Adsorption of sulfur and nitrogen compounds on hydrophobic bentonite

The successful synthesis of hydrophobic magnetic composites formed by carbon filaments on bentonite surface has been obtained via chemical vapor deposition of ethanol and studied by electron microscopy, XRD, Mössbauer spectroscopy, Raman, and thermal analysis measurements. Bentonite clay was impregnated with different concentrations of iron salt and subjected to a chemical vapor deposition using ethanol as carbon source. The results suggest the reaction of iron on the surface of bentonite with ethanol leading to the formation of reduced iron phases and carbon. The carbon deposited is present as graphite, amorphous and filaments and the resulting materials show hydrophobic behavior besides magnetic properties conferred by the iron phases. This magnetic property is very interesting and allows the materials to be easily removed from the system. The hydrophobic bentonite was used as adsorbent of sulfur and nitrogen compounds, important contaminants in fuels, showing adsorption capacity of 38.7 mg g− 1 and 54.5 mg g− 1 for nitrogen and sulfur compounds respectively, a very high adsorption capacity compared with other materials with carbon presented in the literature.