Investigating the effects of different chemical conditions in aqueous solutions on the adsorption of Eu(III) onto illite colloids

Under diverse hydrochemical circumstances, the adsorption characteristics of Eu(III) onto illite colloids were investigated. Batch experiments were carried out to assess the impact of various parameters, including reaction duration, temperature, the initial Eu(III) concentration, pH value, ionic strength, and the presence of macromolecular organic matter, on the adsorption efficacy of Eu(III) by illite colloids. The findings reveal that the adsorption of Eu(III) onto illite colloids is a swift and effective process, significantly influenced by pH. The ionic strength of the solution and the presence of different cations can impede the adsorption rate of Eu(III) on illite colloids. Conversely, the presence of fulvic acid can notably enhance the adsorption rate of Eu(III) in acidic environments. Analysis of the isothermal adsorption model data suggests that the adsorption process is a spontaneous and endothermic reaction, predominantly featuring single-layer adsorption.