Preparation of mesoporous γ-Al2O3 with high surface area from an AlOOH extract of recycling biomass ash

This study explores the potential application of recycled materials extracted from arboreal ABA (ABA); this waste is used as an alternative source of aluminium oxyhydroxide for the synthesis of γ-Al2O3 with high surface area-based mesoporous materials with interesting applications in environmental remediation. The aluminium present in ABA was extracted by desilication and reflux in acid and subsequently converted to mesoporous γ-Al2O3 via a sol–gel process with Pluronic P-123 as surfactant. The surface of that material was successfully functionalized with racemic glycine (GLY) and N,N-dimethylacetamide (DMAC) by liquid impregnation in order to study and compare their applications in capture of Fe3+ cations. All the materials were unambiguously characterized by adsorption-desorption isotherms of N2 at 77 K, X-ray fluorescence (XRF), elemental analysis (EA), X-ray diffraction (XRD), diffuse reflectance infrared fourier transform spectroscopy (DRIFTS), scanning electron microscopy with dispersive energy detector of X-ray (SEM-EDS), transmission electronic microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). This process afforded γ-Al2O3 with high purity and the surface area of the mesoporous materials ranged from 115 m2 g−1 for AlOOH to 230 m2 g−1 for γ-Al2O3. The achieved surface functionalization was of 2 and 3 wt% with glycine and DMAC, respectively. The effective performance of these materials (both pristine and functionalized) in the removal of Fe3+ ions from an aqueous solution was evaluated in batch systems. In particular, the materials presented extraction capacities of about 78.2% for bare γ-Al2O3, 83.2% for Al-GLY and 93.9% for Al-DMAC.The authors acknowledge the financial support of this project by USA1799 Vridei 091912JP_GO Universidad de Santiago de Chile, Dicyt Grant No 0921640PK and 092112PK, ANID-CONICYT Grant No ACT1410, ANID-FONDEF Grant ID18I10229, Generalitat Valenciana (PROMETEOII/2018/076). Acknowledgements also go also to USAI, Faculty of Chemistry, UNAM, and to PAIP Project No 5000 9038, Faculty of Chemistry, UNAM. Mauricio Gómez acknowledges CONICYT (National Commission for Scientific Research and Technology Commission) for financial support Grant No 21150413, to the Mexican Agency of International Cooperation for Development AMEXCID, Alianza del Pacifico Scholarship