Particle size, charge and colloidal stability of humic acids coprecipitated with Ferrihydrite.

Highlights: [•] Colloidal properties of Ferrihydrite humic acid coprecipitated are investigated. [•] Fe–HA coprecipitate increase in the size and negative charge compare with HA. [•] ξ-Potential measurements revealed a increment of negative charge for Fe–HA at pH 4–8. [•] At neutral alkaline pH the Fe–HA negative charge enhancing colloidal stability. [•] Ferrihydrite–HA coprecipitate could play an important role in the carbon stabilization. [ABSTRACT FROM AUTHOR]