Enhancement of delignification by aromatic scavangers
AIT RESEARCH SHOWCASE, May 2012ENHANCEMENT OF DELIGNIFICATION BY AROMATIC SCAVENGERS Yakindra Prasad Timilsena1*, Nicolas Brosse2 & Sudip Kumar Rakshit31Asian Institute of Technology, Pathumthani 12120,Thailand (*for correspondence: firstname.lastname@example.org)2Université de Lorraine, Laboratoire d’Etude et de Recherche sur le MAteriau Bois, Faculté des Sciences et Technologies, Bld desAiguillettes, BP 70236, 54506 Vandoeuvre-lès-Nancy cedex, France3Lakehead University, Thunder Bay, Ontario Canada P7B 5E1 Abstract ObjectiveFive different kinds of aromatic compounds • Compare the effect of different aromatics on(naphthol, o-cresol, p-cresol, hydroquinone and delignification ability of miscanthus.dihydroxy-anthraquinone) were assessed for their effecton enhancement of organosolv delignification ability of Results and discussionmiscanthus. The biomass was treated with each of thearomatic before autohydrolysis and the yield of ethanol • Ethanol organosolv lignin (EOL) yield was significantlyorganosolv lignin (EOL) and the Klason lignin content of increased (13.3% in control whereas 23.4% in p-cresolthe pulp after 2-step pretreatment were compared with treatment).the control and among the treatment. All the aromatics • Klason lignin content of the resultant pulp after 2-stepdemonstrated a significant reduction in Klason lignin pretreatment was reduced significantly (14.9% incontent of the pulp and increased EOL recovery as control whereas 3.8% in p-cresol treatment).compared to the control- naphthol, p-cresol and • ANOVA at 95% confidence level revealed significantdihydroxyanthraquinone having the equivalent effect. difference in control and treatments, however, the effect of p-cresol, naphthol and dihydroxyanthraquinone was equivalent Methodology • Path 2 in Fig. 2 shows the mechanism of scavenging the carbonium ions which resulted in enhanced delignification. 10 g ODW Miscanthus Fig. 1. Effect of aromatics on delignification Mixed with 0.4 g aromatics and soaked in 100 mL 30 acetone overnight EOL yield (% ) 25 KL (%) Yield (%) Acetone evaporation by air drying 20 15 Autohydrolysis (1500C, 8h, S/L=1:9) 10 5 OS delignification (1700C, 1h, SA=0.5%, S/L=1:8) 13.3 14.9 20.8 5.9 16.8 7.3 23.4 3.8 17.8 8.3 22 4.8 0 Control Naphthol o-Cresol p-Cresol Hydroquinone DHAq Treatments Filtration Liquid EOL phase Fig. 2. Mechanism of carbonium ion scavenging KL Pulp Path 0 Conclusion and Future Work• Aromatic compounds demonstrated significant enhancement in delignification ability of miscanthus during two step pretreatment process.• Assessment of additional aromatics for their effect on delignification of more lignocellulosic feedstocks is suggested for future work. SDCC / AIT – France Network The author is highly obliged to Prof. Sudip K. Rakshit and Prof. Nicolas Brosse for their invaluable advice during this study. Financial support from SDCC/AIT-France Network is highly appreciated.