Removal of cadmium (Cd-II) from aqueous solution using gas industry-based adsorbent

Abstract

The present study is to determine the potential of gas industry sludge as a low-cost adsorbent for the removal of cadmium from aqueous solution. The batch experiments were conducted to optimize pH, contact time, adsorbent dose and initial metal ion concentration. The experiments were optimized at pH 5, contact time 60 min and an adsorbent dose of 0.75 g/100 ml with constant agitation at the room temperature. The result of batch experiment was further discussed for the removal of cadmium from adsorbent. The adsorption data were correlated with Freundlich and Langmuir isotherms to know the interaction of sludge adsorbent with cadmium. High value of regression coefficient (R 2 > 0.95) indicated that the adsorption data are fitted well with both Langmuir and Freundlich isotherms. The adsorption capacity of 25 mg/g was found to be quite good for removal of the cadmium from aqueous solution. Desorption efficiency showed highest removal with HCl (42.83%); followed by HNO 3 (38.26%), EDTA (37.73%) and H 2 SO 4 (36.83%). The removal and desorption efficiency of the gas industry-based adsorbent was found to be comparable and even more suitable than the chemically modified adsorbents. The present study provides a low-cost and environmentally friendly adsorbent, which can be used as an alternative for the treatment of wastewater.

Heavy metal removal from industrial effluent using bio-sorbent blends

“…(9) where C o is the initial metal concentration (mg/L) and b is the Langmuir constant (L/mg). If R L > 1, then the adsorption is unfavorable; if R L = 1, then the adsorption is linear; if 0 < R L < 1, then the adsorption is favorable; and if R L = 0, it is irreversible [11].…”

“…Adsorption has been an important area of interest in the recent years, with majority latest research focused on identifying low-cost adsorbents [9]. Research work is also being done to synthesize new adsorbents with some recent advances in novel adsorbents which include using activated carbon synthesized from peanut shell [10], alizarin red-S-loaded amberlite IRA-400 anion exchange resin [11], starch/SnO 2 nanocomposite [12], Fe 3 O 4 nanocomposites [13], MOF (metal organic framework)-based composites [14,15], nickel ferrite bearing nitrogen-doped mesoporous carbon (NiFe 2 O 4 -NC) [16], nanocomposite cation exchanger sodium dodecyl sulfate acrylamide Zr(IV) selenite (SDS-AZS) [17] for removing toxic heavy metals. Such adsorbents are specially tailored to give them favorable properties like high adsorption capacity, regeneration capability, high surface area, mechanical and thermal stability [18,19].…”

Trophic status and its regulating factor determination at the Rewalsar Lake, northwest Himalaya (HP), India, based on selected parameters and multivariate statistical analysis

“…However, the obnoxious materials that stay in water bodies for a longtime period bring changes in the physiochemical characteristics as well as the natural scenario of the lakes [5]. The Himalayan lakes are under stress due to mismanaged human activities, which increase nutrients and pollution in terms of heavy metals toxicity and bacterial contamination [6][7][8]. The management and preservation of the lakes at present have become a great challenge for environmentalists and managers [5,9].…”

Nanoadsorbants for the Removal of Heavy Metals from Contaminated Water: Current Scenario and Future Directions

“…The probable reason mentioned was the agglomeration of the adsorbent at higher concentrations which inhibits the adsorption process due to surface adsorption decrease. In fact, in another study an increase in the removal efficiency of Cd 2+ ions (83% to 89%) was observed when the concentration of gas industry-based adsorbent was increased from 0.25-1.25 g/100 ML [34]. In gas phase, it was found that no agglomeration takes place, so the adsorption only depends on the amount of adsorbent added.…”