The present invention relates to the process of obtaining adsorbent materials based upon supported metal species on porous silicates, and their use for reducing the amount of sulfur and nitrogen contaminants in petroleum fractions and products derived of, i.e., light and heavy gas oils, FCC gasoline and fuels, where FCC stands for Fluid Catalytic Cracking process.Therefore, the invention comprises the selection, preparation, modification and adsorptive properties of the abovementioned porous materials, which are based on porous silicates with metal species intercalated and/or impregnated, such as Ti(O,OH), Mg(O,OH)—, Zr(O,OH)—, Fe(O,OH), Al(O,OH). Also, additional options were considered, for example those comprising metals from the 1st and 2nd transition series, such as Cu+, Ni2+, Zn2+, Fe2+, Ag+, Co2+, Ti4+, V2+,5+, Cr3+ and Mn2+.