Effect of Surface Sulfonation on the Ordered and Textural Properties of Vanadium and Iron Containing SBA-15

Sulfanation of SBA-15 by use of H 2 SO 4 as the synthesis acid and post surface sulfanation of hydrothermally synthesized V-, Fe-SBA-15 samples with different M/Si mole ratios were carried out by use of dilute sulfuric acid. The doubling of hydrogen ions’ amount in case H 2 SO 4 usage led to partial deterioration of the ordered structure. X-ray diffraction patterns showed that the metal loading to SBA-15 matrix caused increases in (100) plane reflections up to four-five times supporting the formation of longer hexagonal arrays. The improved ordered structure of metal-SBA-15 was not destroyed by post-sulfanation. Micro-mesoporus structure of the samples resembled type IV nitrogen isotherm with a H4 hysteresis loop of IUPAC classification. Increase of BET surface area accompanied with around 20% increase in micropore volume took place by metal contribution. Increases both in Saito–Foley (SF) mean micropore and Barrett–Joyner–Halenda (BJH) mean mesopore sizes were designated by the increase of M/Si ratio in the synthesis solution. Around 150-200 m 2 .g -1 decreases in BET surface area were accompanied by the decreases in the mesopore volume and mean mesopore dimensions, and partly increases in the micropore volume and mean micropore diameters were observed with sulfanation.