Removal of chromium (VI) from aqueous solution using chemically modified corncorb‐activated carbon: Equilibrium and kinetic studies

Abstract

Removal of Cr(VI) ions from aqueous solution was investigated using activated carbon obtained from acid modified (AMCAC) and unmodified corncorb (UMCAC) by batch adsorption technique at 30°C. H2SO4 acid of 10N, 20N, and 30N concentrations were used for the modification of activated carbon. The effect of different adsorption parameters, such as pH, initial Cr(VI) ion concentration, contact time, and adsorbent dosage were studied. The 10N acid modified activated carbon (AMCAC) was effective for the maximum removal of Cr(VI) at pH 6.0, and equilibrium was attained in 60 min. Kinetic studies show that the pseudo‐second‐order kinetic equation was best suited for removal of Cr(IV) ions from aqueous solution. Adsorption equilibrium data were fitted to Langmuir, Freundlich, and Redlich‐Peterson adsorption isotherms. The maximum adsorption capacities of UMCAC and AMCAC with respect to Cr(VI) ions were calculated from Langmuir isotherm, and found to be 22.82, and 54.11 mg/g respectively. FTIR spectra of the adsorbent before and after adsorption with Cr(VI) indicated that hydroxyl, halide, and aldehyde groups are present in the major binding sites which play an important role in the removal of Cr(VI) ions. © 2012 American Institute of Chemical Engineers Environ Prog, 32: 673–680, 2013

Preparation and characterization of higher degree‐deacetylated chitosan‐coated magnetic adsorbent for the removal of chromium(VI) from its aqueous mixture

“…The alkalinity of solution was obtained by the reagents such as 0.1 M of HCl, and 0.1 M of NaOH that enhanced the process economics as well as the effective reusability performance of the magnetic Chitosan . In the end of every adsorption–desorption cycle, the final Cr(VI) concentrations ( C f ) were analyzed by the atomic adsorption spectroscopy . The adsorption–desorption percentage efficiencies of magnetic chitosan can be calculated from eq.…”

“…In the present research study, it has been described the outcome of batch experiment on reduction of Cr(VI) from its aqueous mixture using magnetic chitosan . The operating conditions of the batch experiments such as initial Cr(VI) concentration, pH, contact time, dosage of adsorbent were examined with response surface methodology (RSM) by Box‐Behnken experimental design (BBD) . Table summarizes the BBD for the reduction of Cr(VI) using various adsorbents…”

Assessment of cationic dye biosorption onto anaerobic digested sludge: Spectroscopic characterization

“…Here, 100 mg of solid sample was mixed with 1 mL of DMSOd 6 . The sample was agitated and incubated for 24 h at 258C.…”

Equilibrium and kinetic studies on the adsorption of Ni(II) ion from an aqueous solution using activated carbon prepared fromTheobroma cacao(cocoa) shell

“…Of late, the adsorption technique has evolved as an economically feasible method for the removal of heavy metal pollutants. Low cost adsorbents are generally preferred in adsorption techniques, especially low-cost activated carbon prepared from naturally obtained bio waste, such as pomegranate peel [12], rice husk [13], coir pith [14], corn cob [15], cashew nut shell [16], coconut shell [17], pistachio nut shell [18], Guazuma ulmifolia seeds [19], palm shell [20], etc.…”