The synthesis of hierarchical porous Al 2 O 3 /acrylic resin composites as durable, efficient and recyclable absorbents for oil/water separation

In this work, we report a facile and inexpensive approach which was demonstrated for the creation of hierarchical porous Al2O3/acrylic resin composites as durable, efficient and recyclable absorbents for oil/water separation. Using hexadecyl trimethyl ammonium bromide (CTAB) as a structure-directing agent, the lamellar γ-AlOOH with porous architectures was successfully prepared via a hydrothermal route. The hierarchical Al2O3 clusters, as the inorganic phase of resin composites, retain the unique structure of lamellar γ-AlOOH by calcination treatment. In order to enhance the hydrophobic and oleophilic properties of Al2O3 clusters, silane coupling agent (A151) was used to modify the surface of Al2O3 clusters under microwave irradiation. The surface modified Al2O3 clusters exhibit excellent hydrophobicity, oleophilicity and chemical stability, owing to the tight binding of the hydrophobic functional groups on the inorganic Al2O3 clusters and the inherent stability of the grafted hydrophobic molecule chains. The porous Al2O3/acrylic resin composites were synthesized by suspension polymerization of butyl acrylate (BA) and methacrylic acid butyl ester (MBA) on the surface modified Al2O3 clusters under microwave irradiation in the presence of coupling agents. The porous Al2O3/acrylic resin composites can effectively separate oils and organic solvents with high oil absorption rate and high oil retention capacity. Moreover, the obtained resin composites have high oil uptake capacities due to the synergy absorption of porous Al2O3 clusters and acrylic resin. These excellent performances, such as excellent oil recoverability, excellent recyclability and high oil retention capacities, endow the material to be an ideal candidate to separate a variety of organic liquids from water.