Ethylenediamine attached to silica as an efficient, reusable nanocatalyst for the addition of nitromethane to cyclopentenone

Hexagonal mesoporous silica modified with copper phthalocyanine as a photocatalyst for pesticide 2,4-dichlorophenoxiacetic acid degradation

“…4 presents the nitrogen adsorption isotherms of the SiCuF 16 Pc and HMS materials. The isotherms reveal that the adsorptiondesorption process is not reversible and, in addition, is caused by the moment where the capillary tension in the pores exceeds the intermolecular forces between nitrogen molecules [27][28][29]. The isotherm is reversible up to a relative pressure of about 0.65.…”

“…The isotherm is reversible up to a relative pressure of about 0.65. Irreversibility is observed between 0.65 and 0.95, whereas the pores of the material abruptly lose their adsorbate, which is a characteristic of the condensation in primary mesopores [27][28][29]. From the nitrogen adsorption isotherms it was calculated the BET surface area of the materials, which gave 820 and 198 m 2 g −1 for HMS and SiCuF 16 Pc, respectively.…”

Photocatalytic decouloration of malachite green dye by application of TiO2 nanotubes

“…This irreversibility is a consequence of capillary condensation in mesopores. Indeed, this isotherm shows that the TiO 2 nanotubes are predominantly formed by micropores with mesoporous sites forming an agglomerate structure [36][37][38]. The surface area values of catalysts were calculated by the application of BET equation in N 2 isotherms, which gave 8.0 and 76.0 m 2 g −1 for TiO 2 anatase and TiO 2 nanotubes, respectively.…”

Modificação química de sílica gel obtida de areia e seu uso na remoção de Cu2+, Zn2+, Mn2+

“…Para evitar a poluição de rios e mares é essencial tratar os efluentes antes de serem descartados nesses meios. Nesse quesito, ganha importância a sílica como um sólido poroso com propriedades químicas e físicas específicas que garantem uma diversidade de aplicações tecnológicas 14,15 .…”