Direct determination of organic oxygen in coal

Abstract

This study has been achieved to establish the direct determination method of oxygen content of organic compounds in coal. The recommended procedure was as follows. The thermal decomposition of a known amount of sample is dealed with two stage system and evolved volatile matter is pyrolyzed completely in thermal decomposing zone heated to keep 1100 °C. Carbon dioxide in occured gas is reduced to CO in PtEC zone of 900 °C. Produced gas is collected into Tedlar bag and then introduced to gas-meter by tubingpump and the sample gas is taken periodically by autosampler through this process to measure con-. centration of CO by gas chromatography. Experimental results showed that it was suitable to determine the calibration value with anthraquinone and an thracene. The observed value of anthracene was coincident to intercept of calibration curve with anthraquinone. The chip of silica tube was used as filler of thermal decomposing zone of 1100 °C. In the case of porcelain material with porosity, adsorption of CO gas was observed. And the correction about the oxygen of inorganic compounds in ash could be disregarded. The observed values of oxygen content of organic compounds in coal by this method are good coincident to the calculated values based on the difference subtracted the analytical values of elements and ash from 100(%). The precision of analytical value is good and the coefficient of variation is 2 %. The time required of each analysis by this method is 20 minutes. © 1985, The Japan Society for Analytical Chemistry. All rights reserved.