Using electrophoresis in modeling sulfate, selenite, and phosphate adsorption onto goethite

Journal Article · Sat Jun 01 00:00:00 EDT 1985 · Environ. Sci. Technol.; (United States)

DOI:https://doi.org/10.1021/es00136a010· OSTI ID:5255421

Hansmann, D D; Anderson, M A

The authors evaluate methods for determining two quantities generally considered necessary in modeling adsorption. First, the electrical component of net binding constants is determined by electrophoresis in conjunction with pH measurement. Second, three techniques for determining the maximum concentration of available surface sites are compared. The authors use a Stern model to make out evaluations; however, the results should be applicable to adsorption modeling in general. Electrophoretic mobility data are modeled quite successfully, but the empirical determined maximum surface-site concentration on colloidal goethite (..cap alpha..-FeOOH) varies considerably for sulfate, selenite, and phosphate despite their similar sizes and binding mechanisms. The authors suggest that aggregation processes, due to both proximity to the isoelectric point of the solid and adsorbate bridging between particles, may have significant effects on surface-site availability.

• Research Organization: Univ. of Wisconsin, Madison
• DOE Contract Number: AC02-80EV10467
• OSTI ID: 5255421
• Journal Information: Environ. Sci. Technol.; (United States), Vol. 19:6
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
ADSORPTION
MATHEMATICAL MODELS
GOETHITE
CHEMICAL REACTION KINETICS
PHOSPHATES
SELENITES
SULFATES
AGGLOMERATION
ELECTROPHORESIS
PH VALUE
SOLUTES
THEORETICAL DATA
DATA
INFORMATION
KINETICS
MINERALS
NUMERICAL DATA
OXIDE MINERALS
OXYGEN COMPOUNDS
PHOSPHORUS COMPOUNDS
REACTION KINETICS
SELENIUM COMPOUNDS
SORPTION
SULFUR COMPOUNDS
520200* - Environment
Aquatic- Chemicals Monitoring & Transport- (-1989)