Back to Search
Start Over
Process time variation and critical growth onset analysis for nanofoam formation in sucrose-based hydrothermal carbonization.
- Source :
-
Journal of Materials Science . Sep2021, Vol. 56 Issue 27, p15004-15011. 8p. 1 Color Photograph, 5 Graphs. - Publication Year :
- 2021
-
Abstract
- The paper presents a systematic study of the formation of carbon nanofoam from sucrose by hydrothermal carbonization. It is shown that for the process temperature of 150 °C, carbonization is not a gradual process but rather occurs suddenly at a specific threshold time of 4.5 h. pH value and electrical conductivity (EC) of the sucrose solution were monitored during carbonization. In the first 4.5 h prior to carbonization, the sucrose solution shows a sharp drop from pH 7.8 to pH 2 and sharp increase of EC. From this point on the values of pH and EC remain approximately constant. After the 4.5 h threshold, we examined the evolution of mass yield, density and morphology of the resulting carbon nanofoam. The yield first shows a steep increase around 4.5 h and then a further gradual increase up to 38% at 54.6 h. The mass density just after the 4.5 h threshold is 0.28 g/cm3 and decreases with process time to reach a constant value of 0.14 g/cm3, between 20 and 54.6 h. This shows that desired conditions, such as low density and high yield, are obtained with sufficient process time below 5 h. Due to the release of intermediates of the conversion reaction into the sucrose solution, both pH and EC were found to be excellent indicators for the progression of hydrothermal carbonization. [ABSTRACT FROM AUTHOR]
- Subjects :
- *HYDROTHERMAL carbonization
*SUCROSE
*ELECTRIC conductivity
*CARBONIZATION
Subjects
Details
- Language :
- English
- ISSN :
- 00222461
- Volume :
- 56
- Issue :
- 27
- Database :
- Academic Search Index
- Journal :
- Journal of Materials Science
- Publication Type :
- Academic Journal
- Accession number :
- 151333038
- Full Text :
- https://doi.org/10.1007/s10853-021-06222-4