Photocatalytically modified ceramic adsorbents were synthesized for the removal of high concentration Cu (II) and Co (II) ions from their aqueous solutions. The raw material, diatomaceous aluminosilicate mineral was modified using silver and anatase titanium oxide nanoparticles. Batch adsorption experiment was carried out on the targeted metal ions and the results were analyzed by the Langmuir and Freundlich equation at different concentrations (100–1000 mg/l) and the characteristic parameters for each adsorption isotherm were determined. As-received raw materials do not exhibit any sorption capacity for high concentration Cu²⁺ and Co²⁺ adsorbates. However, the adsorption isotherms for modified diatomaceous ceramic adsorbents could be fitted well by the Langmuir model for both Cu²⁺ and Co²⁺ with correlation coefficient (R) of up to 0.99953. The highest and lowest monolayer coverage (q _max) were 121.803 and 31.289 mg/g for Cu²⁺ and Co²⁺, respectively. The separation factor (R _L) in the experiment was less than one (<1), indicating that the adsorption of metal ions on the Ag–TiO₂-modified ceramic adsorbent is favorable. The highest adsorption capacity (K _f) and intensity (n) constants obtained from Freundlich model are 38.832 (Cu²⁺ on ZEO-T) and 5.801 (Co²⁺ on STOX-Z).

Photocatalytic ceramic adsorbents were prepared from locally sourced kaolinite clay minerals for the removal of copper and cobalt ions from high concentration aqueous solutions. The minerals were treated with mild acid before modification using silver nanoparticles sources and titanium-oxide nanoparticles. Batch adsorption experiment was carried out on the targeted ions and the results were analyzed by Langmuir and Freundlich equation at different concentrations (100–1000 mg/l). As-received raw materials do not exhibit any adsorption capacity. However, the adsorption isotherms for modified kaolinite clay ceramic adsorbents could be fitted well by the Langmuir model for Cu²⁺ and Co²⁺ with correlation coefficient (R) of up to 0.99705. The highest and lowest monolayer coverage (q_max) were 93.023 and 30.497 mg/g for Cu²⁺ and Co²⁺, respectively. The separation factor (R_L) was less than one (<1), indicating that the adsorption of metal ions on modified ceramic adsorbent is favorable. The highest adsorbent adsorption capacity (K_f) and intensity (n) constants obtained from Freundlich model are 14.401 (Cu²⁺ on KLN-T) and 6.057 (Co²⁺ on KLN-T).