No abstract

No abstract

in Wiley Online Library (wileyonlinelibrary.com).Sulfonic acid functionalized SBA-15 (SBA-Pr-SO 3 H) as a new nanoporous solid acid catalyst was applied in the green one-pot synthesis of spirooxindole-4H-pyrans via condensation of isatins, malononitrile or methyl cyanoacetate or ethyl cyanoacetate, and 4-hydroxycoumarin in water solvent. SBA-Pr-SO 3 H was proved to be an efficient heterogeneous nanoporous solid acid catalyst with a pore size of 6 nm that could be easily handled and removed from the reaction mixture by simple filtration and can be recovered and reused for several times without any loss of activity. The significant merits of present methodology are its simplicity, short reaction time, good yields, and environmentally benign mild reaction condition as water was used as a green solvent.

The e ect of two di erent crystal species of alumina on the hydrodesulfurization activity of the corresponding CoMo catalysts was studied. Cylindrical extruded alumina with two di erent crystal structures, i.e., -Al2O3 and -Al2O3, was prepared using boehmite and nitric acid as a peptizing agent by calcination at 550 C and 900 C, respectively. Al2O3 supports were impregnated with 9 wt.% of Mo and 2 wt.% Co by an incipient wetness impregnation method. CoMo/Al 2 O 3 catalysts were used for hydrodesulfurization (HDS) and hydrodenitri cation (HDN) of Iranian Straight-Run Gas Oil (ISRGO). The supports and catalysts were characterized by nitrogen adsorptiondesorption isotherm, XRD, UV-vis-DRS, TPD, TPR, CO chemisorption, and ICP-OES. The HDS activity of CoMo/ -Al2O3 catalyst was higher than that of CoMo/ -Al2O3 and was found to be 95.74%. This result was obtained from the formation of larger CoMoO 4 and MoO 3 crystals in CoMo/ -Al 2 O 3 catalyst, thus reducing the active metal phase dispersion and the performance of the catalyst. The HDS activity of CoMo/ -Al2O3 catalyst was remarkable as the metal content of the catalyst was low. The HDN activity of CoMo/ -Al2O3 was also about 66%.

No abstract