• Analytical Science and Technology
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• v.24 no.6
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• pp.503-509
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• 2011

Specific surface area is becoming a very important factor when newly developed advanced nano-materials are evaluated. But there have been many differences in results when measuring specific surface areas, depending on the measuring equipments and analysis method. To verify the reliability of the specific surface area measurement device supplied within the country, Round Robin Test (RRT) has been done at 21 affiliated research institutes. As a result, it was found that several institute had problems in measuring of gas adsorption amount in measuring equipment, and this proved the need for certified reference material (CRM). Furthermore, it was also found that the results from BET analysis is easily swayed by the analyst's subjectivism, and the calculated results may differ up to 16% in case of CRM I depending on the selection range of BET analysis. So this showed that a standard guideline for BET constant C value and fitting correlation coefficient R is needed, to properly select range in BET analysis. The experience in RRT, distribution of CRM, and standardized procedure would result in improved reliability in industrial processes, and thus, would contribute to the quality management, the productivity improvement, the safety evaluation, and the new material development.

• Journal of Korea Foresty Energy
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• v.21 no.2
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• pp.1-9
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• 2002

Pine bark was carbonized by using a small-scale experimental kiln and three different types of large-scale kilns (simple (400-$500^{\circ}C$), improved (600-$700^{\circ}C$) and special kiln (800-$1,000^{\circ}C$). The physical properties and pore structures of the bark charcoals prepared were analyzed. When the bark was carbonized at various temperatures ranging from 500 to $900^{\circ}C$in the presence of nitrogen, carbonization yield decreased rapidly with increasing carbonization temperature and it remained constant from 700 to $900^{\circ}C$. The carbonization yield of the bark was 16 - 18% higher than that of pine wood. The BET specific surface areas and iodine values increased with a decrease in carbonization yield. The BET specific surface areas of the bark charcoals reached about 400 -$500m^2／g$ for carbonization yield of 32-40%. The pine wood charcoal prepared at $600^{\circ}C$ for 30 min resulted in a more microporous structure, whereas the bark charcoal prepared at the same condition was more mesoporous. The carbonization yields and physical properties such as iodine values and BET specific surface areas of bark charcoals prepared by using the large-scale kilns were very similar to those of the small-scale kiln. The results indicated that the pine bark could be used as starting material to produce good quality charcoal having a large specific surface area and a high carbonization yield.