Adsorption Characteristics of Heavy Metal Ions on Granular Zeolite (Faujasite: 15.2-91.0%) from Shirasu Volcanic Ash by Column Method

A novel crosslinking modification of β-chitosan and successfully analyzed its fast adsorption characteristics for different heavy metal ions in highly acidic environments.

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

Gels ◽

10.3390/gels7030112 ◽

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.

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Adsorption of Heavy Metal Ions with Magnetic Carbon-Coated Iron Nanoparitcles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.490-495.3049 ◽

2012 ◽

Vol 490-495 ◽

pp. 3049-3053 ◽

Cited By ~ 4

Author(s):

Jin Shan Pang ◽

Ai Hua Deng ◽

Ling Bo Mao ◽

Jin Chen ◽

Xiao Jun Peng ◽

...

Keyword(s):

Heavy Metal ◽

Metal Ions ◽

Heavy Metal Ions ◽

Iron Nanoparticles ◽

Adsorption Property ◽

Acid Solutions ◽

Iron Particles ◽

Adsorption Characteristics ◽

Carbon Coated ◽

Magnetic Carbon

Magnetic carbon-coated iron nanoparitcles were employed as adsorbent to study the adsorption characteristics of some metal ions, such as Cr, Ni, Cu, Pb, Zn. The effect of solution conditions such as pH, amounts of adsorbent, the co-existent ions was investigated. The results show that adsorption property of carbon-coated iron particles to heavy metal ions is improved at the condition of treated by H2O2, and at pH 8-9.5, Cr、Ni、Cu、Pb and Zn were retained on 30mg carbon-coated iron nanoparticles after shaking 3 min, and could be eluted by acid solutions(pH=1~2).

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

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1056.16 ◽

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+.

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