Magnetic aerogels based on reduced graphite oxide – sorbents of the carcinogenic compound K₂Cr₂O₇

Nanocomposites based on graphite oxide airgel and superparamagnetic iron oxide nanoparticles (rGO ⋅ Fe₃O₄) are able to sorb potassium dichromate from aqueous solutions. The superparamagnetic nature of the composite makes it possible to extract it after the completion of the sorption process from the pollutant solution using an external magnetic field. The dependence of the degree of sorption of potassium dichromate by aerogels of the composition rGO ⋅ Fe₃O₄ on the mass of the sorbent, acidity, and temperature of the medium was studied. It has been shown that in order to increase the degree of potassium dichromate sorption by the rGO ⋅ Fe₃O₄ magnetic airgel, the process is best carried out at room temperature in media with low pH values. The results obtained make it possible to propose airgels based on graphite oxide and rGO ⋅ Fe₃O₄ iron oxide nanoparticles as environmentally friendly sorbents for water purification from the carcinogenic substance potassium dichromate. The proposed materials after the end of the sorption process can be completely removed from the reaction medium using an external magnetic field, thereby preventing their action as pollutants. It is important to note that the described 3D structures based on graphite oxide and nanoparticles of superparamagnetic iron oxide Fe₃O₄ are of practical importance for the treatment of wastewater from enterprises using an oxidative method for removing phenols, cresols, and cyan-containing substances from impurities using potassium dichromate and sulfuric acid.