scholarly journals Diacetate Cellulose-Silicon Bionanocomposite Adsorbent for Recovery of Heavy Metal Ions and Benzene Vapours: An Experimental and Theoretical Investigation

2021 ◽  
Vol 12 (3) ◽  
pp. 2862-2880
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Quantum Chemical ◽  
Heavy Metal Ions ◽  
Density Functional ◽  
Basis Sets ◽  
Chemical Calculation ◽  
Quantum Chemical Analysis ◽  
The Density Functional Theory ◽  
Adsorption Capacitance

The diacetate cellulose-silicon bionanocomposite adsorbent (DACSBNC) was first introduced to recover heavy metal ions and benzene vapors. The adsorption thermodynamics of heavy metal ions and benzene vapors on the DACSBNC was first investigated by the adsorption-calorimetric, X-ray, and theoretical methods. The observed results confirmed that (i) the adsorption capacitance of DACSBNC for cadmium (II), mercury (II), and lead (II) ions were accounted for 12.23, 13.87, and 31.40 mg/g, respectively; (ii) the sorption capacitance of DACSBNC for benzene vapors was 0.5618 mmol/g. The quantum chemical calculation was also carried out on the density functional theory (DFT) using the 6-31G (d, p)/B3LYP basis sets in Gaussian 09. The results of the quantum chemical analysis support the experimental results.

A DFT-BASED ANALYSIS OF ADSORPTION PERFORMANCE OF CU2+ AND ZN2+ ON DEFECTIVE GRAPHENE FOR THE APPLICATION OF POLLUTING METAL IONS TREATMENT

2021 ◽  
pp. 2150061
Author(s):  
TAO CHEN ◽  
LIBAO AN ◽  
YAN ZHANG ◽  
XIAOTONG JIA
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Density Functional ◽  
Chemical Adsorption ◽  
Functional Theory ◽  
Adsorption Performance ◽  
The Density Functional Theory ◽  
Orbit Analysis ◽  
Defective Graphene

The density functional theory has been used to study the adsorption performance of polluting Cu[Formula: see text] and Zn[Formula: see text] ions on defective graphene. Compared to intrinsic graphene, the adsorption distance between defective graphene and Cu[Formula: see text]/Zn[Formula: see text] decreases greatly, and the adsorption energy and charge transfer amount increases significantly. The calculation of charge density demonstrates that clear hybridization happens between defective graphene and Cu[Formula: see text]/Zn[Formula: see text] ions, suggesting the formation of chemical adsorption. The frontier orbit analysis shows that defective graphene has greater electrical sensitivity after adsorbing Cu[Formula: see text]/Zn[Formula: see text] ions. Therefore, defective graphene could be a potential material for the treatment of contaminating heavy metal ions.

The adsorption of divalent heavy metal ions on (8,0) carbon nanotubes: The first-principles study

2020 ◽  
Vol 34 (32) ◽  
pp. 2050368
Author(s):  
Z. Zhu ◽  
L. An ◽  
T. Chen ◽  
X. Jia
Keyword(s):  
Carbon Nanotubes ◽  
Heavy Metal ◽  
Metal Ions ◽  
First Principles ◽  
Industrial Wastewater ◽  
Heavy Metal Ions ◽  
Density Functional ◽  
Physical Adsorption ◽  
Functional Theory ◽  
Sensing Material

In order to explore new ways to detect and remove heavy metal ions from industrial wastewater, the first-principles method based on density functional theory has been used to investigate the performance of carbon nanotubes (CNTs) in adsorbing divalent heavy metal ions which include Zn[Formula: see text], Cu[Formula: see text], Pb[Formula: see text] and Sn[Formula: see text]. Results show that the adsorption of Zn[Formula: see text] on CNTs is weak and only physical adsorption forms between them. However, for Cu[Formula: see text], Pb[Formula: see text] and Sn[Formula: see text], the final adsorption distance with CNTs is greatly decreased, and the adsorption energy and charge transfer amount with CNTs are significantly increased. In addition, the charge density of Cu[Formula: see text], Pb[Formula: see text] and Sn[Formula: see text] overlaps effectively with that of CNTs. These indicate the formation of strong chemisorption between these ions and CNTs. Therefore, CNTs could be used as a sensing material to detect and remove Cu[Formula: see text], Pb[Formula: see text] and Sn[Formula: see text] from wastewater. The research provides theoretical guidance for the application of CNTs in heavy metal ions treatment.

scholarly journals CALCULATION OF THE ELECTRONIC STRUCTURE OF SOME EPOXY MOLECULES BY THE DFT METHOD

2021 ◽  
pp. 32-34
Author(s):  
V. A. Babkin ◽  
D. S. Andreev ◽  
E. S. Titova ◽  
A. V. Ignatov ◽  
R. O. Boldyrev ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Electronic Structure ◽  
Quantum Chemical Calculation ◽  
Quantum Chemical ◽  
Density Functional ◽  
Dft Method ◽  
Chemical Calculation ◽  
Functional Theory ◽  
The Density Functional Theory

In this work, we performed a quantum-chemical calculation of some epoxy molecules: 1,2-epoxy-butene, 1,2-epoxy-2-methylpropane, 1,2 epoxyethane by the density functional theory DFT. An optimized geometric and electronic structure of these compounds is obtained. It was found that the studied epoxides belong to the class of very weak СH-acids (pKa = 28-30).

scholarly journals Molecular Modeling of Acidic Treated PSTM-3T Polymer for Removal of Heavy Metal Ions by Experimental and Computational Studies

2014 ◽  
Vol 2014 ◽  
pp. 1-6
Author(s):  
Natsagdorj Narantsogt ◽  
Gunchin Burmaa ◽  
Adiya Perlee-Oidov ◽  
Nyamdorj Shurkhuu ◽  
Namsrai Javkhlantugs
Keyword(s):  
Molecular Structure ◽  
Heavy Metal ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Density Functional ◽  
Acidic Solution ◽  
Ph Value ◽  
Density Functional Theory Method ◽  
Structure Change ◽  
Sorption Efficiency

The synthesized poly[N,N′-bis(3-silsesquioxanilpropyl)-thiocarbamide] (PSTM-3T) was used and the surface morphology and microstructure of it were analyzed by scanning electron microscopy with energy dispersive spectrometer (SEM/EDS). The molecular structure change of the PSTM-3T polymer of the PSTM-3T after treatment by acidic solution with different pHs was revealed using FT-IR experiments andab initiocalculations with density functional theory method. The sorption efficiency of the heavy metal ions depends on the molecular structure change of PSTM-3T after treatment of different pH aqueous solutions. After the treatment of acidic solution (pH = 2) of PSTM-3T, the polymer formed the tautomer state to increase the sorption efficiency for chromate ion. For the increment of pH value for acidic solution, the PSTM-3T polymer was dissociated to increase the sorption efficiency for copper ion.

scholarly journals DFT calculations and electrochemical studies on azulene ligands for heavy metal ions detection using chemically modified electrodes

2018 ◽  
Vol 8 (1) ◽  
pp. 73-85
Author(s):  
Amalia Stefaniu ◽  
Maria-Daniela Pop ◽  
Georgiana-Luiza Arnold ◽  
Liviu Birzan ◽  
Lucia Pintilie ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Density Functional ◽  
Computational Study ◽  
Modified Electrodes ◽  
Chemically Modified Electrodes ◽  
Point Energy ◽  
Chemically Modified ◽  
Oxidation Potentials

A computational study on three related derivatives of 5-[(azulen-1-yl)methylene]-2-thioxoimidazolidin-4-one was conducted using density functional theory by calculating a series of molecular descriptors and properties of their optimized geometries (electrostatic and local ionization potentials, molecular frontier orbitals, etc.). Thermodynamic properties (zero-point energy, enthalpy, constant volume heat capacity, entropy and Gibbs energy) for these derivatives have been calculated and related to ligands electrochemical behavior. Reduction and oxidation potentials have been correlated to their calculated energy levels for LUMO and HOMO orbitals. Chemically modified electrodes based on these derivatives have been tested in view of heavy metal ions recognition, and their detection limits have been correlated to the calculated values of electron affinity.

Effects of heavy metal ions on N-nitrosodimethylamine (NDMA) formation

RSC Advances ◽  
2016 ◽  
Vol 6 (74) ◽  
pp. 70474-70479
Author(s):  
Yameng Liu ◽  
Yongdong Liu ◽  
Rugang Zhong ◽  
Bin Peng ◽  
Henry F. Schaefer, III
Keyword(s):  
Density Functional Theory ◽  
Heavy Metal ◽  
Metal Ions ◽  
Metal Complexes ◽  
Heavy Metal Ions ◽  
Density Functional ◽  
Functional Theory

The mechanism of NDMA formation as affected by heavy metal complexes [MONO]+ (M = Cd, Pb, Hg) was investigated using density functional theory (DFT). Three possible NDMA formation pathways are discussed.

Sign in / Sign up

Export Citation Format

Share Document