Adsorption removal of copper(II) from water by zero valent iron loaded dendritic mesoporous silica

The object of research is synthesized dendritic mesoporous nanoscale silica (DMSN) modified with zero-valent iron (Fe0@DMSN). This material exhibits a high adsorption capacity for heavy metal ions, in particular copper, whose increased content in the aquatic environment poses a threat to living organisms. In this regard, the main physicochemical features of the removal of copper cations from the aqueous medium using the obtained sample were investigated. The morphology of the obtained dendritic silicas was studied by electron microscopy and the presence of a layer of zero-valent iron was confirmed by X-ray diffraction analysis and infrared spectroscopy. The parameters of the porous structure of the synthesized materials were determined. It was found that after modification of mesoporous silica with particles of zero-valent iron, the value of its specific surface area decreased from 504 m2/g to 312 m2/g. This may be due to the formation of a Fe0 layer not only on their surface but also in the channels of the inorganic matrix, which has a unique dendritic structure characteristic of this type of particles. At the same time, the number of active centers increases due to the enrichment of the silica surface with functional modifier groups that show a high affinity for metal cations. The adsorption capacity of Fe0@DMSN towards Cu2+ ions has been studied and it has been shown that the maximum adsorption value is 39.8 mg/g, which is significantly higher than that of the initial synthesized DMSN sample (0.7 mg/g). The experimental data obtained indicate that the obtained sorption material based on dendritic mesoporous silica nanoparticles with a layer of reactive zero-valent iron can be used for the purification of water contaminated with metal ions. In addition, the magnetic properties of such materials, known and proven by various scientists, will make it easy to separate the solid phase in the processes of sorption water purification using magnetic separation.