Also, the process is in better agreement with pseudo-second-order kinetic model, indicating a chemisorption controlled process. The experiment data fitted well to Langmuir model indicating anion species monolayer adsorption on the cRH homogeneous surface. The optimized condition was verified and 91.13% removal efficiency was achieved. Taguchi experimental design predicted initial Cr (VI) concentration of 25 mg/L, contact time of 90 min, 2 g cRH dosage and pH of 2 as the optimum conditions to achieve 91.48% removal efficiency. These findings indicate that Cr(VI) in seawater was reduced either before or after carbonate precipitation, which might have caused Cr isotopic fractionation. Also the SEM micrograph showed the pores of different sizes which favoured the adsorption of Cr(VI). The results showed the bulk density (0.392 g/cm 3) and surface area (192 m 2/g) which revealed the presence of numerous sorption sites on the cRH. The adsorption process was optimized by considering four independent process parameter at three variation levels using Taguchi design approach. Also, point-of-zero pH (pHzero), specific surface area (m 2/g) and bulk density (g/cm 3) of the cRH were determined. The cationic modified risk husk (cRH) was characterized by scanning electron microscopy (SEM) and fourier transform infrared (FTIR) spectroscopy. The rice husk was prepared and modified cationicaly. The current work study the adsorption capacity of modified rice husk for the removal of Cr(VI) from aqueous solution.
0 kommentar(er)
