• Advances in environmental research
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• v.3 no.4
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• pp.293-306
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• 2014

The present study primarily focuses on the evaluation of the comparative effect of chemical coagulation and ultrasonication for elimination of aromatic amines (AAs) present in anaerobically pretreated textile wastewater containing different types of dyes including azo dyes. Color and COD reduction was also monitored at the optimized conditions. The production of AAs was measured spectrophotometrically in the form of total aromatic amines (TAAs) and also verified with high performance liquid chromatography (HPLC) selectively. A composite coagulant, magnesium chloride (MC) aided with aluminium chlorohydrate (ACH) in an equal ratio (MC + ACH) was utilized during the coagulation process, which yielded 31% of TAAs removal along with 85% of color and 52% of COD reduction. At optimized power (200 W) and sonication time (5 h), an appreciable TAAs degradation efficiency (85%) was observed along with 51% color reduction and 62% COD removal using ultrasonication. The chromatographic data indicate that sulphanilic acid and benzidine types of aromatic amines were produced after the reductive cleavage of utilized textile dyes, which were effectively mineralized after ultrasonication. The degradation followed the first order kinetics with a correlation coefficient ($R^2$) of 0.89 and a first-order kinetic constant (k) of $0.0073min^{-1}$.

• Journal of Korean Society on Water Environment
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• v.22 no.2
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• pp.333-341
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• 2006

The concept for the decolorization in biological dye wastewater treatment systems is based on anaerobic treatment, for the reductive cleavage of the dyes' azo linkages, in combination with aerobic treatment, for the degradation of the products from azo dye cleavage, aromatic amines. Batch tests were conducted to examine the conditions and the factors affecting biological treatment of dye wastewater. From the tests, the removal efficiencies of organics and colors of dyeing wastewater were improved to $COD_{Cr}$ 27% and color 9% by injecting 10% of the domestic wastewater as a cosubstrate, and $COD_{Cr}$ 30%, color 22% with 30% injection of domestic wastewater. Therefore it was proved that decolorization efficiency is demonstrated with domestic wastewater as a cosubstrate. The analysis of aromatic amines in wastewater showed that decolorization was achieved by cometabolism while aromatic amines were produced by cleavage of azo bonds under anaerobic conditions and these products were removed in an aerobic tank subsequently.

• Elastomers and Composites
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• v.43 no.1
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• pp.31-38
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• 2008

Sonochemical reaction of fullerene oxides, $[C_{70}(O)_n](n\geq1)$ with several aromatic amines such as 4-nitroaniline, 3-nitroaniline, and 4-isopropylaniline, in the presence of $FeCl_3$ were investigated under ultrasonic irradiation. This method is applicable to a wide variety of aromatic amines especially ring deactivated, to afford the corresponding cleavage products under mild conditions. The aminated fullerenes were confirmed by MALDI-TOF-MS and UV-vis spectra.

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.281-283
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• 1993

Aromatic nitro compounds are selectively hydrogenated to the corresponding amines in high yields at room temperature and atmospheric pressure using BER-Pd catalyst without affecting ketone, ether, ester, nitrile or chloro groups also present. Especially the nitro group in 4-nitrobenzyl alcohol, methyl 4-nitrobenzyl ether and N-N-dimethyl 4-nitrobenzylamine is selectively hydrogenated with this catalyst to give the corresponding amines without hydrogenolysis of benzylic groups. And aromatic nitro compound can be reduced selectively in the presence of aliphatic nitro compound.

• Journal of Food Hygiene and Safety
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• v.14 no.4
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• pp.386-396
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• 1999

Commonly eaten fish, meat and other protein-containing foods show some level of mutagenic activity following normal cooking such as broiling, frying, grilling, roasting etc. The main food mutagens found in cooked products are“heterocyclic aromatic amines”. Several of them have been shown to be carcinogenic in rodent and suggested to be relevant for human cancer etiology. This review summarizes the chemistry, formation, occurrence and toxicity of food-borne heterocyclic aromatic amines. Factors that influence the formation of them are also discussed with special emphasis on dietary factors. From a health safety point of view, it is desirable to estimate the intake of heterocyclic amines via foods, and reduce or prevent the formation of food mutagens.

• Journal of the Korean Society of Tobacco Science
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• v.28 no.2
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• pp.152-157
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• 2006

A new procedure has been developed for the quantitation of aromatic amines in mainstream cigarette smoke. Two solid-phase extraction (SPE) clean up steps, using a different retention mechanisms, are required to process the samples. The first step used a cation-exchange cartridge, followed by a second step that used a cartridge with a hydrophobic retention character. The aromatic amines eluted from the second SPE cartridge are derivatized with pentafluoropropionic anhydride. This new method have advantages over other reported techniques, being sensitive, robust, and easily automated. The detection limits were ranged from 0.12 ng/mL for 1-aminonaphthalene to 0.16 ng/mL for 3-aminobiphenyl and the recoveries were from 97 to 106%. Compared with other reports for analysis of 2R4F reference cigarette, this method shows a close analytical data and good repeatability.

• Journal of Hydrogen and New Energy
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• v.8 no.3
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• pp.131-135
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• 1997

Aromatic primary amines were prepared by the catalytic hydrogenation of aromatic nitro compounds in a benzene solution over 50 mg of 10 % palladium on charcoal at a room temperature under 45 psi. This paper describes a study on the catalytic hydrogenation of nitrobenzene-$d_5$, $^{15}N$-labelled nitrobenzene, and 4'-nitrobenzo-15-crown-5, respectively. The infrared absorption spectra exhibited a characteristic N-H stretching vibrations at 3450 and $3350cm^{-1}$. The results suggest that the non-readily available aromatic amines would be commercially produced by catalytic hydrogenation because of its good yield and little by-product formation.

• Elastomers and Composites
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• v.42 no.1
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• pp.1-8
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• 2007

The cleavage of fullerene oxides with several aromatic amines such as 4-nitroaniline, 3-nitroaniline, 4-isopropylaniline in the present of $FeCl_3$ occurred under ultrasonic irradiation in air at $25{\sim}43^{\circ}C$. The aminated fullerenes were confirmed by MALDI-TOF-MS and UV-vis spectra.

• Journal of Photoscience
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• v.6 no.3
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• pp.117-121
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• 1999

Photoinduced electron transfer of C60 has been studied by the laser photolysis measuring the transient absorption bands in near-IR region. The electron transfer aromatic amines via the triplet state of C60 is confirmed by the decay of the transient absorption bands of the triplet state of C60 and the rise of the anion radical of C60 and the cation radicals of amines. The rate and efficiency of electron transfer are strongly affected by the donor ability of amines and polarity of solvents. Back electron-transfer kinetics is also strongly affected by the solvent polarity.

• Bulletin of the Korean Chemical Society
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• v.33 no.5
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• pp.1785-1787
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• 2012