Removal of hexavalent chromium from aqueous solutions using Ni–SiO$$_{2}$$ nanomaterials

Abstract

This study describes an effective method developed for the removal of hexavalent chromium, Cr(VI), from an aqueous environment. In this study, the Ni-SiO 2 nanomaterial was synthesized by the sol-gel method and then characterized by field emission scanning electron microscopy, X-ray diffraction and energy dispersive X-ray spectroscopy. The prepared nanomaterial was then employed as an adsorbent with significant properties of high surface area and uptake capacity. Adsorption conditions of Cr(VI) onto the Ni-SiO 2 nanomaterial were optimized by altering different parameters (pH, initial Cr(VI) concentration and different periods of time). An amount of 100.75 mg g −1 was estimated as the maximum uptake capacity of the Ni-SiO 2 nanomaterial at pH 4.0. The experimental data of Cr(VI) adsorption onto the Ni-SiO 2 nanomaterial were fitted well to the Langmuir isotherm and pseudo second-order kinetic models. Moreover, the adsorption of Cr(VI) onto the Ni-SiO 2 nanomaterial was not influenced even in the presence of different coexisting ions. Finally, the recommended methodology was applied on several environmental water samples.

Development of nanohybrid dental composite containing mesoporous carrier silica particles: Synthesis particles, determination of fluoride adsorption capacities, and addition of the composite

“…Adsorption isotherms in mesoporous solids conform to the Type V model. [37,38] F I G U R E 5 Flexural strength graph of composites prepared by increasing the total amount of particles and decreasing the organic matrix or PMMA ratios. PMMA, polymethyl methacrylate The adsorption-desorption t-plot results of these particles are shown in Table 3.…”

“…Adsorption isotherms in mesoporous solids conform to the Type V model. [ 37,38 ] The adsorption–desorption t‐plot results of these particles are shown in Table 3.…”