skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Aggregation and colloidal stability of fine-particle coal suspensions

Journal Article · · Environ. Sci. Technol.; (United States)
DOI:https://doi.org/10.1021/es00122a011· OSTI ID:6743961

The aggregation and colloidal stability of colloidal coal suspensions in the presence of varying concentrations of hydrogen ions, neutral salts and aluminium sulphate were investigated. Critical concentration and critical pH values for coagulation and stabilisation were determined from turbidity changes during settling following aggregation. Two colloidal suspensions of a bituminous coal representing stability extremes due to oxidation were compared. In the absence of other coagulants, vigorous oxidation lowered the isoelectric point of the coal sol from pH 5.1 to 1.1 and the pH for stabilisation from 7.5 to 2.6. The oxidised coal sol was slightly less sensitive to neutral salts. The boundaries of settling of the coal in the presence of aluminium sulphate were similar to other hydrophobic sols except for small differences in alkaline solutions.

OSTI ID:
6743961
Journal Information:
Environ. Sci. Technol.; (United States), Vol. 18:4
Country of Publication:
United States
Language:
English