We measured the non-carbon content of single-walled carbon nanotubes (SWCNTs) in SWCNT soot using thermogravimetric analysis. The weight increased percentage by the oxidation of metal in the raw soot is well obtained by TGA graph which was confirmed with ICP-AES, XRD, and XPS. This work will be very useful for the purity precise evaluation of SWCNT with UN-vis-NIR spectroscopy.
PVC핏치의 제조 조건에 따른 물성 변화 및 산화 안정화에 영향을 미치는 공정 변수를 연구하기 위하여 열중량 분석을 하였다. 산소 분위기를 사용하여 안정화온도, 승온속도 및 가스의 유량을 변화시켜 조사하였다. 안정화 온도가 높아짐에 따라 무게증가를 나타내는 시간구간이 짧아지고 결합되는 산소의 양은 감소하는 경향을 나타내며, 290˚C정도로 안정화 온도가 높은 경우에는 결합되는 산소의양이 최대점에 도달한 후 다시 감소하는 경향을 나타냈다. 승온속도가 빨라짐에 따라 결합되는 산소의양은 감소하는 경향을 나타내었으나, 가스의 유량은 본 연구에서 설정한 범위 내에서는 영향이 관찰되지 않았다. 핏치 입자 직경이 커짐에 따라 최대 무게증가 값은 감소하고 최대 무게증가를 나타내는 온도는 증가함을 알았다. 그리고, 안정화에 의한 무게증가가 클수록 PVC핏치의 탄소수율은 감소하는 경향이 나타났다.
Thermogravimetric analysis (TGA) is a thermal analysis technique that the mass of sample is measured by time and temperature changes. In this study, TGA was applied for estimating the proportion of Nylon-6,6 nanofibers in the cement paste as well as the decomposition temperature of Nylon-6,6 nanofibers. An electrospinning process was conducted for producing nanofibers and adding directly into the cement powder. The TGA results show that there was approximately 0.5 % of nanofibers in the composite pastes. Besides, the decomposition temperature of Nylon-6,6 nanofibers was clarified in the range of 300℃ to 410℃.
Biomass as a renewable energy source has several limitations in terms of the potential for steady supply and its thermal characteristics. This study conducted a thermal weight change analysis and determined its kinetics to address this problem. Sawdust was chosen as the biomass, and PE and PP were the plastics used. Based on the result of thermogravimetric analysis (TGA), the kinetic characteristics were analyzed using Kissinger, Ozawa, and Friedman methods, which are the most common methods used to obtain reaction coefficients and activation energy. The methods used to determine the thermal degradation kinetics were considered feasible for evaluating the pyrolytic behavior of the materials tested. The experimental results of this study provided insights into mixed biomass/plastics pyrolysis kinetics and their optimal operation conditions.
There is an increasing demand for sustainable resources due to a steady increase in energy demand. As the1996 Protocol to the London Convention takes effect, conversion of sewage sludge to energy is increasing. To use waste as fuel, it is important to understand its combustion characteristics. Using thermogravimetric analysis, the combustion of coal, dried sewage sludge, and SRF was characterized in this study. Dried sludge and SRF showed similar combustion behavior at all temperature increase rates of 5, 10, 25, 40, and 100oC/min. Coal burned at a higher temperature as the temperature rate increased. This may be ascribed to the much higher volatile matter contents of dried sludge and SRF comparative to coal.