First, the conversion of fructose into HMF has been investigated by use of KIT-5 a high hydrothermal stable mesoporous silica incorporated by Al atoms as a lewis acid catalyst and functionalized with sulfonic acid groups as bronsted acid catalyst and the comparison between two catalyst have been conducted for understanding the effectiveness of them in this reaction. The catalysts were characterized using XRD, BET, TGA, Pyridine-FTIR, Elemental mapping, SEM, and TEM techniques. The prepared catalysts were used to catalyze the conversion of fructose to 5- hydroxymethylfurfural (HMF) in DMSO. Various reaction parameters such as effect of reaction temperature, reaction time, catalyst loading, and solvent on HMF yield were investigated. The results showed 99.4% of HMF yield at 125?C after 45 min by using KIT-5-SO 3 H and 88.3% of HMF yield by using Al-KIT-5 as catalyst at 135?C after 60 min. The results show that the bronsted acid catalyst is more efficient than a lewis one in this reaction. In the next section, we used KIT-6 (a highly ordered mesoporous silica with cubic Ia3d symmetry) functionalized propyl-sulfonic acid groups as a heterogeneous solid acid nanocatalyst for the synthesis of tetrazole drivatives . The modified KIT-6 leads to more acidic character and better reactivity of it. Identification of catalysts was achieved by the techniques such as small angle XRD, IR, BET, TGA, SEM, elemental analysis and TEM. easy extraction and being compatible with the environment are the advantage of the method. The catalyst recycled 4 times and the recycled catalyst showed good yields.