Removal of metal ions Cd(II), Cr(VI) and Ni(II) from aqueous solution using an organic aerogel and carbon aerogel obtained by acid catalysis

In this work, we evaluated the adsorption capacity of the metal ions Cd(II), Cr(VI) and Ni(II) from aqueous solution of an organic aerogel, a carbon aerogel and a commercial activated carbon. Aerogel (Ae) was obtained by acid catalysis using HCl, achieving a quick synthesis, then, a process of carbonization to obtain the carbon aerogel (CAe) was performed. Structural, textural and chemical parameters of the porous solids obtained were characterized by different experimental techniques: scanning electron microscopy (SEM), adsorption isotherms of N2 at 77 K and CO2 at 273 K, Boehm titrations and pHPZC determination. The three adsorbents were employed in simple adsorption systems of Ni(II), Cd(II) and Cr(VI) from aqueous solution. It was determined that the synthesized aerogel is the material that performed the highest adsorption capacity of the three metal ions: Ni (32.2 mg g-1) Cd (18.6 mg g-1) and Cr (35.5 mg g-1).