Chromium (VI) Adsorption on Modified Activated Carbons

Abstract

The paper presents the research of adsorptive properties of activated carbons to chromium (VI) removal from the water solution. Different types of carbon were investigated: WD-ekstra (WDA), WD-ekstra modified by salt acid WD(HCl) and nitrogen acid WD(HNO3). The adsorption kinetics, influence reaction, temperature and kind of carbon were determined using static methods. The adsorption of chromium (VI) onto all activated carbons was most efficient at pH 2. The time of adsorption balance for carbon WD(HCl) was 2.5 h and for carbon WDA 4.5 h. The influence of carbon modification and temperature on the effectiveness of adsorption of hexavalent chromium was determined on the basis of the Freundlich adsorption isotherm. The research showed that the adsorption capacity of Cr(VI) increased with the increasing temperature of the solution. The most efficient adsorbent in static conditions was found on WD-ekstra modified by HCl. The adsorbent applied in dynamic conditions as the filtration bed (v = 2 m/h, time of retention TR = 420 s, initial concentration C0 = 1 mg/dm3), it removed chromium (VI) from water very effectively. Adsorption capacities after exhaustion of the bed were obtained at PeWD (HCl) = 4.35 mg/g. On the basis of executed research, chromium ions were successfully eliminated onto modified carbon WD(HCl) that makes its employment capabilities in the systems purification of water.

Adsorption of Hexavalent Chromium and Divalent Lead Ions on the Nitrogen-Enriched Chitosan-Based Activated Carbon

“…The highly positive charge of the surface of AC strengthen the electrostatic forces between the AC and the Cr(VI) ions. By increasing the pH of the solution, the protonated surface of Ch-ACs decreases gradually and the OH − anion increases in the solution, thus an adsorption competition occurs between the anions (OH − , HCrO 4 − and CrO 4 2− ) leading to a reduction in the efficiency of the Cr(VI) ion removal [ 23 , 28 ].…”

“…In this study, it was found that, at the beginning, the adsorption on Ch-ACs was fast and high for both studied heavy metal ions and this is due to the availability of pores on its surface. After some time, the adsorption decreased due to the desorption process that happens in the solution with agitation time and then increased again up to its maximum adsorption (see Figure S7 ) [ 25 , 28 ]. Figure S8 shows the equilibrium time needed for both Cr(VI) and Pb(II).…”

“…This study targeted the removal of Cr(VI) and Pb(II) ions using ACs produced from the Ch biomass. Cr(VI) ions is known to be 100 times more toxic than Cr(III) and this is due to its high water solubility, easy penetrability through cell membrane, mobility, oxidation, and carcinogenic properties [ 23 , 28 , 29 , 30 ]. Pb(II) ions are present in many industrial processes [ 31 ] and are also very toxic and cause damage to human brain, liver, kidney, and reproductive system and can unfavorably affect brain functions.…”

Synergistic effect of pistachio shell powder and nano-zerovalent copper for chromium remediation from aqueous solution

“…These biomass have poor adsorption and/or recovery for Cr(VI). On the other hand zeolites and activated charcoal show poor surface adsorption for Cr(VI) oxoanions, due to the characteristic electrostatic surface negative charge (Jorfi et al 2017;Puszkarewicz and Kaleta 2019;Vaid et al 2014).…”

Special Issue on Functional Materials in Water and Wastewater Treatment/Soil Remediation

“…Another article by Kim et al [8] reported the application of alginate-coated iron hydroxide for the removal of Cu(II) and phosphate. Puszkarewicz and Kaleta [9] presented research on the adsorptive properties of activated carbon for the removal of chromium (VI) from a water solution. Sun et al [10] also reported the synthesis of a weakly basic polyacrylic anion exchanger, D311, via N-alkylation with 1-bromopropane to effectively remove nitrate from an aqueous solution.…”