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Conference

2019

Molecular Structure and Spectroscopic Studies of Some Diazo Dyes Compounds using DFT Method

2019-12
2019 First International Conference of Intelligent Computing and Engineering (ICOICE)
Diazo dyes compounds have a variety biological and industrial applications. In this study, the molecular structures and the spectroscopic parameters of three synthesized diazo dyes 1–3 were computed using a Density Functional Theory DFT method with the B3LYP/6-311++G(d.p), The results indicate that all three diazo dyes are preferred thermodynamically. Compound 3 has a higher value of entropy and more negative values of heat formation and Gibb's free energy as compared to the other dyes. The FTIR spectra of 2 and 3 show that the nitro functional groups at ortho positions appear at lower symmetrical stretching frequencies. At all, there is a good agreement with the experimental results. On the other hand, the energy gap decreases in this order 2, 3 and 1, also, the FTIR spectrum of compound 1 shows a lower symmetrical stretching frequency of the nitro functional group at the para position.

Electrochemical Degradation of Alizarin Black Dye in Aqueous Medium Using Fe/Al Electrode

2019-04
ICOASE2019
This work investigates the electro-catalytic degradation of alizarin black dye in an electrochemical cell using Fe as anode and Al as cathode. The influence of initial dye concentration, effect of salt, pH, change of temperature and effect change of applied voltage have been studied in addition, the influence of semiconductor dose has studied as well. In the current work roughly total removal of 70 mg/L of dye was 16 minute only. The results were shown that effect of both electrolyte concentration and applied voltage was positive if combined together and the rate of degradation in acidic medium was the best for degradation of Alizarin black dye.
2018

Mechanism and Thermodynamic Parameters of Paternὸ-Büchi Reaction of Benzene and Furan: DFT Study

2018-10
2018 International Conference on Advanced Science and Engineering (ICOASE)
The Paternὸ-Büchi reaction of benzene with benzaldehyde and furan with furfural were studied theoretically. The mechanism was investigated using Density Functional Theory (DFT). It was found that the final product of the benzene reaction is oxetane 3, while in the case of furan the oxetane 6 is unstable and goes through oxetane ring opening. The target of this article was to study the reaction mechanism and calculate the thermodynamic parameters of the reactions. The oxetane 3 formed was found to be stable with reaction energy of -120 kcal/mol. However, the oxetane 6 was found to be less stable with reaction energy 21 kcal/mol which tends to produce more stable product 7 through the oxetane ring opening. In addition, the molecular orbitals were calculated and analyzed for all the intermediates, oxetanes and final products.

Stereoselectivity and Regioselectivity of the Cycloaddition Dimerization of allyl 3-(2-pyridyl) acrylate and allyl 3-(2-pyrryl) acrylate: DFT Calculations

2018-08
IOP Conference Series: Materials Science and Engineering
A theoretical study of the photochemical dimerization of allyl 3-(2-pyridyl) acrylate and allyl 3-(2-pyrryl) acrylate is reported. The reactions gave dimers with high regioselectivity and stereoselectivity through [2+ 2] cycloaddition mechanism. All calculations were computed by density functional theory method, B3LYP, in conjunction with the 6-31G (d) basis set. Conformation analysis, geometric parameters and IR spectrum for the target dimers were also studied. Conformation 2 of allyl 3-(2-pyridyl) acrylate and conformation 9 for allyl 3-(2-pyrryl) acrylate were found to be the most stable structures among the different conformations. Vibration frequencies and IR absorption intensities were calculated for the conformers 2 and 9 using the same computational method. In addition, thermodynamic parameters for the reactions of most stable conformations were analysed. The HOMO and LUMO molecular orbitals and the …
2017

Heterogeneous Photodegradation of Dye Using Two Different Types of Local Clays as a Catalysts

2017-04
ICEEE2015
Photocatalytic degradation of Acid Alizarin Black S (AAB) dye (C.I. 21725) was studied, at different operating conditions, in aqueous solution using UV light in the presence of two types of local clay (B1 and B2) as a catalysts. The operating conditions were catalysts dosage (10, 30 and 50 mg), initial concentration of AAB dye (10, 20 and 30 mg/L), pH (2, 4, 6, 9 and 11) and UV light intensity (6 and 12 watt). It was found that the increasing of catalyst dosage enhanced the removal percent of dye. Clays (B1 and B2) exerted positive effects on the AAB removal whilst the initial AAB concentration negatively affected its removal. It was also found that the removal efficiency of AAB significantly depend on pH value. In high pH values removal percent increase, while a reversed trend was observed in low pH value. The result shown that removal percent of dye decreased when 6 watt lamp used instead 12 watt lamp. The data proved that B2 was more efficient than B1 for removing AAB dye. B1 and B2 clays were analysed by X-Ray fluorescence to determine the metal oxides in clays.

FENTON DEGRADATION OF FAST GREEN DYE

2017-04
2nd INTERNATIONAL SCIENTIFIC CONFERENCE – UNIVERSITY OF ZAKHO
The degradation of commercial textile dye named fast green (FG) was investigated by Fenton reagent under different operating conditions in an aqueous solution. The operating conditions were amount of hydrogen peroxide (0.05, 0.1 and 0.15 mL), pH (2-12) and concentration of ferrous ion (10, 20 and 30 mg). The initial rate of degradation was affected by the concentration of Fenton reagents [Fe(II) and H2O2 solution]. The rate of degradation enhanced as the concentration of ferrous ion increased. As the ferrous ion concentration increased from 10 to 30 mg, the removal percent was increased from 73% to 89%, respectively, at 25 min of reaction time. Also, the removal percent of FG increased from 74 % to 81 % as the amount of H2O2 increased from 0.05 to 0.15 mL, respectively, at 25 min of reaction time. it was also found that at pH 3 removal percent reach maximum value with 91.8%. The kinetic study of FG degradation was also studied in this work and the results indicated that the degradation kinetics of FG followed the first-order kinetic.

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