Surface modification of Cameroonian magnetite rich clay with Eriochrome Black T. Application for adsorption of nickel in aqueous solution

► The surface of a Cameroonian magnetite rich clay was modified using Eriochrome Black T, EBT. ► The immobilized surfaces were used for nickel (II) ion adsorption from aqueous solution. ► The characterization of the surface modification was also performed with IR and ZPC measurements. ► The EBT-functionalized magnetite rich clay presented a binding capacity of nickel (II) ion about 30% higher compared to the untreated sample.