Tailoring electronic configurations in adsorptive sites for the enhancement of As(V) removal from groundwater

2019 ◽  
Vol 20 (3) ◽  
pp. 828-836
Author(s):  
Kaixun Tian ◽  
Jing Xiao ◽  
Jian Shen ◽  
He Zhao
Keyword(s):  
Heavy Metal ◽  
Charge Transfer ◽  
Arsenic Removal ◽  
Metal Removal ◽  
Rapid Development ◽  
Control Sample ◽  
Electronic Configuration ◽  
Fine Tuning ◽  
Aqueous Environment ◽  
Adsorption Performance

Abstract In the past few decades, heavy metal pollution, such as As(V), has become an important issue for aqueous environment safety. For reasons of practical feasibility and cost-effectiveness, adsorption has been widely used in the water treatment and reuse community, with rapid development of adsorbents. However, the precise control of the electronic configuration of the adsorbents' sites to enhance adsorption performance is largely unexplored. In this study, to demonstrate the effect of electronic configuration on adsorption performance, we synthesized granular activated carbon (GAC) supported Fe-based hydroxides adsorbents by varying the valence state in transition metals. Furthermore, the adsorbents are characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM) to identify surface structure and morphological properties. Adsorptive performance studies show that the adsorption capacity and arsenic removal efficiency of Fe(II)-GAC are twice those of Fe(III)-GAC, as a matter of charge transfer between adsorbents and cationic pollution (such as Fe-O and As species). Finally, PO43− was selected as a control sample to confirm the rationality of the removal mechanism. Collectively, fine-tuning of the electronic configuration from charge transfer will not only benefit heavy metal removal channels, but also supply fundamental information for adsorbents design for organics removal.

scholarly journals Enhanced Adsorptive Bioremediation of Heavy Metals (Cd2+, Cr6+, Pb2+) by Methane-Oxidizing Epipelon

2020 ◽  
Vol 8 (4) ◽  
pp. 505 ◽  
Author(s):  
Muhammad Faheem ◽  
Sadaf Shabbir ◽  
Jun Zhao ◽  
Philip G Kerr ◽  
Nasrin Sultana ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Methane Oxidation ◽  
Metal Removal ◽  
Heavy Metal Removal ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Aqueous Environment ◽  
Type I ◽  
Methane Concentrations

Cadmium (Cd), chromium (Cr) and lead (Pb) are heavy metals that have been classified as priority pollutants in aqueous environment while methane-oxidizing bacteria as a biofilter arguably consume up to 90% of the produced methane in the same aqueous environment before it escapes into the atmosphere. However, the underlying kinetics and active methane oxidizers are poorly understood for the hotspot of epipelon that provides a unique micro-ecosystem containing diversified guild of microorganisms including methane oxidizers for potential bioremediation of heavy metals. In the present study, the Pb2+, Cd2+and Cr6+ bioremediation potential of epipelon biofilm was assessed under both high (120,000 ppm) and near-atmospheric (6 ppm) methane concentrations. Epipelon biofilm demonstrated a high methane oxidation activity following microcosm incubation amended with a high concentration of methane, accompanied by the complete removal of 50 mg L−1 Pb2+ and 50 mg L−1 Cd2+ (14 days) and partial (20%) removal of 50 mg L−1 Cr6+ after 20 days. High methane dose stimulated a faster (144 h earlier) heavy metal removal rate compared to near-atmospheric methane concentrations. DNA-based stable isotope probing (DNA-SIP) following 13CH4 microcosm incubation revealed the growth and activity of different phylotypes of methanotrophs during the methane oxidation and heavy metal removal process. High throughput sequencing of 13C-labelled particulate methane monooxygenase gene pmoA and 16S rRNA genes revealed that the prevalent active methane oxidizers were type I affiliated methanotrophs, i.e., Methylobacter. Type II methanotrophs including Methylosinus and Methylocystis were also labeled only under high methane concentrations. These results suggest that epipelon biofilm can serve as an important micro-environment to alleviate both methane emission and the heavy metal contamination in aqueous ecosystems with constant high methane fluxes.

scholarly journals The green, ultrafine cellulose-based porous nanofibrous membranes for efficient heavy metal ion removal through incorporation of chitosan by various electrospinning ways

2022 ◽  
Author(s):  
Qiushi Li ◽  
Ganmao Su ◽  
Ronggang Luo ◽  
Guanben Du ◽  
Linkun Xie ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Active Sites ◽  
Metal Removal ◽  
Copper Ions ◽  
Core Shell ◽  
Adsorption Effect ◽  
Adsorption Sites ◽  
Adsorption Performance ◽  
The Core ◽  
Nanofibrous Membranes

Abstract The rapid global industrialization worsens the contamination of heavy metals in aquatic ecosystems on the earth. In this study, the green, ultrafine cellulose-based porous nanofibrous membranes for efficient heavy metal removal through incorporation of chitosan by the conventional and core-shell electrospinning ways were firstly obtained. The relations among parameters of electrospun solution, micro-morphology and porosity for nanofibers, the variation of chemical active sites and adsorption performance of biocomposite nanofibrous membranes for conventional and core-shell electrospinning as well as the adsorption effect factors of copper ions including initial concentration, pH of solution and interaction time were comprehensively investigated. The results show that the average diameter for conventional and core-shell ultrafine nanofibers at 50% chitosan and 30% chitosan loading can achieve 56.22 nm and 37.28 nm, respectively. The core-shell cellulose acetate/chitosan (CA/CS) biocomposite nanofibrous membranes induced the surface aggregation of copper ions to impede the further adsorption. The more uniform distribution for chemical adsorption sites can be obtained by the conventional single-nozzle electrospinning than by the core-shell one, which promotes the adsorption performance of copper ions and decreases the surface shrinkage of nanofibrous membranes during adsorption. The 30% CS conventional nanofibrous membranes at the pH=5 aqueous solution showed the optimum adsorption capacity of copper ions (86.4 mg/g). The smart combination of renewable biomass with effective chemical adsorptive sites, the electrospinning technology with interwoven porous structure and the adsorption method with low cost and facile operation shows a promising prospect for water treatment.

scholarly journals Filler-Modified Castor Oil-Based Polyurethane Foam for the Removal of Aqueous Heavy Metals Detected Using Laser-Induced Breakdown Spectroscopy (LIBS) Technique

Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 903 ◽  
Author(s):  
M. Iqhrammullah ◽  
Marlina ◽  
R. Hedwig ◽  
I. Karnadi ◽  
K. H. Kurniawan ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Polyurethane Foam ◽  
Castor Oil ◽  
Heavy Metal Ions ◽  
Metal Removal ◽  
Heavy Metal Removal ◽  
Laser Induced Breakdown Spectroscopy ◽  
Breakdown Spectroscopy ◽  
Adsorption Performance ◽  
Laser Induced Breakdown

The use of polymeric material in heavy metal removal from wastewater is trending. Heavy metal removal from wastewater of the industrial process is of utmost importance in green/sustainable manufacturing. Production of absorbent materials from a natural source for industrial wastewater has been on the increase. In this research, polyurethane foam (PUF), an adsorbent used by industries to adsorb heavy metal from wastewater, was prepared from a renewable source. Castor oil-based polyurethane foam (COPUF) was produced and modified for improved adsorption performance using fillers, analyzed with laser-induced breakdown spectroscopy (LIBS). The fillers (zeolite, bentonite, and activated carbon) were added to the COPUF matrix allowing the modification on its surface morphology and charge. The materials were characterized using Fourier-transform infrared (FTIR), scanning electron microscopy (SEM), and thermal gravimetry analysis (TGA), while their adsorption performance was studied by comparing the LIBS spectra. The bentonite-modified COPUF (B/COPUF) gave the highest value of the normalized Pb I (405.7 nm) line intensity (2.3), followed by zeolite-modified COPUF (Z/COPUF) (1.9), and activated carbon-modified COPUF (AC/COPUF) (0.2), which indicates the adsorption performance of Pb2+ on the respective materials. The heavy metal ions’ adsorption on the B/COPUF dominantly resulted from the electrostatic attraction. This study demonstrated the potential use of B/COPUF in adsorption and LIBS quantitative analysis of aqueous heavy metal ions.

scholarly journals Characteristics of iron oxide rust prepared by peracetic acid and its removal of heavy metals in water

2020 ◽  
Vol 158 ◽  
pp. 04005
Author(s):  
Sunyu Jung ◽  
Soon-Ho Park
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Iron Oxide ◽  
Residence Time ◽  
Peracetic Acid ◽  
Arsenic Removal ◽  
Metal Removal ◽  
Removal Rate ◽  
Heavy Metal Removal ◽  
Average Pore

Fe2O3 is an especially promising material for water purification as it shows high heavy metal adsorption capacity. However, the high cost of commercial Fe2O3 makes it difficult to be widely used in developing countries. Herein, we probe the heavy metal removal performance of iron oxide rust. Rust was grown on iron nails in a controlled manner using peracetic acid (CH3CO3H), a safe and environment-friendly oxidizer. Arsenic was selected as an example of a heavy metal contaminant in this study. XRD and EDS analysis revealed that the iron oxide prepared with peracetic acid was nearly amorphous Fe2O3. Amorphous iron oxide is reported to show higher reactivity than crystalline iron oxide. The BET specific surface area of prepared Fe2O3 is 71 m2/g, which is larger than that of commercial Fe2O3, and the average pore diameter is 73 Å. Oxidized nails are highly effective for removing heavy metals: about 90% of 1ppm arsenic in water was removed at the residence time of 20 minutes, and the removal rate of 90% is maintained after 10 back-to-back arsenic removal experiments at the same residence time. Iron oxide prepared in this study can remove, per 1 cm2, up to 0.114 mg of arsenic.

A magnetic activated sludge for Cu(ii) and Cd(ii) removal: adsorption performance and mechanism studies

2019 ◽  
Vol 43 (46) ◽  
pp. 18062-18071 ◽  
Author(s):  
Yingrui Liu ◽  
Qingwei Yang ◽  
Rui Feng ◽  
Weiying Xu ◽  
Liangguo Yan ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Activated Sludge ◽  
Metal Removal ◽  
Heavy Metal Removal ◽  
Adsorption Performance ◽  
Performance And Mechanism

In the present study, a novel magnetic activated sludge (MAS) was successfully synthesized and applied for heavy metal removal.

scholarly journals Synthesis, characterization and heavy metal removal efficiency of nickel ferrite nanoparticles (NFN’s)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Waheed Ali Khoso ◽  
Noor Haleem ◽  
Muhammad Anwar Baig ◽  
Yousuf Jamal
Keyword(s):  
Heavy Metals ◽  
Nickel Ferrite ◽  
Contact Time ◽  
Metal Removal ◽  
Heavy Metal Removal ◽  
Ferrite Nanoparticles ◽  
Batch Adsorption ◽  
Aqueous Environment ◽  
Human Beings ◽  
Nickel Ferrite Nanoparticles

AbstractThe heavy metals, such as Cr(VI), Pb(II) and Cd(II), in aqueous solutions are toxic even at trace levels and have caused adverse health impacts on human beings. Hence the removal of these heavy metals from the aqueous environment is important to protect biodiversity, hydrosphere ecosystems, and human beings. In this study, magnetic Nickel-Ferrite Nanoparticles (NFNs) were synthesized by co-precipitation method and characterized using X-Ray Diffraction (XRD), Energy Dispersive Spectroscopy (EDS) and Field Emission Scanning Electronic Microscopy (FE-SEM) techniques in order to confirm the crystalline structure, composition and morphology of the NFN’s, these were then used as adsorbent for the removal of Cr(VI), Pb(II) and Cd(II) from wastewater. The adsorption parameters under study were pH, dose and contact time. The values for optimum removal through batch-adsorption were investigated at different parameters (pH 3–7, dose: 10, 20, 30, 40 and 50 mg and contact time: 30, 60, 90, and 120 min). Removal efficiencies of Cr(VI), Pb(II) and Cd(II) were obtained 89%, 79% and 87% respectively under optimal conditions. It was found that the kinetics followed the pseudo second order model for the removal of heavy metals using Nickel ferrite nanoparticles.

Sign in / Sign up

Export Citation Format

Share Document