Chemical characterization of organic components in leachates from coal
Laboratory leaching experiments were conducted using coals collected immediately after being received at an electrical generating facility or from mines located in western Maryland and central Pennsylvania. Leaching conditions were selected to: (1) determine the effects of different environmental storage conditions on the organic content of coal leachate, (2) determine whether release of organic material is the result of direct microbial attack, chemical alteration of the organic matrix of the coal or both, and (3) examine the effect of coal weathering on the organic content of coal leachate. Organic components associated with the particle and soluble fractions of coal leachate were solvent extracted, fractionated using silica gel chromatography, and characterized with GC/FID and GC/MS techniques. Soluble polymeric material released from coal (MW > 500 AMU) was isolated with Amberlite XAD-2 resin. Leachates from coal were found to have low pH, high concentrations of suspended particulate material and high conductivities. Solvent extracts of the soluble and particle fractions of the leachates contained complex mixtures of aliphatic and aromatic hydrocarbons including alkyl-substituted and normal polynuclear aromatic hydrocarbons. PAH from coal storage can contribute as much as 4% of the total PAH mass loading to areas adjacent to coal storage piles. Aliphatic hydrocarbon content of coal leachates was influenced by the presence of heterotrophic bacteria and was more susceptible to weathering than the aromatic hydrocarbon fraction. Infrared and UV spectra and oxidation products of the isolated polymeric material suggest the polymeric material was highly aromatic with oxygen substitution.
- Research Organization:
- Maryland Univ., College Park (USA)
- OSTI ID:
- 6986910
- Country of Publication:
- United States
- Language:
- English
Similar Records
Implications to the aquatic environment of polynuclear aromatic hydrocarbons liberated from Western Great Plains coal. Final report 30 Jun 75-1 Jul 78
Chemical and microbiological factors influencing the leaching of trace metals and trace organics from coal. Final report