Enhanced Removal of Cr(III), Mn(II), Cd(II), Pb(II) and Cu(II) from Aqueous Solution by N-functionalized Ordered Silica

Chelating and ion-exchange N-functionalized mesoporous silicas (SBA-15) as selective adsorbents for removal of heavy metals were synthesized using template method. Fourier transform infrared spectroscopy, TEM analysis, N2 adsorption/desorption isotherms titration analysis confirmed successful functionalisation the tri-sodium salt N-(triethoxysilylpropyl)ethylenediaminetriacetic acid (EDTA), protonated primary amine (NH3+Cl−) its combinations onto silica (SBA-EDTA/NH2). The obtained materials featured beneficial properties SBA-15 with high surface area successfully fictionalized N-containing groups. series investigated Cr(III), Mn(III), Pb(II), Cd(II) Cu(II) from model water solutions. adsorption target ions increased increase pH concentration in solution. equilibrium data well fitted to Langmuir isotherm maximum monolayer capacities cations Cd(II), Cr(III) Mn(II) 185.6 mg g−1, 111.2 57.7 g−1 49.4 respectively. chelating interaction was considered main mechanism metal (Cr(III), Mn(II), Cu(II)). SBA-EDTA SBA-EDTA/NH2 samples toward studied consistent Lewis ‘hard soft acids bases’ theory. efficiency near 96–92% during three regeneration cycles. All these results indicated that produced promising applications environmental analytical separation fields.