Aluminum-induced colloidal destabilization of iron-organic matter nanoaggregates

The structural organization of heterogeneous and multiphase natural aggregates depends on the biophysicochemical conditions prevailing in environment, with major ions playing a crucial role. In this study, impact aluminum (Al) iron-organic matter (Fe-OM) was investigated since Al can interact OM be incorporated Fe-oxyhydroxides or adsorbed their surface. Mimetic environmental Fe-OM-Al were synthesized at various [Fe] [Al] constant [OM]. At low [Al + Fe], exhibit colloidal behavior. Within aggregates, Fe is present as Fe(III)-oligomers ferrihydrite-like nanoparticles whereas forms monomers, oligomers small polymers, all bound to OM. phases interacted each other. high [Fe Al], monomers/oligomers polymerized which increases size quantity polymers then branched out OM, resulting large settling network. effect Fe-OM structure could also have an fate pollutants. occurrence amorphous hydroxides increase lead higher availability surface reactive sites subsequently sorption capacity for pollutants that greater affinity minerals than organics.