Control of pyrite surface chemistry in physical coal cleaning
Abstract
With the development of microbubble flotation, flotation also shows considerable promise as a method for cleaning micronized coal to produce superclean and ultraclean fuels. One major goal is to use flotation, as a low-cost physical beneficiation process, to remove pyrite from coal. However, this has proven to be a difficult task because often the pyrite contained in coal can be hydrophobic and reports to the froth. Previous studies have shown that pyrite, like other sulfide minerals, undergoes mixed potential electrochemical reactions when immersed in an aqueous solution. Therefore, it is essential to understand the electrochemical behavior of pyrite in order to effectively reject pyrite from coal. In a previous report, it was shown that pyrite could be successfully rejected from several coal samples by manipulating the solution potential with reducing and oxidizing reagents. Controlling the redox potential of flotation circuits offers a novel and very promising route for coal desulfurization by depressing the pyrite during flotation without adversely affecting the natural hydrophobicity of coal. However, much more work is needed to understand the mechanisms responsible for the natural flotation and electrochemical depression of pyrite to improve the effectiveness of this technique. During this report period, new work on using amore »
- Authors:
- Publication Date:
- Research Org.:
- Virginia Center for Coal and Minerals Processing, Blacksburg, VA (United States)
- Sponsoring Org.:
- USDOE; USDOE, Washington, DC (United States)
- OSTI Identifier:
- 7273331
- Report Number(s):
- DOE/PC/89789-T11
ON: DE92040448
- DOE Contract Number:
- FG22-89PC89789
- Resource Type:
- Technical Report
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 01 COAL, LIGNITE, AND PEAT; COAL PREPARATION; FLOTATION; PYRITE; ELECTROCHEMISTRY; DEASHING; DESULFURIZATION; PROGRESS REPORT; REDOX POTENTIAL; CHEMICAL REACTIONS; CHEMISTRY; DOCUMENT TYPES; MINERALS; SEPARATION PROCESSES; SULFIDE MINERALS; 010300* - Coal, Lignite, & Peat- Preparation- (1987-); 010600 - Coal, Lignite, & Peat- Properties & Composition
Citation Formats
Luttrell, G H, Yoon, R H, and Richardson, P R. Control of pyrite surface chemistry in physical coal cleaning. United States: N. p., 1992.
Web.
Luttrell, G H, Yoon, R H, & Richardson, P R. Control of pyrite surface chemistry in physical coal cleaning. United States.
Luttrell, G H, Yoon, R H, and Richardson, P R. 1992.
"Control of pyrite surface chemistry in physical coal cleaning". United States.
@article{osti_7273331,
title = {Control of pyrite surface chemistry in physical coal cleaning},
author = {Luttrell, G H and Yoon, R H and Richardson, P R},
abstractNote = {With the development of microbubble flotation, flotation also shows considerable promise as a method for cleaning micronized coal to produce superclean and ultraclean fuels. One major goal is to use flotation, as a low-cost physical beneficiation process, to remove pyrite from coal. However, this has proven to be a difficult task because often the pyrite contained in coal can be hydrophobic and reports to the froth. Previous studies have shown that pyrite, like other sulfide minerals, undergoes mixed potential electrochemical reactions when immersed in an aqueous solution. Therefore, it is essential to understand the electrochemical behavior of pyrite in order to effectively reject pyrite from coal. In a previous report, it was shown that pyrite could be successfully rejected from several coal samples by manipulating the solution potential with reducing and oxidizing reagents. Controlling the redox potential of flotation circuits offers a novel and very promising route for coal desulfurization by depressing the pyrite during flotation without adversely affecting the natural hydrophobicity of coal. However, much more work is needed to understand the mechanisms responsible for the natural flotation and electrochemical depression of pyrite to improve the effectiveness of this technique. During this report period, new work on using a particulate bed electrolyte composed of pyrite particles was initiated so the flotation of pyrite could be determined as a function of potential without using chemical redox reagents. This technique will simultaneously provide information on the electrochemical reactions taking place on the particulate bed electrodes, the flotation response, and any dissolved species in solution that have chromophores in the ultraviolet-visible region of the spectrum.},
doi = {},
url = {https://www.osti.gov/biblio/7273331},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Jan 01 00:00:00 EST 1992},
month = {Wed Jan 01 00:00:00 EST 1992}
}