STUDY OF SORBENT OBR -1 CHARACTERISTIC FOR TERTIARY TREATMENT OF DRINKING WATER FROM HEAVY METAL IONS AND ORGANIC SUBSTANCES

2013 ◽  
Vol 3 (1) ◽  
pp. 46-50
Author(s):  
G. B ABUOVA ◽  
L. V BORONINA ◽  
V. I KIChIGIN
Keyword(s):  
Quantum Chemical ◽  
Heavy Metal Ions ◽  
Chemical Method ◽  
Theoretical Study ◽  
Organic Substances ◽  
Tertiary Treatment ◽  
Structural Units ◽  
High Sorption Capacity ◽  
Water Ph ◽  
High Sorption

High sorption capacity of OBR-1 in relation to the studied substances is determined. It is shown that the desorption (elution) of the studied organic and nonorganic compounds from OBR-1 doesnt practically occur in conditions of getting treated water (pH, temperature, concentration). The article describes the theoretical study of organic and nonorganic compounds at particular structural units of OBR-1 using the up-to-date quantum-chemical method that makes it possible to represent the experiment and theorybased models of adsorption units.

Facile Fabrication of Poly(Acrylic Acid-Co-Acrylamide) Hydrogel with 4A Molecular Sieve for Removal of Heavy Metal Ions

2015 ◽  
Vol 1092-1093 ◽  
pp. 852-855
Author(s):  
Xiao Dan Lv ◽  
Zheng Yang Wang ◽  
Jian Hui Zhang ◽  
Zi Shu Chen ◽  
Wei Feng Cao ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Acrylic Acid ◽  
Mechanical Strength ◽  
Metal Ions ◽  
Molecular Sieve ◽  
Heavy Metal Ions ◽  
High Sorption Capacity ◽  
High Sorption ◽  
Facile Fabrication ◽  
Poly Acrylic Acid

A novel hydrogel was successfully synthesized through doping 4A molecular sieve (4A-MS) into poly (acrylic acid-co-acrylamide) and used for the removal of Cu2+, Ni2+, Cd2+and Pb2+in the solution. The composite hydrogel all exhibited high sorption capacity (SC) and high elution percentage (EP) for the four above heavy metal ions. Simultaneously, the water uptake (WU) of the hydrogel was dramatically decreased and the mechanical strength of the absorbent hydrogel was improved with increasing 4A-MS content.

scholarly journals Sorption properties of wool

2004 ◽  
Vol 58 (7-8) ◽  
pp. 315-321
Author(s):  
Maja Radetic ◽  
Dragan Jocic ◽  
Petar Jovancic ◽  
Ljubinka Rajakovic
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Industrial Effluents ◽  
Fibre Surface ◽  
Developed Countries ◽  
Sorption Properties ◽  
Wool Fibre ◽  
High Sorption Capacity ◽  
High Sorption

Strict ecological legislation, especially in highly developed countries, imposed requirements for the purification of industrial effluents and the need for efficient oil clean up after sea and inland water spills. Although numerous processes have been developed, the application of sorbents is still one of the most efficient methods to remove heavy metal ions, dyes and crude oil from water. Recently, special attention was paid to sorbents based on natural fibres. A review of studies concerning the sorption properties of wool is presented in this paper. The presence of various functional groups on the wool fibre surface contributes to the efficient sorption of heavy metal ions and dyes. A hydrophobic, scaly surface and fibre crimp strongly influence the high sorption capacity of wool for oil. Wool has great sorption potential even as a recycled material. Accordingly, it can be used as a viable substitute to commercially available synthetic sorbents that show poor biodegradab ility.

THEORETICAL STUDY ON HYDROLYSIS MECHANISM OF β-PHOSPHOLACTAMS

2006 ◽  
Vol 05 (spec01) ◽  
pp. 421-431 ◽  
Author(s):  
LINGJUAN YU ◽  
DACHENG FENG ◽  
MAOXIA HE ◽  
RUI LI ◽  
ZHENGTING CAI
Keyword(s):  
Quantum Chemical ◽  
Continuum Model ◽  
Chemical Method ◽  
Theoretical Study ◽  
Polarizable Continuum Model ◽  
Energy Barriers ◽  
Stepwise Mechanism ◽  
Hydrolysis Mechanism ◽  
Polarizable Continuum ◽  
Hydrolysis Of

The neutral hydrolysis mechanisms of a simple β-phospholactam with and without water-assisted reaction have been studied by using quantum chemical method at HF/6-31G**, MP2/6-31G** and B3LYP/6-31G** levels, respectively. The reaction can proceed by two different mechanisms: concerted and stepwise. There are two pathways in stepwise, i.e. pathway a and b, and the energy barriers of them are close. The energy barriers of water-assisted hydrolysis of β-phospholactam are obviously lower than those of no-water-assisted hydrolysis system. The energy barriers of stepwise mechanism are much lower than those of the concerted pathway in both cases. The solvent effects have been considered by means of a polarizable continuum model. The hydrolysis mechanism of β-phospholactam with that of the β-lactam and β-sultam was compared.

Solvation of ions by dipolar aprotic solvents and water. A CNDO/2 study

1985 ◽  
Vol 50 (11) ◽  
pp. 2493-2508 ◽  
Author(s):  
Petr Kyselka ◽  
Zdeněk Havlas ◽  
Ivo Sláma
Keyword(s):  
Binary Mixtures ◽  
Quantum Chemical ◽  
Chemical Method ◽  
Molecular Structures ◽  
Dimethyl Sulphoxide ◽  
Ternary Mixtures ◽  
Aprotic Solvents ◽  
Quantum Chemical Method ◽  
Solvation Of Ions ◽  
Dipolar Aprotic Solvents

Solvation of Li+, Be2+, Na+, Mg2+, and Al3+ ions has been studied in binary mixtures with dimethyl sulphoxide, dimethylformamide, acetonitrile and water, and in ternary mixtures of the organic solvents with water. The CNDO/2 quantum chemical method was used to calculate the energies of solvation, molecular structures and charge distributions for the complexes acetonitrile...ion (1:1, 2:1, 4:1), dimethyl sulphoxide...ion (1:1), dimethylformamide...ion (1:1), and acetonitrile (dimethyl sulphoxide, dimethylformamide)...ion...water (1:1:1).

scholarly journals Dynamics of Oxidation of Reduced Forms of CO2 under Electrochemical and Open-Сircuit Conditions on Polycrystalline Pt in H2CO3

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 274
Author(s):  
Alexander V. Smolin ◽  
Мikhail N. Mikhailov ◽  
Aleksey F. Gadzaov ◽  
Leonid M. Kustov
Keyword(s):  
Quantum Chemical ◽  
Preliminary Analysis ◽  
Oxidation Reaction ◽  
Density Functional ◽  
Oxidation Process ◽  
Open Circuit ◽  
Organic Substances ◽  
Oxidation Of Co ◽  
Reduced Forms

The problem of identifying correlations between catalytic and electrocatalytic processes is one of the fundamental problems of catalysis among “simple” organic substances, and the oxidation of CO and rCO2 is of great interest, since CO and CO2 are considered in pairs both during catalytic and electrocatalytic transformations. In the case of electrocatalysis, this analysis is important in the study of fuel cells. In this paper, we studied the correlation between the oxidation of reduced forms of CO2 (rCO2) under potentiodynamic-galvanoctatic electrochemical and open-circuit conditions of measurements on polycrystalline (pc)Pt in H2CO3. Periodic oscillations are revealed at the oxidation of Had and rCO2 on (pc)Pt. Quantum chemical calculations were carried out on the Pt13 cluster in order to identify the mechanisms of the rCO2 oxidation reaction. The correspondence in the energy parameters of the oxidation process of rCO2 under open-circuit conditions and electrochemical conditions is shown. The preliminary analysis of the system using density functional (DFT) calculations is carried out and the most stable systems that are based on Pt13 are found, namely rOH-Pt13-(CO)n, rOH-Pt13-(COH) and rOH-Pt13-(rCOOH). OH• species was chosen as the most likely candidate for the role of the oxidant for rCO2. Preliminary calculations for the expected reactions were carried out, and the optimal PES is revealed.

scholarly journals Prebiotic Route to Thymine from Formamide—A Combined Experimental–Theoretical Study

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2248
Author(s):  
Lukáš Petera ◽  
Klaudia Mrazikova ◽  
Lukas Nejdl ◽  
Kristyna Zemankova ◽  
Marketa Vaculovicova ◽  
...  
Keyword(s):  
Formic Acid ◽  
Quantum Chemical ◽  
Prebiotic Chemistry ◽  
Theoretical Study ◽  
Reaction Pathway ◽  
Hydrolysis Product ◽  
Current Paper ◽  
Reaction Conditions ◽  
Chemical Modeling ◽  
Chemistry Research

Synthesis of RNA nucleobases from formamide is one of the recurring topics of prebiotic chemistry research. Earlier reports suggest that thymine, the substitute for uracil in DNA, may also be synthesized from formamide in the presence of catalysts enabling conversion of formamide to formaldehyde. In the current paper, we show that to a lesser extent conversion of uracil to thymine may occur even in the absence of catalysts. This is enabled by the presence of formic acid in the reaction mixture that forms as the hydrolysis product of formamide. Under the reaction conditions of our study, the disproportionation of formic acid may produce formaldehyde that hydroxymethylates uracil in the first step of the conversion process. The experiments are supplemented by quantum chemical modeling of the reaction pathway, supporting the plausibility of the mechanism suggested by Saladino and coworkers.

Sign in / Sign up

Export Citation Format

Share Document