Abstract
The facile synthesis of the advanced cobalt-based materials [1.0Co/Al2O3 (A), 0.5Co/Al2O3 (B), 3.5CoNaY (C) and 0.4CoHY (D)] is reported. The characterization of the materials was carried out by X-ray photoelectronic, energy-dispersive X-ray, atomic absorption and low-temperature nitrogen adsorption methods. These materials were used for a comparative degradative and adsorptive removal of carmoisine azo dye in water. The adsorptive and degradative removals were 62.0-96.1% and 68.1-96.1% for all four materials. The degradation was occurred by hydroxyl radicals and peroxy free radicals. The adsorptive removal followed Langmuir, Temin and Dubinin-Radushkevich models. The adsorption obeyed pseudo-first-order kinetics and liquid film diffusion mechanism. The results indicated that both degradative and adsorptive phenomena had comparative removal capacities. The removal capacities of all four materials were C > A > D > B. The maximum removal was obtained by material C (96.1%) and A (90.0%) in a wide pH range of 3.0-9.0. The reported methods are very effective, efficient and inexpensive for the removal of carmoisine azo dye in water. These methods may be used to remove the reported dye at a large scale in any water resource.