Many foods contain Yellow Azo dyes in varying proportions, due to food ...
reactions all of the Yellow Azo dyes, particularly among asthmatics and those
with ...
Schmeiser, and D.H. Phillips, â Metabolic activation of environmental contaminant 3- nitrobenzanthrone by human acetyltransferases and sulfotransferases,â.
application in pharmaceutical, cosmetic, food, dyeing/textile industry ..... ty. photochromic, transition-state-analogue inhibitors of cysteine and serine proteases, J.
nr 12/2012 ⢠tom 66. ⢠1303. Azo dyes â biological ..... Microbiol. 1998, 64, 2788. Schliephake K., Mainwaring D. E., Lonergan G. T., Jones I. K., Baker W. L.: 20.
Figure 1.2 The effluent of textile industry- China (Wood, 2010). ...... constructed wetland for engineering purposes was constructed in New York, North ... manual aimed primarily for separate houses (Wallace, 2004). ...... Fur Praktische Chemie,.
Feb 6, 2012 - to a cold suspension of p-phenylenediamine and/or benzidine. (1.74 mmol) in concentrated HCl (6 ml) with stirring at low temperature for 15 ...
of azo dye (tartrazine and allura red) biosorption onto S. platensis .... The fit quality was measured ac- .... suggested that allura red biosorption onto S. platensis.
Mar 2, 2015 - Index Termsâ Azo Dye, Sulfa drag, determination of metals ... symmetrically azo compounds which are derived from Sulfa compounds. As well ...
Apr 19, 2005 - In the literature, there is a large number of papers reporting on the decolorization of azo dyes; ..... Maximo, C., and M. Costa-Ferreira. 2004.
Sep 5, 2016 - Decolorization of Disperse Blue (R16), Disperse Yellow (D4), and Reactive Red Synozol (R4) dyes which were used singly and in mixture was ...
dearomatization is achieved by ring reduction and also includes other unique reactions such as carboxylation, reductive dehydroxylation and addition reactions, ...
be effective in anaerobic bacterial systems with sulfate. ACKNOWLEDGMENTS. The writers thank Hans-Böckler-Stiftung for the financial support and. Prof.
Abstract Nanosized magnetic Fe3O4 synthesized via sonochemical route was used as a photocatalyst for the degradation of azo dyes, methyl red and congo red ...
May 9, 2016 - Abstract. In the present study, spent Rhizopus arrhizus biomass was used for the removal of six azo dyes from aqueous solutions. The dye ...
medium by drawing 1cm3 medium on UV visible ELICO SL 159 nanodrop spectrophotometer. The percentage decolourization was calculated from the following ...
reaction in non acidic, non corrosive medium using green methodologies. Benign methods of azo dye synthesis includes diazocoupling reaction in solid-.
chloride, N-{4-[(4-Bromophenyl) sulfamoyl] phenyl}-N2-[(4-chlorophenyl) sulfonyl]- .... partially purified by ammonium sulfate precipitation followed by salting out.
Larry D. Claxton,* Debra B. Walsh, James F. Esancy and Harold S. Freeman ..... Prival MJ, Davis VM, Peiperl MD, Bell SJ (1988) . Evaluation of azo food dyes for ...
both LiP and MnP and they have potential to oxidize Mn2+ to Mn3+ at .... Remazol Navy Blue 8.0, 30, -, -, 30 ..... B, Light Navy Blue HEG, Dark Navy Blue H2GP).
Dec 22, 2015 - ppm dye concentration of Disperse Blue (R16), Disperse Yellow (D4), and Reactive Red Synozol (R4) of 49%, 41.5%, and. 15%, respectively ...
Nevertheless, in most cases the products, in particular benzidine-based derivatives, demonstrate an increased toxicity [3,6,7]. For example, the azo dye Direct.
It appears that metabolic ac- tivation is .... Orange RN, Sunset Yellow, Pon- ...... Early observations that reduction products of azo dyes such as FD&C Red no.
Azo Dyes. Aromatic diazonium ions can be trapped (before loss of N. 2. ) by
electron-rich aromatic compounds (e.g., possessing activating groups). NH2. N N
. Cl.
Aromatic Amines Synthesis with Aromatic Diazonium Ions N NH2
N NaNO2/HCl HO N O (nitrous acid)
Nu Nu -N2
diazonium ion
acts like
Some Characteristics of Diazonium Salts 1. Aliphatic diazonium salts are very unstable even at low temperatures and decompose instantly upon formation CH3CH2CH2 N N
CH3CH2CH2
+
N N
2. Aromatic diazonium salts are much more stable due to conjugation with an aromatic ring and decompose only slowly at ice bath temperatures 3. Groups ortho and para to the diazonium salt functionality act to stabilize it 4. Aromatic diazonium salts function as weak electrophiles and will only react with aromatic rings containing strongly activating groups O H
O R
N R R
Azo Dyes Aromatic diazonium ions can be trapped (before loss of N2) by electron-rich aromatic compounds (e.g., possessing activating groups)
O2N
NH2
NaNO2/HCl 0 oC
Cl O2N
an aromatic diazonium salt
N N
4-Nitrobenzenediazonium chloride
4-Nitroaniline
NO2
Cl O2N
N N
OH +
N 2-Naphthol
Para Red
N OH
Azo Dyes Two azo dyes are prepared: para red and one from another naphthol-aromativ amine combination Sodium Nitrite Solution: dissolve NaNO2 (1 g) in H2O (10 mL). This provides enough 10% NaNO2 solution to prepare two azo dyes Aromatic Amine Solution: disolve aromatic amine (250 mg) in 10% HCl (10 mL) Naphthol Solution: dissolve naphthol (250 mg) in 10% NaOH (10 mL) Diazotized Amine Solution: cool the aromatic amine solution to 0 oC and add sodium nitrite solution (5 mL) dropwise with mixing. Allow the solution to stand 2 min Azo Dye Solution: insert a cloth strip into diazotized amine solution, allow to become saturated and add the naphthol solution dropwise
Azo Dyes This procedure is to be used employing 4-nitroaniline and 2-naphthol to prepare para red and a second azo dye using a different combination of amine and naphthol Aromatic Amines
Naphthols OH
O2N
NH2
4-Nitroaniline
2-Naphthol OH
NH2 NO2 2-Nitroaniline
1-Naphthol
Rinse the cloth samples with water to determine color-fastness
Synthesis with Aromatic Diazonium Ions What starting materials are needed to synthesize the following azo compound? O O S
