Cenospheres characterization from Indonesian coal-fired power plant fly ash and their potential utilization. Issue 5 (October 2020) - Petrus, Himawan Tri Bayu Murti
Graphical abstract: Highlights: Characterization of fly ash and cenospheres from six coal-fired power plants in Indonesia. Ash content in initial coal is well correlated with the cenospheres yield; the higher the ash content, the higher the cenospheres yield. Cenospheres yield and diameter possess a positive correlation with the concentration of SiO2 and Al2 O3 Other chemical compositions (Fe2 O3, TiO2, CaO, and MgO) have an opposite correlation with the cenospheres' yield and diameter. Abstract: This study presents the cenospheres formation based on the characteristic of the fly ash and the coal as well as the potential production of cenospheres from fly ash from six coal-fired power plants in Indonesia. For cenospheres characterization, SEM-EDS, petrography analysis, and particle analyzer distribution were applied through all samples. Coal and fly ash chemical composition were analyzed using proximate analysis and ICP-MS. Based on the characterization of cenospheres and fly ash chemical components, we correlate the concentration of SiO2, Al2 O3, SiO2 /Al2 O3, Fe2 O3, Fe2 O3 +TiO2, CaO, MgO in the fly ash with cenospheres yield and diameter. The cenospheres yield in six Indonesian coal-fired power plant fly ash is in the range of 0.04–0.16% and inline with the ash content in the initial coal. Moreover, it was found that the cenospheres yield and diameter are in positive correlation with the concentration of SiO2 and Al2 O3 in the fly ash, but they are in vice versa correlation with other chemicals. Ternary diagram of the cenospheres was made to their potential application and found that most of the cenospheres are in the ferrocalsialic.