Surface modification of alumina with P 2 O 5 and its application in 2-octanol dehydration

S Nazer, HA Dabbagh, AN Chermahini, H Farrokhpour, Reaction Kinetics, Mechanisms and Catalysis, 1-18, 2020

Alumina and phosphorus-alumina with different morphologies were synthesized by the sol–gel method. The morphology, structure, size, phase composition, acidic properties, and thermal behavior were examined by FESEM, TEM, XRD, FT-IR, BET, EDS, NH₃-TPD, and TGA-DTA, respectively. It can be found that the morphology of alumina can change from worm-like to spherical by using acetonitrile/2-octanol solvent mixture and by modifying the synthesis steps. Also, the semi-crystalline structure of γ-alumina was changed to amorphous with improved surface area (from 150 to 229 m² g⁻¹). The addition of phosphorus pentoxide to amorphous alumina with the ratios of 1:9, 2:8 and 1:1 reduced the surface area of the catalyst after calcination from 229 to 129, 16 and 39 m²  g⁻¹, respectively. With the increase of phosphorus/aluminum ratio and an increase in calcination temperature, the structure of phosphorus …