Production of biofuels, limonene and pectin from citrus wastes
Artikel i vetenskaplig tidskrift, 2010

Production of ethanol, biogas, pectin and limonene from citrus wastes (CWs) by an integrated process was investigated. CWs were hydrolyzed by dilute-acid process in a pilot plant reactor equipped with an explosive drainage. Hydrolysis variables including temperature and residence time were optimized by applying a central composite rotatable experimental design (CCRD). The best sugar yield (0.41 g/g of the total dry CWs) was obtained by dilute-acid hydrolysis at 150 degrees C and 6 min residence time. At this condition, high solubilization of pectin present in the CWs was obtained, and 77.6% of total pectin content of CWs could be recovered by solvent recovery. Degree of esterification and ash content of produced pectin were 63.7% and 4.23%, respectively. In addition, the limonene of the CWs was effectively removed through flashing of the hydrolyzates into an expansion tank. The sugars present in the hydrolyzates were converted to ethanol using baker's yeast, while an ethanol yield of 0.43 g/g of the fermentable sugars was obtained. Then, the stillage and the remaining solid materials of the hydrolyzed CWs were anaerobically digested to obtain biogas. In summary, one ton of CWs with 20% dry weight resulted in 39.641 ethanol, 45 m(3) methane, 8.91 limonene, and 38.8 kg pectin.

orange

by-products

Citrus waste

Ethanol

fermentation

extraction

peel

Biogas

Pectin

ethanol

Limonene

saccharomyces-cerevisiae

saccharification

dilute-acid hydrolysis

Författare

Mohammad Pour Bafrani

Chalmers, Kemi- och bioteknik, Kemisk reaktionsteknik

Gergely Forgács

Chalmers, Kemi- och bioteknik, Kemisk reaktionsteknik

Ilona Sárvári Horváth

Högskolan i Borås

Claes Niklasson

Chalmers, Kemi- och bioteknik, Kemisk reaktionsteknik

Mohammad Taherzadeh Esfahani

Högskolan i Borås

Bioresource Technology

0960-8524 (ISSN)

Vol. 101 11 4246-4250

Ämneskategorier

Industriell bioteknik

Kemiteknik

Kemi

DOI

10.1016/j.biortech.2010.01.077

PubMed

20149643