Adsorption of perchlorate by cationic modified adsorbent in a fixed bed continuous flow column

Abstract

BACKGROUND: In the present investigation, rice husk modified by Cetyltrimethylammonium bromide (CTAB) was used for the adsorptive removal of perchlorate by fixed column experiments from aqueous solution. The performance of the cationic modified rice husk (MRH) was characterized by Fourier transform infrared analysis. Experiments were carried out in a properly designed test rig consisting of a fixed-bed column of the cationic MRH with provision for admitting variable flow rates of the adsorbate at specified concentrations. The experimental unit can vary the column heights of the adsorbent. RESULTS:The influence of parameters such as inlet perchlorate feed concentration, flow rate of feed and height of bed used was analyzed based on the breakthrough curves and saturation time of the cationic modified adsorbent. The ranges of parameters were determined from parameter optimization studies using several sets of batch experiments conducted during the course of the preliminary investigation in the study. The breakthrough curves obtained from the column studies on the adsorption of perchlorate on MRH at various conditions were analyzed using four different kinetic models and the experimental and model-predicted breakthrough curves were used to obtain the parameters of the adsorption process in the column. CONCLUSIONS: Adams-Bohart and ded depth service time (BDST) models fitted better in the initial period of the adsorption process. Different nonlinear statistical methods were used to evaluate the best model for the column performance in the adsorption of perchlorate in a cationic modified adsorbent.

Cetyl Trimethyl Ammonium Bromide (CTAB) functionalized sodium silicate for Naphtol Green B and Congo Red adsorption.

“…Some works showed that calcining rice husks at 500°C for 1 hour increased the adsorption of basic dyes. Rice husks modi ed with CTAB (Cethyltrimethylammonium bromide ) have been used to remove Congo Red, Methyl Orange, and perchlorate ions [18,22,23]. Raw rice husks and CTAB-modi ed rice husks have also been used for the adsorption of ammonium and nitrate ions [24].…”