Removal of Cr(VI) from aqueous solution using brick kiln chimney waste as adsorbent

Abstract

A B S T R A C THeavy metals are toxic to aquatic flora and fauna even in relatively low concentrations. Chromium is a commonly occurring toxic metal in ecosystems. This study aims the adsorption of Cr(VI) on a novel low-cost carbonaceous material under different experimental conditions such as contact time, initial concentration of metal ions, pH, and temperature. The adsorbent was characterized by using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The equilibrium data were fitted well with Langmuir and Freundlich isotherms. Adsorption kinetics of Cr(VI) ions onto chimney waste adsorbent were analyzed by pseudo-first-order and pseudo-second-order models. The adsorption process is favored by acidic pH and followed the second-order kinetics. Various thermodynamic parameters like activation energy (E a ), Gibbs free energy change (DG o ), enthalpy change (DH o ), and entropy change (DS o ) were calculated. The results showed that the carbonaceous material obtains from bricks kiln chimneys can be efficiently used for Cr(VI) removal from wastewater.

Application of chitosan-citric acid nanoparticles for removal of chromium (VI)

“…At the equilibrium situation, the maximum removal efficiency of 83.54 and 61.75% for CS and CS-CA nanoparticles, respectively, was attained. This finding is in accordance with previous research [16]. In general, the time required to reach equilibrium was less in this research as compared to previous studies.…”

Desulfurization of Model Oil through Adsorption over Activated Charcoal and Bentonite Clay Composites

“…Consecutive peaks appearing around 1110 and 1050 cm −1 correspond to bending vibration of the Si–O bonds of pure bentonite . The octahedral sheet characteristics were attributed to the band between 570 and 400 cm −1 .…”

“…The amount of DBT removed by the adsorbent was reported in percentage of adsorbed concentration of DBT in mg to the initial concentration of DBT per gram of adsorbent according to Eqs. (1) and (2) [37]:…”

“…2. The spectrum of the AC 50 composite involves major absorption peaks positioned at 3610 and 3410 cm -1 which corresponds to O-H stretching vibrations of hydroxyl groups on the surface of AC or aluminosilicate frameworks of pure bentonite clay [37]. The peak centered at 2490 and 1680 cm -1 may be assigned to O-H deformation in absorbed water and C=C in AC, respectively [45,46].…”

Use of HCl-modified bentonite clay for the adsorption of Acid Blue 129 from aqueous solutions

“…In recent decades, various methods have been developed for the removal of dyes from wastewaters, such as chemical oxidation, biodegradation, membrane separation, electrochemical processes, coagulation/ flocculation [21][22][23][24][25][26][27], and adsorption [28][29][30][31][32][33][34][35][36][37][38]. Adsorption is considered an effective way to remove dyes from wastewater, since it is a non-destructive, simple, and economical method of treatment [39][40][41][42][43][44][45].…”