Calcined Corncob-Kaolinite Combo as New Sorbent for Sequestration of Toxic Metal Ions From Polluted Aqua Media and Desorption

Abstract

This study investigated a new area of improving the adsorption capacity of clay using corn cob as an alternative means of clay modification to the more expensive and complicated chemical treatment techniques. Kaolinite Clay (KC), Calcined corncob-kaolinite Combo (CCKC), and Corncob (CC) adsorbents were utilized. The adsorbents were characterized by Fourier Transform-Infrared (FT-IR) Spectroscopy, Scanning Electron Microscopy (SEM), X-ray fluorescence spectroscopy, and Brunauer-Emmett-Teller (BET) surface area analyzer. Batch adsorption methodology was used to investigate the effect of pH, initial metal concentration, adsorbent dose, and contact time on adsorption of Pb (II) and Cd (II). A slight increase in BET surface area of 29.31 m2/g for CCKC from 14.12 m2/g for raw KC was achieved. The trend of metal adsorption on the adsorbents was in the order CC>CCKC>KC. The Langmuir isotherm was found to present the best fit for the unmodified adsorbents while the Freundlich was applicable for CCKC indicating multilayer heterogeneous surface. The pseudo second order kinetic model was found to be suitable in the kinetic analysis. Thermodynamic studies revealed a spontaneous physical adsorption process of metal ions on CCKC. The combo adsorbent showed highest percentage desorption (>70%) of Cd and Pb ions in both acid and basic media compared to the other adsorbents. The results of the study established the efficiency of calcined corn cob kaolinite combo as suitable adsorbent for metal ions.

Abstraction of arsenic(III) on activated carbon prepared from Dialium guineense seed shell: kinetics, isotherms and thermodynamic studies

“…Prominent C=O stretching vibrations were observed at 1606 and 1520 cm −1 while the C=C of alkenes at 1438 cm −1 . The primary alcoholic C-O stretching was indicated by the band at 1032 cm −1 [14]. The FTIR spectrum of the activated carbon showed significant band changes from the raw biosorbent and the disappearance of most of the organic bands which indicate the successful production of activated carbon from the biosorbent.…”

“…Adsorption is often used because it is very simple and cost effective [12]. Numerous adsorbents have been used for the sequestration of heavy metals from polluted water such as activated carbon, agricultural biomass materials, nanoparticles, activated alumina, sandy soils, hydrous zirconium oxide, lanthanum-loaded-silica gel, hematite, goethite, magnetite, feldspar, clays and metal-loaded coral limestone [13][14][15][16][17][18]. Most of these adsorbents are expensive and difficult to regenerate.…”

Adsorption Properties of Tropical Soils from Awka North Anambra Nigeria for Lead and Cadmium Ions from Aqueous Media

“…The fast removal of both metal ions on the five adsorbents initially was due to the presence of abundant active sites on the soils. The abundant active sites were occupied as time progressed attaining saturation leading to no further sequestration [36]. The sorption was initially controlled by the rapid diffusion of lead and cadmium from the solution to the surface of the tropical soils.…”

“…The intraparticle diffusion can be estimated by using the model equation to elaborate the diffusion mechanism of lead and cadmium on the tropical soils expressed as [36,51]:…”

Nano platelets kaolinite for the adsorption of toxic metal ions in the environment

“…Lead(II) ions have been released to the environment through phosphate fertilizers, electrical wiring, manufacturing batteries, air conditioning tubing, plumbing, electroplating, and pigments (Huang et al, 2019;Khan et al, 2017;Kong et al, 2019;Tomei and Mosca Angelucci, 2019). Removal of Pb(II) ions from aqueous and wastewater was developed using un modified and modified kaolin clay such as tripolyphosphate-impregnated kaolinite clay (Unuabonah et al, 2007), HCl treatedkaolin (Drweesh et al, 2016), illitic clay (Ozdes et al, 2011), 3-amino propyl trimethoxy silanemodified kaolinite (Fatimah, 2018), modified and unmodified kaolinite clay (Jiang et al, 2009(Jiang et al, ,2010Sari and Tuzen, 2014;Sdiri et al, 2016;Khan and Singh, 2010;Omar and Al-Itawi, 2007;Shahmohammadi et al, 2011;Etoh et al, 2015;Malima et al, 2018), nanoscale zero-valent iron (Zhang et al, 2010), raw clay and broken-brick waste (El-Shahat and Shehata, 2013), polyphosphate-modified kaolinite clay (Amer et al, 2010), Polyvinyl alcohol-modified kaolinite clay (Unuabonah et al, 2008), Nano illite/smectite clay (Yin et al,2018), bentonite clay (Al-Jlil, 2018), kaolinite and metakaloinite (Essomba et al, 2014), and calcined corncobkaolinite (Chukwuemeka-Okorie et al, 2018). The present research work aimed to modify raw Jordanian kaolin clay to Nano-platelets kaolinite for use as an efficient adsorbent for Pb (II) ions from aqueous solutions.…”