in 0.1 M ionic strength aqueous solution at 120 for the following: 2,4-dihydroxy4'-nitroazobenzene (I), 2,4-dihydroxy-4'-sulfonateazobenzene (II), and p-(2hydroxy-l-naphthylazo) benzenesulfonic acid (III). The reported values of k231 were 4O X 105, 3.6 X 105, and 3.6 X 106 M-1 sec-1. They attributed the much lower values of k23, for these acids than the value3 k23, 2 X 109 M-1 sec-1 kn,' for th...

Azo dyes are used in abundance in several industries like textile, printing, paper, plastic, cosmetics, paints, etc. Extensive discharge of such dyes in adjacent water bodies has raised much environmental concern. Azo dyes are toxic to living organisms and their genotoxic and carcinogenic potentials are intensified on being released as mixtures. In the recent years, various microorganisms have ...

Four novel azo disperse dyes based on 1-4-bromobenzyl-4-phenylpiperazine were synthesized in two steps, using alkylation and azo coupling reactions. Chemical structure of the dyes was characterized and confirmed by the Ultraviolet Visible UV-Visible, Fourrier Transform Infrared FT-IR, Proton Nuclear Magnetic Resonance 1H NMR and Carbon Nuclear Magnetic Resonance 13C NMR analyses. The solvatochr...

The photoinduced alignment of a liquid crystal (LC) on films of azo dyes was studied for the liquid crystal display applications. In order to improve the alignment stability of the photoaligned dye (SD-1), the azo-dye derivative with polymerizable terminal groups was synthesized (SDA-1). The films of SDA-1 exhibit good photoalignment properties and ultraviolet stability after thermal polymeriza...

Under anaerobic conditions the sulfonated azo dye Mordant Yellow 3 was reduced by the biomass of a bacterial consortium grown aerobically with 6-aminonaphthalene-2-sulfonic acid. Stoichiometric amounts of the aromatic amines 6-aminonaphthalene-2-sulfonate and 5-aminosalicylate were generated and excreted into the medium. After re-aeration of the culture, these amines were mineralized by differe...

A simple and rapid analytical method for the determination of trace levels of five sulphonated and azo sulphonated reactive dyes: Cibacron Reactive Blue 2 (C-Blue, trisulphonated dye), Cibacron Reactive Red 4 (C-Red, tetrasulphonated azo dye), Cibacron Reactive Yellow 2 (C-Yellow, trisulphonated azo dye), Levafix Brilliant Red E-4BA (L-Red, trisulphonated dye), and Levafix Brilliant Blue E-4BA ...

The biosorption of three reactive azo dyes (red, black and orange II) found in textile effluents by inactive mycelium of Cunninghamella elegans has been investigated. It was found that after 120 hours of contact the adsorption led to 70%, 85%, 93% and 88% removal of reactive orange II, reactive black, reactive red and a mixture of them, respectively. The mycelium surface was found to be selecti...

UNLABELLED BACKGROUND A series of some novel arylazo pyridone dyes was synthesized from the corresponding diazonium salt and 6-hydroxy-4-phenyl-3-cyano-2-pyridone using a classical reaction for the synthesis of the azo compounds. RESULTS The structure of the dyes was confirmed by UV-vis, FT-IR, 1H NMR and 13C NMR spectroscopic techniques and elemental analysis. The solvatochromic behavior ...