that they are typical lignocellulosic materials that could be

considered for bioethanol production. A cellulose content of approximately 30% (w/w) was detected in the hulls of

both species, whereas xylan accounted for 24.7% in neem and 9.1% in moringa. A high concentration (4.3%) of

acetyl groups was found in neem hulls, what is favourable for their hydrolytic conversion to simple sugars. The

high protein content (15.2%) of moringa is a possitive feature for lowering the cost of nutrient supplementation in

ethanolic fermentation. The hulls were pretreated using 1.5-4.5% H 2SO 4, at a liquid-to-solid ratio of 10, at 131 oC

and during 15-240 min. The residual contents of xylan, cellulose and lignin were determined in the pretreated

hulls. Xylan was hydrolysed to a high extend in neem hulls, whereas cellulose and lignin were only marginally

affected. The same was observed for moringa hulls, although xylan hydrolysis occurred at a lower rate. The

enzymatic convertibility of cellulose was assayed in the pretreated hulls. Pretreatment led to a 6-fold increase of

cellulose conversion in neem hulls, but it was less effective for moringa hulls. The fermentation of the enzymatic

hydrolysates with Saccharomyces cerevisiae was also investigated.

Keywords: Azadirachta indica , Moringa oleifera , biodiesel, bioethanol, dilute-acid prehydrolysis, enzymatic

hydrolysis