scholarly journals Fast and Reliable Synthesis of Melanin Nanoparticles with Fine-Tuned Metal Adsorption Capacities for Studying Heavy Metal Ions Uptake

2021 ◽  
Vol Volume 14 ◽  
pp. 101-111
Author(s):  
Eman R Darwish ◽  
Haitham Kalil ◽  
Wafa Alqahtani ◽  
Sayed MN Moalla ◽  
Nasser M Hosny ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Metal Adsorption ◽  
Adsorption Capacities ◽  
Melanin Nanoparticles

Adsorption of Heavy Metal Ions by Chelate-Fiber Prepared by Chemical Surface Modification

2011 ◽  
Vol 308-310 ◽  
pp. 178-181
Author(s):  
Xin Liang Liu ◽  
Li Jun Wang ◽  
Yong Li Chen ◽  
Nan Chen ◽  
Shuang Fei Wang
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Optimal Process ◽  
Order Model ◽  
Chemical Surface ◽  
Adsorption Capacities ◽  
Chemical Surface Modification ◽  
Pseudo Second Order ◽  
Mechanism Of Sorption

The bagasse fibers were activated by alkalize and etherified. 1,2-ethanediamine and carbon disulfide were used to modify the etherify fiber to get the chelate-fiber contained sulfur and nitrogen. The FTIR was used to characterize the xanthated aminating-fiber (XAF). The mechanism of sorption properties for heavy metal ions were studied. As the results shown, the optimal process to prepare the XAF was that the reaction time, concentration of NaOH and dosage of CS2 was 60min, 12% and 2mL, respectively. The chelate-fiber containing sulfur and nitrogen possessed high adsorption capacities for Cu(II) and the mechanism of sorption fitted the pseudo-second-order model well.

scholarly journals Chemically stable magnetic nanoparticles for metal adsorption and solid acid catalysis in aqueous media

2014 ◽  
Vol 2 (16) ◽  
pp. 5751-5758 ◽  
Author(s):  
T. Okada ◽  
Y. Takeda ◽  
N. Watanabe ◽  
T. Haeiwa ◽  
T. Sakai ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Magnetic Nanoparticles ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Acid Catalysis ◽  
Solid Acid ◽  
Aqueous Media ◽  
Metal Adsorption ◽  
Solid Acid Catalysis

Magnetically collectable and reusable particles for concentrating heavy metal ions and solid acid catalysis in aqueous media were developed.

scholarly journals Adsorptive Removal of Heavy Metal Ions, Organic Dyes, and Pharmaceuticals by DNA–Chitosan Hydrogels

Gels ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 112
Author(s):  
Kayee Chan ◽  
Kohki Morikawa ◽  
Nobuyuki Shibata ◽  
Anatoly Zinchenko
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Organic Dyes ◽  
Double Helix ◽  
Adsorptive Removal ◽  
Adsorption Characteristics ◽  
Adsorption Capacities ◽  
Hydrogel Matrix ◽  
Dna Double Helix

DNA–chitosan (DNA–CS) hydrogel was prepared by in situ complexation between oppositely charged DNA and chitosan polyelectrolytes via electrostatic cross-linking to study its adsorption characteristics. The DNA–chitosan hydrogel matrix contains (i) cationic (NH3+) and anionic (PO4–) sites for electrostatic binding with ionic species, (ii) -OH and -NH2 groups and heteroaromatic DNA nucleobases for chelation of heavy metal ions, and (iii) DNA double-helix for recognition and binding to small organic molecules of various structures and polarities. DNA–CS hydrogels efficiently bind with Hg2+, Pb2+, Cd2+, and Cu2+ metal cations of significant environmental concern. Adsorption capacities of DNA–CS hydrogels for studied metal ions depend on hydrogel composition and pH of solution and reach ca. 50 mg/g at neutral pHs. Hydrogels with higher DNA contents show better adsorption characteristics and notably higher adsorption capacity to Hg2+ ions. Because of the co-existence of cationic and anionic macromolecules in the DNA–CS hydrogel, it demonstrates an affinity to both anionic (Congo Red) and cationic (Methylene Blue) dyes with moderate adsorption capacities of 12.6 mg/g and 29.0 mg/g, respectively. DNA–CS hydrogel can also be used for adsorptive removal of pharmaceuticals on conditions that their molecules are sufficiently hydrophobic and have ionogenic group(s). Facile preparation and multitarget adsorption characteristics of DNA–CS hydrogel coupled with sustainable and environmentally friendly characteristics render this system promising for environmental cleaning applications.

scholarly journals Biosorption of copper(II) and chromium(VI) by modified tea fungus

2012 ◽  
pp. 335-342 ◽  
Author(s):  
Marina Sciban ◽  
Jelena Prodanovic ◽  
Radojka Razmovski
Keyword(s):  
Heavy Metal ◽  
Aqueous Solutions ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Acid Modification ◽  
Adsorption Ability ◽  
Batch Mode ◽  
Chromium Vi ◽  
Adsorption Capacities ◽  
Tea Fungus

The tea fungus was found to have good adsorption capacities for heavy metal ions. In this work it was treated with HCl or NaOH at 20?C or 100?C, with the aim to improve its adsorption ability. The sorption of Cu(II) and Cr(VI) ions from aqueous solutions by raw and treated tea fungus was investigated in the batch mode. The largest quantity of adsorbed Cu(II), of about 55 mg/g, was achieved by tea fungus modified with NaOH at 100?C. For Cr(VI), the largest quantity of adsorbed anions, of about 58 mg/g, was achieved by the adsorbent modified with NaOH at 20?C. It was shown that acid modification of tea fungus biomass was not effective.

Adsorption of Pb2+, Cu2+ and Cr3+ on Yongnian Bentonite

2014 ◽  
Vol 1056 ◽  
pp. 16-19
Author(s):  
Shu Li Ding ◽  
Dan Dan Hou ◽  
Bo Hui Xu ◽  
Yu Zhuang Sun
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Constant Temperature ◽  
Langmuir Isotherm ◽  
Heavy Metal Ions ◽  
Adsorption Process ◽  
Isotherm Model ◽  
Adsorption Characteristics ◽  
Adsorption Capacities ◽  
Langmuir Isotherm Model

The Bentonite from Yongnian is Ca-Bentonite, Montmorillonite Content 52%, Colloidal Value 57ml/15g, Eca2+/CEC 53.60%. the Adsorption Characteristics of Pb2+, Cu2+ and Cr3+ onto Bentonite under Conditions of Constant Temperature and Ph have been Studied. the Results Show that the Adsorption Capacities of Heavy Metal Ions onto Bentonite from Yongnian Follow the Order of Pb2+> Cu2+> Cr3+. it is Found that the Adsorption Process of Bentonite Accords with the Langmuir Isotherm Model. the Maximum Adsorption of 3 Kinds of Metal Ions onto Bentonite is in Order of Cr3+>Cu2+>Pb2+.

scholarly journals Solubility and Selectivity Effects of the Anion on the Adsorption of Different Heavy Metal Ions onto Chitosan

Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2482 ◽  
Author(s):  
Janek Weißpflog ◽  
Alexander Gündel ◽  
David Vehlow ◽  
Christine Steinbach ◽  
Martin Müller ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Adsorption Capacity ◽  
Heavy Metal Ions ◽  
Batch Experiments ◽  
Sorption Mechanism ◽  
Iron Cobalt ◽  
Cobalt Nickel ◽  
Adsorption Capacities ◽  
Nickel Copper

The biopolymer chitosan is a very efficient adsorber material for the removal of heavy metal ions from aqueous solutions. Due to the solubility properties of chitosan it can be used as both a liquid adsorber and a solid flocculant for water treatment reaching outstanding adsorption capacities for a number of heavy metal ions. However, the type of anion corresponding to the investigated heavy metal ions has a strong influence on the adsorption capacity and sorption mechanism on chitosan. In this work, the adsorption capacity of the heavy metal ions manganese, iron, cobalt, nickel, copper, and zinc were investigated in dependence on their corresponding anions sulfate, chloride, and nitrate by batch experiments. The selectivity of the different heavy metal ions was analyzed by column experiments.

scholarly journals Characteristics of Heavy Metal Ion Adsorption by Silty Mudstones in Coal Mine Goafs

Geofluids ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-17
Author(s):  
Qiang-ling Yao ◽  
Ze Xia ◽  
Chuan-jin Tang ◽  
Liu Zhu ◽  
Wei-nan Wang ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Coal Mine ◽  
Heavy Metal Ions ◽  
Equilibrium Concentration ◽  
Western China ◽  
Water Volume ◽  
Isothermal Adsorption ◽  
Adsorption Capacities ◽  
Mine Wastewater

Coal mine goafs can be used to store and purify mine water; therefore, they are important for mitigating the environmental impact of mining on ecologically fragile areas in Western China. Coal gangue in goafs can reduce turbidity, suspended matter, total hardness, and chemical oxygen demand (COD) in mine wastewater. Because gangue in goaf areas is rich in clay minerals, they serve as ion exchange sites. We investigated the adsorption of heavy metal ions by silty mudstones in the Ulan Mulun mine. The adsorption kinetics and isothermal adsorption characteristics of four heavy metal ions, i.e., Pb(II), Cd(II), Cr(III), and Mn(II), were investigated using batch experiments. Under a pH of 6.75 and temperature of 20°C, the adsorption capacity of silty mudstone particles (<74 μm) was 6.3012 g, 1.5701, 1.2571, and 1.3729 mg/g for Pb(II), Cd(II), Cr(III), and Mn(II), respectively. Based on the experimental results, quantitative relationships between the adsorption quantity per unit of rock surface and the equilibrium concentration of heavy metals in solution were developed using Langmuir, Freundlich, and D–R equations. The relationships were used to obtain the equilibrium concentration of the solution. Finally, the ratio of the f value of the water-rock contact area in the goaf to the water volume was calculated and analyzed. The f value was inversely proportional to the average vertical opening of gaps between gangues in the goaf. The adsorption rate functions for Pb(II), Cd(II), Cr(III), and Mn(II) in the goaf were obtained, and the corresponding adsorption capacities were calculated. The adsorption capacities were controlled by the f value and adsorption properties of the gangue. These results can be used in future studies on mine wastewater treatment.

scholarly journals Heavy Metal Ion Adsorption Properties of Methacrylamidocysteine-Containing Porous Poly(Hydroxyethyl Methacrylate) Chelating Beads

2002 ◽  
Vol 20 (7) ◽  
pp. 607-617 ◽  
Author(s):  
Adil Denizli ◽  
Bora Garipcan ◽  
Sibel Emir ◽  
Süleyman Patir ◽  
Ridvan Say
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Metal Ion ◽  
Heavy Metal Ions ◽  
Metal Removal ◽  
Ph Value ◽  
Heavy Metal Removal ◽  
Ion Concentration ◽  
Heavy Metal Ion ◽  
Adsorption Capacities

Details of the adsorption performance of poly(2-hydroxyethylmethacrylate–methacrylamidocysteine) [p(HEMA–MAC)] beads towards the removal of heavy metal ions from aqueous solution were studied. The metal-complexing ligand and/or co-monomer MAC was newly synthesized from methylacrylochloride and cysteine. Spherical beads of average size 150–200 mm were obtained by the radical suspension polymerization of MAC and HEMA conducted in an aqueous dispersion. The p(HEMA–MAC) beads obtained had a specific surface area of 18.9 m2/g. p(HEMA–MAC) beads were characterized by swelling studies, FT-IR spectroscopy and elemental analysis. Such beads with a swelling ratio of 72%, and containing 3.9 mmol MAC/g, were used for heavy metal removal studies. The adsorption capacities of the beads for selected metal ions, i.e. CdII, AsIII, CrIII, HgII and PbII, were investigated in aqueous media containing different amounts of these ions (10–750 mg/l) and at different pH values (3.0–7.0). The adsorption rate was fast in all cases. The maximum adsorption capacities of the p(HEMA–MAC) beads were 1058.2 mg/g for CdII, 123.4 mg/g for AsIII, 199.6 mg/g for CrIII, 639.1 mg/g for PbII and 1018.6 mg/g for HgII. On a molar basis, the following affinity order was observed: CdII > HgII > CrIII > PbII >AsIII. The adsorption capacity of the MAC-incorporated beads was affected significantly by the pH value of the aqueous medium. The adsorption of heavy metal ions from artificial wastewater was also studied. In this case, the adsorption capacities were 52.2 mg/g for CdII, 23.1 mg/g for CrIII, 83.4 mg/g for HgII, 62.6 mg/g for PbII and 11.1 mg/g for AsIII at an initial metal ion concentration of 0.5 mmol/l. The chelating beads could be regenerated easily with a higher effectiveness by 0.1 M HNO3. These features make p(HEMA–MAC) beads potential candidates for heavy metal ion removal at high capacity.

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