Monodispersed Silica Nanoparticles Incorporated Nanocomposites of Gelatin and Psyllium for Sequestration of Noxious Pollutants

Abstract

In the present study, monodispersed silica nanoparticles (SNPs) were synthesized by sol–gel method. To enhance the properties like surface roughness, surface area, and percentage swelling, the SNPs were incorporated into the hydrogel Gelatin and Psyllium to synthesize a nanocomposite material. The percentage of swelling was optimized by varying different reactions parameters like temperature, pH, backbone ratio, monomer concentration, cross-linker concentration, initiator concentration and amount of solvent. On incorporation of SNPs, the great enhancement in various properties likes surface roughness, and percentage swelling (1656% from 1100%) was observed. As an adsorbent, the synthesized nanocomposite was investigated with a tremendous hike in the dye removal efficiency on the incorporation of SNPs into the hydrogel network. The synthesized nanocomposite was found to remove 2.385 mg g−1 of Brilliant green (BG) in 5 h whereas 1.56 mg g−1 removal of Xylenol orange (XO) within 4 h. The higher values of K2 and closeness of theoretical and experimental adsorption capacity values at all the concentrations in both the dyes confirmed the adsorption kinetics data fitted well with pseudo-second order rate model. The correlation values (0.966 for BG and 0.995 for XO) and favourable RL (0.345 for BG and 0.263 for XO) of the adsorption data suggested better fit for Langmuir adsorption for both the dyes. Further, the negative values of ΔGo and ΔHo confirmed the adsorption of BG and XO dyes on the adsorbent is a feasible reaction. The reusability affinity of the synthesized SNP based nanocomposite up to 4 cycles outshine as a superior adsorbent material for the removal of cationic and anionic dyes from waste water.