Mechanisms for selective coalescence of coals: Fossil Energy quarterly report, 1 October 1987--31 December 1987

Technical Report · Tue Dec 01 04:00:00 EST 1987

OSTI ID:6642290

Wheelock, T D; Markuszewski, R; Fan, C W; Venkatadri, R; Labuschagne, B C.J.; Hu, Y C; Tyson, D

The overall objective is to determine the basic mechanisms which underlie a number of selective coalescence or oil agglomeration processes that have been proposed for beneficiating fine-size coal. Recent work has shown that the oil agglomeration recovery of less hydrophobic Illinois No. 6 coal is reduced by an increase on ionic strength of the suspending medium. Also the oil agglomeration recovery of iron pyrite is reduced by an increase in ionic strength and the reduction is affected by the cations present. Thus, pyrite recovery is affected increasingly by Na/sup +/, Ca/sup + +/, and Mg/sup + +/ ions in that order. To study the effect of mild surface oxidation on the oil agglomeration of Pittsburgh seam coal, a freshly ground sample of the coal was exposed to air at room temperature for one week. When agglomerated with heptane, the recovery from neutral or acidic suspensions was similar to that of untreated coal, but the recovery from basic suspensions was lower than that of untreated coal. The total sulfur content of the agglomerated product was significantly lower for the treated coal. The use of magnesium salts as selective depressants for pyrite was investigated and found to be very effective in the separation of a synthetic mixture of hydrophobic Upper Freeport coal and pyrite by oil agglomeration. However, when a magnesium salt was applied to the separation of a synthetic mixture of the less hydrophobic Illinois No. 6 coal and pyrite, both coal and pyrite were depressed. 3 refs., 12 figs., 4 tabs.

• Research Organization: Ames Lab., IA (USA)
• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 6642290
• Report Number(s): IS-4951; ON: DE89003749
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010300* -- Coal
Lignite
& Peat-- Preparation-- (1987-)
AGGLOMERATION
ALKALINE EARTH METAL COMPOUNDS
ALKANES
CALCIUM IONS
CARBONACEOUS MATERIALS
CHALCOGENIDES
CHARGED PARTICLES
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
CLEANING
COAL
COAL PREPARATION
COALESCENCE
DOCUMENT TYPES
ENERGY SOURCES
FOSSIL FUELS
FUELS
HALIDES
HALOGEN COMPOUNDS
HEPTANE
HYDROCARBONS
IONS
IRON COMPOUNDS
IRON SULFIDES
MAGNESIUM CHLORIDES
MAGNESIUM COMPOUNDS
MAGNESIUM IONS
MAGNESIUM SULFATES
MATERIALS
MINERALS
ORGANIC COMPOUNDS
OXIDATION
OXYGEN COMPOUNDS
PH VALUE
PROGRESS REPORT
PYRITE
RECOVERY
SODIUM IONS
SULFATES
SULFIDE MINERALS
SULFIDES
SULFUR COMPOUNDS
SULFUR CONTENT
SURFACE PROPERTIES
TRANSITION ELEMENT COMPOUNDS