Floatability of coal and pyrite

Technical Report · Sun Jul 01 04:00:00 EDT 1979

OSTI ID:5322523

Trieu-Ky, H

An experimental study was carried out to improve the froth flotation process for separating finely ground coal and pyrite. The effect on the flotability of coal and pyrite of water washing and acid cleaning, various inorganic reagents, and a wet oxidation treatment in a warm alkaline solution were studied. Precleaned bituminous coal from Iowa and pyrite isolated from this coal were used. The flotability was measured with a modified Hallimond tube microflotation cell in the presence of methyl isobutyl carbinol (MIBC), a commonly used frother. The floatability of pyrite was not affected by water washing regardless of the MIBC concentration. On the other hand, the flotability of pyrite in the presence of MIBC was affected strongly by cleaning with either cold or hot hydrochloric acid. Thus the relative recovery in the microflotation cell of hot acid washed pyrites (52%), and cold acid washed pyrites (22%) was much higher than that of unwashed pyrites (8%). Various inorganic reagents were found to depress the floatability of pyrite while not depressing the flotability of coal appreciably. The depressing effect of these inorganic reagents was more pronounced when applied to clean pyrites, and was insensitive to the concentration of the reagent as long as the concentration exceeded threshold value. In general, the extent of the depressing action of an inorganic reagent seemed to depend on its constituent anion and cation. Calcium hydroxide was found to be the most effective depressant, followed by sodium hydroxide, calcium chloride, and ferric chloride. Sodium chloride was found to be the least effective depressant for pyrites. Wet oxidation of pyrite or coal fines in a warm alkaline solution containing dissolved air was found effective in reducing the floatability of pyrite while not having much effect in the floatability of the coal.

• Research Organization: Ames Lab., IA (USA)
• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 5322523
• Report Number(s): IS-T-865; ON: DE84007371
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
013000* -- Coal
Lignite
& Peat-- Transport
Handling
& Storage
ALKALI METAL COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
CALCIUM CHLORIDES
CALCIUM COMPOUNDS
CALCIUM HALIDES
CALCIUM HYDROXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
CLEANING
COAL FINES
COAL PREPARATION
COLLOIDS
DATA
DISPERSIONS
EXPERIMENTAL DATA
FLOTATION
FOAMS
HALIDES
HALOGEN COMPOUNDS
HYDROCHLORIC ACID
HYDROGEN COMPOUNDS
HYDROXIDES
INFORMATION
INORGANIC ACIDS
IRON CHLORIDES
IRON COMPOUNDS
IRON SULFIDES
MINERALS
NUMERICAL DATA
OXIDATION
OXYGEN COMPOUNDS
PYRITE
REAGENTS
SEPARATION PROCESSES
SODIUM COMPOUNDS
SODIUM HYDROXIDES
SULFIDE MINERALS
SULFIDES
SULFUR COMPOUNDS
TRANSITION ELEMENT COMPOUNDS