Natural organic matter inhibits Ni stabilization during Fe(II)-catalyzed ferrihydrite transformation

Trace metals, such as nickel (Ni), are often found associated with ferrihydrite (Fh) in soil and sediment have been shown to redistribute during Fe(II)-catalyzed transformation of Fh. Fh, however, is inhibited when natural organic matter (NOM) To explore whether NOM affects the behavior Ni we tracked distribution, Fe atom exchange, mineral Fh coprecipitated Suwannee River (SRNOM-Fh). As expected, absence Fe(II), SRNOM-Fh did not transform secondary minerals after two weeks. We further observed little difference adsorption on compared In presence that was more susceptible acid extraction than Specifically, almost double amount remaining mild SRNOM-Fh. XRD showed transformed goethite magnetite whereas despite 57Fe isotope tracer experiments confirmed underwent extensive exchange aqueous Fe(II). Our findings suggest may be sufficient for obvious stabilization necessary occur.