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

In this study, the surface of Cameroonian magnetite rich clay was modified using Eriochrome Black T, EBT by the batch adsorption method. The EBT-modified magnetite rich clays were used for nickel ions adsorption from aqueous solution. The effect of various experimental factors; the pH of solution, the influence of concentration, the temperature, the contact time and the particle size of the sample were studied by using the batch technique. Adsorption process was better described by the pseudo-second-order kinetic and Tempkin isotherm model. The results showed that the EBT adsorption onto samples is affected by the pH of solution and the maximum EBT ion adsorption takes place between pH 2 and pH 3. The characterization of the surface modification was performed with FTIR and ZPC measurements. The FTIR shows that chemisorption took place at the surface of the bulk samples. The EBT-modified magnetite rich clay presented a binding capacity of nickel ions about 30% higher compared to the unmodified samples from an initial nickel ions concentration of 5.26 mmol using 0.5 g of sample.