Investigation and optimization the study of Hexavalent Chromium elimination efficiency by activated carbon prepared from modified rice husk with sorbic acid

HaUI Institute of Technology, Hanoi University of Industry, 10000 Hanoi, Vietnam

^* Corresponding author: tahuong.hus@gmail.com

Abstract

The current work illustrates how successfully rice husk-activated carbon eliminates hexavalent chromium from aqueous solutions. The design of experiment (DOE) - response surface methodology (RSM) was utilized to build an appropriate experimental model. The experimental variables pH, contact length, and adsorbent dose were found, as well as their interactions and effects on Cr(VI) removal. The greatest result for Cr(VI) removal was obtained at pH = 2, agitation time of about 30.5 hours, and adsorbent dose = 4 g/l, with a starting hexavalent chromium content of 100 ppm. Hexavalent chromium removal is performed optimally under the parameters specified for these driving forces. ANOVA also demonstrated a strong coefficient of determination R2 > 99 %. Furthermore, Temkin isotherm and pseudosecond kinetic models with high R2 values were selected as useful for the inquiry. It illustrates that the removal of hexavalent chromium in studies is considered to follow a regular distribution of binding energies up to a given maximum binding energy. Furthermore, the rate of adsorption site occupancy is inversely proportional to the square of the number of unoccupied sites on the adsorbent.