Use of Empty Fruit Bunches from the Oil Palm for bioethanol production: A thorough comparison between dilute acid and dilute alkali pretreatment

• Published in: Bioresource technology Vol. 159; pp. 355 - 364
• Main Authors: Chiesa, S., Gnansounou, E.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.05.2014; Elsevier
• Subjects: Arecaceae - chemistry; Biofuel production; Biofuels; Biological and medical sciences; Biomass; Biotechnology; Biotechnology - methods; Dilute sodium hydroxide pretreatment; Dilute sulfuric acid treatment; Dilution; Economics; Energy; Ethanol - metabolism; Feedstock; Fruit - chemistry; Fruit - drug effects; Fruits; Fundamental and applied biological sciences. Psychology; Glucans - analysis; Glucose - metabolism; Industrial applications and implications. Economical aspects; Lignin - analysis; Lignocellulosic bioethanol; Methods. Procedures. Technologies; Microbial engineering. Fermentation and microbial culture technology; Oil Palm Empty Fruit Bunches (EFBs); Oil palm trees; Optimization; Pretreatment; Saccharification; Sodium Hydroxide - pharmacology; Sulfuric Acids - pharmacology; Surface response analysis; Xylans - analysis; Oil Palm Empty Fruit Bunches (EFBs); Surface response analysis; Lignocellulosic bioethanol; Dilute sodium hydroxide pretreatment; Dilute sulfuric acid treatment; Monocotyledones; Ethanol; Fruit; Chemical pretreatment; Biofuel; Lignocellulosics; Sulfuric acid; Sodium hydroxide; Alcoholic fermentation; Chemical treatment; Angiospermae; Basic medium; Response surface; Spermatophyta; Palmae; Elaeis guineensis; Acid medium; Oil plant (vegetal)
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2014.02.122

•Oil palm Empty Fruit Bunches shown as good candidates for bioethanol production.•Two pretreatment techniques compared (acid/alkali): the first option is superior.•Optimized dilute acid treatment (≈161°C, 10min, 1.5% acid): 85% glucose yield.•Alkali treatment is seriously hampered by high lignin content of the feedstock.•Fate of the different components of biomass monitored during each treatment. In the present work, two pretreatment techniques using either dilute acid (H2SO4) or dilute alkali (NaOH) have been compared for producing bioethanol from Empty Fruit Bunches (EFBs) from oil palm tree, a relevant feedstock for tropical countries. Treatments’ performances under different conditions have been assessed and statistically optimized with respect to the response upon standardized enzymatic saccharification. The dilute acid treatment performed at optimal conditions (161.5°C, 9.44min and 1.51% acid loading) gave 85.5% glucose yield, comparable to those of other commonly investigated feedstocks. Besides, the possibility of using fibers instead of finely ground biomass may be of economic interest. Oppositely, treatment with dilute alkali has shown lower performances under the conditions explored, most likely given the relatively significant lignin content, suggesting that the use of stronger alkali regime (with the associated drawbacks) is unavoidable to improve the performance of this treatment.