Gaseous phase surface modification of coal

Technical Report · Mon Jan 01 00:00:00 EST 1990

DOI:https://doi.org/10.2172/6677992· OSTI ID:6677992

Pinion, J; Okoh, J M

The enhancement of the surface hydrophobicity of coal is essential in coal cleaning processes such as froth flotation or selective agglomeration. Friedel-Crafts reaction results in the formation of alkyl groups on the coal surface. Using various chemical reagents (alkenes, alcohols and catalyst) the surface hydrophobicity of the coal was enhanced. Comparative surface studies using treated and untreated coal showed as increase in the contact angle of untreated coal form 41{degrees} originally to 74{degrees} after treatment. The effects of the chemical treatment on the coal surface was subsequently confirmed in flotation tests. Using Illinois {number sign}6 coal, floatability was increased from 28.91% to 72.15% in 18 seconds, while the work of adhesion was decreased from 91.80 to 71.97 Joule/m{sup 2}. Enhanced hydrophobicity is correlated with the degree of coal surface alkylation. 7 figs.

• Research Organization: Maryland Univ., College Park, MD (USA)
• Sponsoring Organization: DOE/FE
• DOE Contract Number: FG22-88PC88926
• OSTI ID: 6677992
• Report Number(s): DOE/PC/88926-T3; ON: DE90016761
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
COAL
SURFACE PROPERTIES
ADHESION
ALKYLATION
CORRELATIONS
FLOTATION
FRIEDEL-CRAFTS REACTION
MODIFICATIONS
PROGRESS REPORT
SURFACES
WETTABILITY
CARBONACEOUS MATERIALS
CHEMICAL REACTIONS
DOCUMENT TYPES
ENERGY SOURCES
FOSSIL FUELS
FUELS
MATERIALS
SEPARATION PROCESSES
010600* - Coal
Lignite
& Peat- Properties & Composition
010300 - Coal
Lignite
& Peat- Preparation- (1987-)