Sefik Tunc
I have always been interested in the research about alternative energy sources in order to reduce impact of the carbohydrates to global warming. When working on my master’s degree in pulp and paper, I started to learn more about the biorefinery process and how it uses wood more efficiently and produces alternative fuel oil to fossil fuel (petroleum). After getting my master’s degree, I decided to study in the field of wood biorefinery.
My Research
Wood, the most abundant renewable raw materials on earth, primarily consists of cellulose, hemicelluloses and lignin with minor amounts of extractives and ash. The objective during chemical wood pulping is to retain the polysaccharides while removing the lignin. Approximately 20% of the dry weight of the wood is consumed during Kraft pulping process as hemicelluloses. The degraded hemicelluloses in the waste pulping liquor are then combusted during the Kraft recovery process. However, the heating value of wood carbohydrates ( about 13.6MJ/kg) is only about half of that lignin. Therefore, a more economical use of the hemicelluloses would be to extract them prior to pulping, and then convert them to higher value-added products such as ethanol, itaconic acid and other chemicals. . In order to maintain a high pulp yield as well as the integrity of cellulose in the cooked pulp, a fundamental understanding of the kinetics of hemicellulose removal during the extractive treatment is required. The objective of this study is to investigate the influence of the operation conditions such as temperature and time on the extraction yield of hemicelluloses from mixed southern hardwood by using hot water. A (modified) Dionex ASE-100 (Accelerated Solvent Extraction Equipment) was utilized at elevated pressures to extract hemicelluloses from wood. The compositions of the extract, as well as solid phase, remained after extraction were determined by HPAEC and HPLC analysis.
In Other Words
As a result of global warming, carbon dioxide emission released from fossil fuels has big impact on accumulation of emissions gas in the atmosphere. For this reason, alternative energy sources have to be found in order to reduce, or at least keep control the existent emission. Wood is the most abundant renewable raw material on earth, and it is a potential source for production of the alternative fuel oil. Since wood is renewable, it does not contribute the existence carbon dioxide emissions in the atmosphere. The wood mainly consist cellulose, hemicellulose and lignin. The main objective during pulp production iis to liberate cellulose fibers in the wood by removing the lignin. However about 20 % of the wood weight also ends up in the waste water during the pulping process. However hemicelluloses are the important chemicals for production of fuel oil from wood. For this reason, we are trying to remove hemicelluloses from wood prior pulping by water extraction which is a environmentally friendly process. The hemicelluloses extracted from wood will be used to produce fuel oil (ethanol) and other chemicals (such as itaconic acid).
Contact Information
5737 Jenness Hall , Room 302
University of Maine
Orono, ME 04469
E-mail: sefik.tunc@umit.maine.edu