Effect of ozonolysis pretreatment on enzymatic digestibility of sugarcane bagasse

Abstract

Bagasse was pretreated with ozone to increase the enzymatic hydrolysis extent of potentially fermentable sugars.  Through a 3×4 factorial design, this research studies the influence of operating parameters (moisture content and retention time) on ozonization pretreatment of bagasse in a fixed bed reactor under room conditions.  Enzymatic hydrolysis yields of up to 67% were obtained compared to 20% in non-ozonized bagasse.  Moisture content and retention time showed significant effect on ozonolysis.  And the most efficient conversion was obtained in 50% w/w humidity and 3.5 h retention time.  The study also revealed that smaller particle size in the raw bagasse improved the performance of ozonolysis as well.

Keywords: Sugarcane bagasse, ozonolysis, bioethanol, enzymatic hydrolysis

ity �T92�Ϲ0��pan lang=EN-US style='font-size:9.0pt;line-height:140%;mso-fareast-language:ZH-CN'> mm²/s was obtained for raw groundnut oil than 7.60 mm²/s obtained for groundnut oil ethyl ester.  At 15ºC, specific gravity of raw groundnut oil and its ethyl ester were 0.9 (1.047 times that of AGO) and 0.85 (1.012 times that of AGO) respectively and are within limit specified by international standards.  The biofuels contained lower amounts of sulphur (9.73% for groundnut oil ethyl ester and 12.8% for raw groundnut oil) than the reference AGO which was 61.8%.  Higher pour (4ºC and 3ºC) points, cloud (7ºC and 8ºC) points and flash (200ºC and >280ºC) points were obtained for groundnut oil ethyl ester and the raw groundnut oil respectively compared to -16ºC, -12ºC and 74ºC respectively obtained for AGO.  The fatty acid profile of the groundnut oil reveals 75.03% unsaturated fatty acids in the oil composition.  Groundnut oil ethyl ester was found to have better fuel quality than raw groundnut oil and it has potentials to fuel a diesel engine. 

Keywords: groundnut oil, automotive gas oil, transesterification, ethyl esters, biodiesel, fuel, diesel engine, Nigeria