Surface properties of photo-oxidized bituminous coals. Technical progress report for the period April to June, 1996
During this report period, two vitrinite concentrates were prepared and analyzed from the hvBb Ohio No. 4a and hvAb Lower Kittanning seams. Results show that concentrates of 97 and 96 vol% vitrinite were achieved for the respective samples. Both samples have relatively high concentrations of sulfate sulfur which is the only sign of deterioration. However, in the case of the Lower Kittanning sample the sulfate may have been part of the original sample. Irradiation (photo-oxidation) of all six vitrinite concentrates for three different time periods (10, 50 and 100 min) using a ultraviolet lamp was continued during this report period. Evaluation showed that these irradiation times provided a level of photo-oxidation that corresponded to the blue-light flux used in the optical microscope system for 1, 5 and 10 min irradiations, respectively. From evaluation of the surface luminescence of vitrain surfaces following exposure to UV light the authors have determined the intensity decreases with increasing irradiation time. Film flotation results, although incomplete, show that there is some variability in flotation yield as a function of rank and of photo-oxidation time. As observed from contact angle and FTIR spectral measurements on polished surfaces, the hvCb Illinois No. 6 powdered vitrain shows a significant loss in flotation yield with increasing irradiation time following 10 and 50 min of exposure to UV light. Also, a relative minor change in flotation yield was observed for the mvb Splash Dam vitrain powder after 10 and 50 min irradiation. The Splash Dam vitrain gave a slight increase in flotation yield suggesting that the surface became somewhat more hydrophobic. Results from the hvAb Lower Kittanning sample appear intermediate. A significant increase in flotation yield occurs after 10 min irradiation marked by a relatively large decrease after 50 min.
- Research Organization:
- Dept. of Energy, Washington, DC (United States)
- Sponsoring Organization:
- USDOE Assistant Secretary for Fossil Energy, Washington, DC (United States)
- DOE Contract Number:
- FG22-93PC93223
- OSTI ID:
- 650112
- Report Number(s):
- DOE/PC/93223-T10; ON: DE97054028; TRN: AHC2DT04%%23
- Resource Relation:
- Other Information: PBD: Aug 1996
- Country of Publication:
- United States
- Language:
- English
Similar Records
Surface properties of photo-oxidized bituminous coals. Technical progress report, July--September 1995
Surface properties of photo-oxidized bituminous coals. Technical progress report, April 1995--June 1995