Influence of divalent heavy metals on the aggregation of humic acids: Hofmeister effects

Chemosphere

Yekun Zhang

The adsorption of heavy metal at HA surface induce HA aggregation and sedimentation.  The ability to promote HA aggregation follows Zn2þ < Cd2þ < Cu2þ < Pb2þ.  Hofmeister effects mainly come from the non-electrostatic adsorption of ions on HA.  Classical coordination theory could not explain the non-electrostatic adsorption.