Ultrafine Mineral Associations in Superhigh-Organic-Sulfur Kentucky Coals

James C. Hower, Debora Berti, Michael F. Hochella

Research output: Contribution to journalArticlepeer-review

8 Scopus citations


Two high-organic-sulfur Kentucky coals, the eastern Kentucky River Gem coal and the western Kentucky Davis coal, are examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), both including elemental analysis by energy-dispersive spectroscopy (EDS). From the SEM-EDS analysis, it is observed that the western Kentucky coal had areas with Pb and Cd in addition to the expected Fe and S and the eastern Kentucky coal had individual Fe-S-rich areas with La and Ni and with Si, Al, Cr, Ni, and Ti. TEM and selected area electron diffraction (SAED) analyses demonstrate that anglesite with a rim of Pb-bearing amorphous Fe-oxide occurs in the western Kentucky coal. Melanterite, an Fe-sulfate, with minor Al, Si, and K EDS peaks, suggests that clay minerals may be in close association with the sulfate, is also detected in the coal. A polycrystalline metal in the eastern Kentucky sample with a composition similar to stainless steel is adjacent to an Al-rich shard. Euhedral pyrite grains surrounded by kaolinite and gibbsite are detected. Overall, it is noted that element associations should not be assumed to be organic just because minerals cannot be seen with optical microscopy or with standard bulk analytical techniques, such as X-ray diffraction (XRD).

Original languageEnglish
Pages (from-to)12179-12187
Number of pages9
JournalACS Omega
Issue number9
StatePublished - Sep 30 2018

Bibliographical note

Publisher Copyright:
© 2018 American Chemical Society.

ASJC Scopus subject areas

  • General Chemistry
  • General Chemical Engineering


Dive into the research topics of 'Ultrafine Mineral Associations in Superhigh-Organic-Sulfur Kentucky Coals'. Together they form a unique fingerprint.

Cite this