Protonation of phosphate on the surface of goethite as studied by CIR-FTIR and electrophoretic mobility

Journal Article · Thu Mar 01 04:00:00 EST 1990 · Langmuir; (United States)

DOI:https://doi.org/10.1021/la00093a015· OSTI ID:5479038

Tejedor-Tejedor, M I; Anderson, M A ^[1]

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1. Univ. of Wisconsin, Madison (USA)

CIR-FTIR in situ spectroscopic studies have provided evidence for the formation of three different type of complexes, protonated and nonprotonated bridging bidentate as well as a nonprotonated monodentate, between orthophosphate ions and surface Fe(III) of {alpha}-FeOOH particles in aqueous suspensions. The speciation of these complexes is a function of pH and phosphate surface coverage ({Lambda}). Furthermore, the combination of CIR-FTIR, adsorption isotherm, and electrophoretic mobility data allows them to calculate the intrinsic pK value (4.6) for the bridging bidentate iron phosphate surface complex.

• OSTI ID: 5479038
• Journal Information: Langmuir; (United States), Journal Name: Langmuir; (United States) Vol. 6:3; ISSN 0743-7463; ISSN LANGD
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ADSORPTION ISOTHERMS
AQUEOUS SOLUTIONS
CHEMICAL REACTIONS
DISPERSIONS
ELEMENTS
GOETHITE
INFRARED SPECTRA
IRON
ISOTHERMS
METALS
MINERALS
MIXTURES
OXIDE MINERALS
OXYGEN COMPOUNDS
PH VALUE
PHOSPHATES
PHOSPHORUS COMPOUNDS
SOLUTIONS
SPECTRA
SURFACES
TRANSITION ELEMENTS