| Abstrakt: |
Al2O3-ZrO2 composite membranes were synthesized through the sol-gel polymeric route of ZrCl4 and AlCl3 in the presence of acrylic-acrylamide copolymer as a template. The dried samples were characterized by DSC, TGA, FTIR, XRD and TEM to determine the thermal behaviour, chemical composition, crystal structure, shape and size of the particles. Octyltrichlorosilane was chosen as a silane coupling agent to increase the hydrophobic nature of the prepared membranes. The morphological structure, hydrophobic nature, water permeability and desalination efficiency of the prepared membranes were studied using SEM, contact angle measurements, permeability and an NaCl rejection coefficient (R%). The crystal structure of zirconia and alumina particles in the composite was affected by the AlCl3 and ZrCl4 feed ratio. As the zirconia concentration increased, the average particle size of the composite particles became larger, and the uniformity of the membrane layer decreased. The composite AZ25 [alumina (75 mass-%)-zirconia (25 mass-%)] showed a uniform crack-free membrane layer with a pore diameter of 41 nm, a porosity of 27.34%, with a great hydrophobic nature with the contact angle reached at 116℃.This membrane could withstand calcination temperatures up to 700℃, as the alumina and zirconia were present in their active forms; gamma-alumina and tetragonal, respectively. The membrane produced from this composite showed a high surface area of 204.9 m²/g with a respective particle size of 6.95 nm. Moreover it showed a moderate ability to reject NaCl from water with a rejection coefficient of 57.42%, with a high permeation flux of 17.5 L·h-1m-2 at 75℃. [ABSTRACT FROM AUTHOR] |
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