Transformation of 2-Line Ferrihydrite to Goethite at Alkaline pH.

ABSTRACT: The transformation of 2-line ferrihydrite to goethite from supersaturated solutions at alkaline pH ≥ 13.0 was studied using a combination of benchtop and advanced synchrotron techniques such as X-ray diffraction, thermogravimetric analysis, and X-ray absorption spectroscopy. In comparison to the transformation rates at acidic to mildly alkaline environments, the half-life, t_1/2, of 2-line ferrihydrite reduces from several months at pH = 2.0, and approximately 15 days at pH = 10.0, to just under 5 h at pH = 14.0. The calculated-first order rate constants of transformation, k, increase exponentially with respect to the pH and follow the progression log₁₀ k = log₁₀ k₀ + a·pH³. Simultaneous monitoring of

SUBMITTER: Furcas FE 

PROVIDER: S-EPMC10603785 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature