Direct Orange Research Articles

Rapid biodegradation and decolorization of Direct Orange 39 (Orange TGLL) by an isolated bacterium Pseudomonas aeruginosa strain BCH

A newly isolated novel bacterium from sediments contaminated with dyestuff was identified as Pseudomonas aeruginosa strain BCH by 16S rRNA gene sequence analysis. The bacterium was extraordinarily active and operative over a wide rage of temperature (10-60 degrees C) and salinity (5-6%), for decolorization of Direct Orange 39 (Orange TGLL) at optimum pH 7. This strain was capable of decolorizing Direct Orange 39; 50 mg l(-1) within 45 +/- 5 min, with 93.06% decolorization, while maximally it could decolorize 1.5 g l(-1) of dye within 48 h with 60% decolorization. Analytical studies as, UV-Vis spectroscopy, FTIR, HPLC were employed to confirm the biodegradation of dye and formation of new metabolites. Induction in the activities of lignin peroxidases, DCIP reductase as well as tyrosinase was observed, indicating the significant role of these enzymes in biodegradation of Direct Orange 39. Toxicity studies with Phaseolus mungo and Triticum aestivum revealed the non-toxic nature of degraded metabolites.

Minimization of organic chemical load in direct dyes effluent using low cost adsorbents

The work is carried out to minimize the organic chemical load (unexhausted dye contents) in direct dyes effluent using low cost adsorbents. The studies are made with different direct dyes, i.e. Direct Red 28, Direct Yellow 12, Direct Orange 26 and Direct Blue 1 with various adsorbents. Three different bio/natural materials have been selected as adsorbents. These includes, Sugarcane bagasse pith (SB), Saw dust (SD)—the plant origin products, and Brick powder (BP)—a silica based material obtained from earth's crust on thermal heating. These substances are almost discarded waste products with the possibility of use as adsorbents. Experimental work for the dye removal from the effluent by activated charcoal (AC) has also been carried out and the results are compared with other adsorbents. The amount of unexhausted organic dye present in the effluent is measured as chemical oxygen demand (COD) before and after the treatment. Adsorbent Sugarcane bagasse pith shows good performance as compared to Saw dust and Brick powder. For understanding the behaviour of adsorbents Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) has also been carried out.

Sensory Profile of Mandarin Chilled Juices and Consumers' Acceptability

Chilled mandarin juices from four different commercial brands, two mandarin juices prepared in our pilot plant and two commercial orange juices included for comparative purposes were scored for acceptability by 100 consumers in a unique evaluation session. Independently, a descriptive profile of the same samples was performed by 10 trained assessors, who quantified 29 sensory attributes. Most consumers preferred mandarin juices although a small group (about 10%) found orange juices more acceptable. No differences in acceptability were observed between samples from diluted concentrates and from direct juice, either mandarin or orange. Among sensory attributes, maximum differences between samples were found for color, pulp (aspect and texture), mandarin odor, mandarin taste, bitterness and persistent taste.

Degradation of an Azo Dye by Fenton Type Processes Assisted with UV Irradiation

Organic synthetic dyes are widely produced and used today. Significant losses of organic and inorganic content occurs during the manufacturing and application of dyes and its discharge in the effluent presents a threat to the eco-systems due to general toxicity and resistance to destruction by biological treatment methods. Particularly azo dyes are of special environmental concern due to their degradation products such as aromatic amines, which are considered highly carcinogenic. So, dyes have to be removed from coloured wastewater before discharge. However, traditional treatment methods (adsorption, coagulation/flocculation) mainly transfer the contaminants from wastewater to secondary waste. Therefore, advanced oxidation processes seem to be sustainable and clean technology to decolorize and minimize organic dyes content from wastewater. In this paper, degradation of an azo dye C.I. Direct Orange 39 (DO39) using Fenton type processes (Fe2+/H2O2, Fe3+/H2O2and Fe0/H2O2) has been performed. The molar ratio of Fenton’s type reagents has been varied in the range of 1 : 5 up to 1 : 50 at 0.5 and 1.0 mM concentrations of iron salts and iron powder. Experiments have been conducted for two hours in a batch reactor with magnetic stirring, ambient conditions and pH 3. The process efficiency and formation of degradation by-products have been determined on the basis of results obtained by UV/VIS spectrophotometric, total organic carbon (TOC) and high performance liquid chromatography (HPLC) analyses. The optimal Fenton and Fenton ``like" processes parameters have been applied in the photo reactor, too. It has been observed that simultaneous utilization of UV irradiation with Fenton's and Fenton ``like" reagents increases the degradation of DO39 dye. Degradation of the dye in dilute aqueous solution follows pseudo-first order kinetics. The maximal decolourization of 20 mg L-1 DO39 in water of 93.2% and TOC degradation of 76.9% were obtained using Fe3+/H2O2= 1 : 5 molar ratio. The results indicate that the treatment of DO39 dye wastewater with UV/Fe3 +/H2O2 system was found to be the most efficient.

Use of Beech Wood Sawdust for Adsorption of Textile Dyes

In this research a new efficient adsorbent of dyes is used. Thus, adsorption of some textile dyes from aqueous solution by using an industrial waste lignocellulosic product is studied. Between five dyes tested, three dyes were chosen for testing: Direct Orange 26, Acid Orange 7, Acid Green 20. Kinetics of adsorption and equilibrium isotherm of dyes was investigated using Longmuir and Freundlich models. This study showed that the beech wood sawdust could be employed as low-cost and effective sorbent for the removal of dyes from aqueous solution.

Effect of Ultrasonic Irradiation on the Catalytic Activity and Stability of Goethite Catalyst in the Presence of H2O2 at Acidic Medium

The objective of this research is to examine the effect of ultrasonic irradiation (35 kHz) on the catalytic activity and stability of goethite powder (α-FeOOH) in the presence of H2O2 at pH 3. The catalytic activity of the catalyst was investigated on the decolorization of Direct Orange 39 (DO39) azo dye as a model pollutant, and the stability of the catalyst was examined by measuring contemporary dissolved total iron concentration. The decolorization of dye was strongly enhanced by ultrasonic irradiation on Fenton-like process (α-FeOOH/H2O2). The kinetics of decolorization obeys first-order reaction and the rate constant was found to be 0.0189 min-1. The effect of α-FeOOH and H2O2 (2.5−15 g/L) dosage on the decolorization and iron dissolution was investigated and found to increase the decolorization rate with increasing dosage. However, both dosages did not influence the iron dissolution. The catalytic reusability was investigated in up to four successive cycles, and was found that the catalytic efficiency did not decrease appreciably. The effect of ultrasonic irradiation on the catalyst composition, surface area, pore volume, and pore size has been investigated and discussed in each cycle. The structure of the catalyst before and after four cycles was investigated using X-ray diffraction (XRD), cold-field emission scanning electron microscope (FESEM). The mechanism of degradation was discussed. It is concluded that ultrasonic irradiation in the presence of α-FeOOH and H2O2 is an efficient process and that the goethite is a promising catalyst for the abatement of dye pollutants in wastewater.

Study of interaction between a cationic surfactant and two anionic azo dyes by ion-selective electrode technique and spectrophotometry

Interaction between a cationic surfactant, hexadecyltrimethylammonium bromide (HTAB), and two anionic azo dyes, C.I. Direct Orange 26 (DO26) and Direct Red 16 (DR16) has been investigated using surfactant-selective electrode and spectrophotometry techniques. In ion-selective electrode technique an HTAB surfactant-selective membrane electrode has been used. The electromotive force versus total surfactant concentration has been plotted for the systems of HTAB/DR16 and HTAB/DO26 in 1 × 10 −4 and 1 × 10 −3 mol dm −3 NaBr at 25 °C. The concentrations of free and bound surfactant and also dye–surfactant complex constant, K, could be obtained from the experimental data. The data show that significant binding takes place and the critical concentration associated with the saturation of the dyes with bound surfactant has been determined. The results also indicate that in the DO26/HTAB system, where more hydrophobic dye DO26 is used, the dye–surfactant interaction is stronger than in DR16/HTAB system, which shows the importance of hydrophobic forces in the interaction.

Advanced Oxidation Processes in Azo Dye Wastewater Treatment

The chemical degradation of synthetic azo dyes color index (C.I.) Acid Orange 7, C.I. Direct Orange 39, and C.I. Mordant Yellow 10 has been studied by the following advanced oxidation processes: Fenton, Fenton-like, ozonation, peroxone without or with addition of solid particles, zeolites HY, and NH4ZSM5. Spectrophotometric (UV/visible light spectrum) and total organic carbon measurements were used for determination of process efficiency and reaction kinetics. The degradation rates are evaluated by determining their rate constants. The different hydroxyl radical generation processes were comparatively studied, and the most efficient experimental conditions for the degradation of organic azo dyes solutions were determined.

Self‐curable aqueous polymeric dyes for printing and dyeing applications

AbstractAn epoxy resin (NPES‐904, epoxy equivalent weight is 815) with a repeating unit, n > 4 was selected as a polymer backbone of polymeric dye. Water‐reducible epoxy resin was prepared by a semiesterification of its secondary hydroxy group with succinic anhydride and then dispersed to aqueous phase after it was neutralized with triethylamine. An aqueous polymeric dye was obtained from a ring opening reaction of that epoxy resin with amino group of a direct dye (soluble dye such as C. I. Acid Blue 62, C. I. Direct Orange 39 or C. I. Direct Red 2). These aqueous polymeric dye dispersions carried the average particle sizes between 50 and 90 nm. A polyaziridine was added as a latent curing agent and forming a self‐curable system of aqueous polymeric dye solution, which was stable in aqueous phase when its pH remained above 8.0. This aqueous polymeric dye was self‐cured on drying at ambient temperature and results in the formation of waterproof and solvent‐resistant polymeric dye. These self‐curable polymeric dyes had potential for jet ink printing and dyeing applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1919–1931, 2006

Studies on the interaction of some azo dyes (naphthol red-J and direct orange) with nontronite mineral

The adsorption of two azo dyes, namely naphthol red-J and direct orange, on nontronite mineral was studied as a function of pH and temperature. All the sorption studies were conducted in batch mode. The Langmuir and Freundlich isotherm models were applied. The isotherms are Langmuirian in nature, while the Freundlich equation is only valid over the low concentration range. The adsorption of the two dyes increases with increased temperature and decreases with increased pH. The data have been explained in terms of the area of contact of the dye molecule on the clay platelet vis-à-vis the area per anion exchange site. Estimated area per anion exchange site of the mineral and area associated per anionic dye molecule at nontronite surface was 642 and 454 Å2 for naphthol red-J and 642 and 440 Å2 for direct orange respectively. This has been further supported by X-ray measurements. Thermodynamic parameters of the process were evaluated.

Quantal Response Of Freshwater Shrimp (<i>Desmocaris trispinosa</i>) To Toxicity Of Azo Dyes

The quantal-response of freshwater shrimp (Desmocaris trispinosa) to the toxicity of five azo dyes was studied. Generally, increase in percentage mortality of the organisms was obtained with increases in concentration of the toxicants and exposure time. The median lethal concentration50 (LC50) and median lethal concentration50 (LC50) values were obtained from the concentration-mortality and time-mortality probit graphs, respectively. Based on the LC50 and LT50 values, the dyes were ranked in order of toxicity: Mordant Black 11>Acid Orange 10>Direct Red 28>Direct Orange 31>Direct Red 23. Differences in quantal effect of the toxicants was attributed to their molecular weight, dye content and/or impaired oxygen transfer through the respiratory apparatus of the organisms due to adsorption of the dye molecules on their gill surface. Evidence of bioaccumulation of the toxicants in guts and tissues of the shrimps was obtained and its implication to human health was discussed. KEY WORDS: Toxicity, azo dyes, Desmocaris trispinosa, quantal response, bioaccumulation Global Journal of Environmental Sciences Vol.4(1) 2005: 41-45

Influence of iron on degradation of organic dyes in corona

In this work application of AOPs such as Fenton process, aqueous phase high voltage electrical discharge (corona) and their combination have been studied for colored wastewater treatment. Experiments were conducted on water solutions of four different organic dyes, two azo dyes C.I. Mordant Yellow 10 (MY10) and C.I. Direct Orange 39 (DO39), and two reactive of azo type C.I. Reactive Red 45 (RR45) and C.I. Reactive Blue 137 (RB137). The efficiency of studied AOPs has been estimated on the bases of UV–vis spectrophotometric and TOC measurements. The rate constants in the kinetic model have been determined. Experimental data have been compared with the developed mathematical model.

The Removal of Direct Orange 39 by Pulsed Corona Discharge From Model Wastewater

Untreated wastewater from the dye industry and dyehouses cannot be directly discharged into the environment due to the high content of organic matter and intensive colouration, even with low concentrations of dye. In this paper, the application of a high voltage pulsed electrical discharge in the aqueous phase has been assessed for the dye degradation. Experiments were conducted in a batch reactor using model wastewater of the commercial water-soluble monoazo dye C.I. Direct Orange 39 (DO39). The effects of zeolite and ferrous sulphate in combination with the corona discharge were examined. Experiments were conducted for a range of process parameters including pH, conductivity, type and amount of zeolite, and ferrous sulphate concentration. A mathematical model to describe the kinetics of DO39 degradation in the corona reactor was developed. Aqueous phase pulsed streamer corona discharge as a method for coloured wastewater treatment showed very high effectiveness in the case of iron salt addition (Fenton's reaction). Low pH enhanced dye removal by corona in the absence of zeolite, thus implying that the acid properties of zeolites are important in dye degradation. Ecological parameters such as COD, TC, IC, TOC and IC50 measured before and after corona treatment showed that the treated wastewater can be discharged into the environment or reused as process water.

Adsorption-Coagulation for the Decolorisation of Textile Dye Solutions

Abstract Studies were undertaken for the removal of colour from different types of synthetic dye solutions by using powdered activated carbon (PAC) and bentonite clay (BC) as adsorbents. The different types of dyes (direct, mordant and basic) studied were Direct Orange, Eriochrome Black T and Malachite Green. The synthetic dye solutions behaved differently with the two adsorbents. The effect of adsorption by PAC and the further addition of a very small dose of a coagulant polyaluminium chloride (PAlC) on the settling and/or reuse of adsorbents used was studied. PAC and BC, though effective adsorbents, remained suspended in the solution for a long time. PAlC not only enhanced dye removal, but also formed a sludge that settled very quickly and which could also be reused effectively for dye removal.

Principles of colour loss. Part 2: Degradation of azo dyes by electron transfer, catalysis and radical routes

The objective of this study was to evaluate the potential for treating dye-contaminated waste streams by sorption using compost as a low-cost sorbent. A mature, thermophilic compost sample was used to sorb Cl Acid Black 24, Cl Acid Orange 74, Cl Basic Blue 9, Cl Basic Green 4, Cl Direct Blue 71, Cl Direct Orange 39, Cl Reactive Orange 16 and Cl Reactive Red 2 from solution using a batch-sorption method. With the exception of the two reactive dyes, the sorption kinetics were favourable for a continuous-flow treatment process with the compost-dye mixtures reaching a steady state within 3-5 h. Based on limited comparisons, the affinity of the compost for each dye appeared to be competitive with other non-activated carbon sorbents. The results suggest that additional research on using compost as a sorbent for dye-contaminated solutions is warranted.

Radiation chemistry of anionic disazo dyes in Cellophane films applications for high-dose dosimetry

Thin transparent Cellophane films containing anionic disazo “Direct” dyes, e.g. blue Cellophanes, have long been used as monitors of large absorbed doses of ionizing radiation (10–300 kGy) and especially for mapping electron-beam dose profiles. Examples of dyes for such purposes are variations on forms of the disazo dyes, Direct Orange, Direct Violet or Direct Blue. The films have a thickness of 25.6 μm (+0.1 μm) and are available in rolls of either 30 m×0.51 m or 60 m×0.76 m. Such dyed Cellophanes are typically lightfast but can readily be bleached irreversibly by ionizing radiation, as a means of dosimetry using spectrophotometry as the analytical tool. The radiation response is markedly dependent on temperature and relative humidity during irradiation. The reaction is initiated mainly by dehydrogenation and nitrosation upon electrophilic reductive attack on the dye molecule by the thermal electrons, at initial reaction rate constants in the range 10 5–10 6 s −1.

Electrochemical Determination of Some Organic Pollutants Using Wall‐Jet Electrode

AbstractDetermination of organic pollutants in trace level in a flow stream was developed using a wall‐jet electrode system and square‐wave stripping principles. Pesticides such as endosulfan, isoproturon and carbendazim, o‐chlorophenol and a benzidine bisazo dye, direct orange 8 were chosen for this study. The optimum conditions for adsorptive square‐wave stripping voltammetry were arrived at and the peak current responses of analyte were correlated over flow rate. Calibration plots were obtained by correlating the peak currents with concentration under optimum conditions. The best determination range, 1×10−4 to 4.0 mg/mL for endosulfan and 1×10−4 to 1.5 mg/mL for the remaining pollutants in a flowing stream was obtained with adsorptive square‐wave stripping technique.

A staining technique for evaluating the pore structure variations of microcrystalline cellulose powders

A staining technique was developed for evaluating the pore structure of microcrystalline cellulose powders. This technique used two direct dyes as molecular probes and was based on the differences between the two dyes' molecular size and affinity for microcrystalline cellulose. Direct Blue 1 has a smaller molecular size and weaker affinity for microcrystalline cellulose compared to Direct Orange 15, which has a larger molecular size and stronger affinity. We used the ratio of adsorbed Direct Orange 15 to adsorbed Direct Blue 1 after 48 h staining [designated as ( O B) 48 ] as the parameter for evaluating the pore structure variations between different microcrystalline cellulose powders. Seven microcrystalline cellulose samples of three different grades—Avicel PH-101, Avicel PH-102 and Avicel PH-103—were analyzed for their ( O B) 48 ratios, and significant differences were found. These differences are present primarily among different grades and seco among different batches of the same grade. Among the three grades tested, it was found the their ( O B) 48 ratios have the following sequence: Avicel PH-103 > Avicel PH-101 > Avicel PH-102. This suggested that structure variations are significant among different microcrystalline celluloses of both different grades and batches, but the degree of variation between different batches is less than that between different grades of microcrystalline cellulose.

Secretion of Ipa proteins by Shigella flexneri: inducer molecules and kinetics of activation.

The type III Mxi-Spa secretion machinery of Shigella flexneri is responsible for secretion of Ipa proteins, which are involved in the entry of bacteria into epithelial cells. Ipa proteins accumulate within bacteria growing in laboratory media, and their secretion is activated upon contact of bacteria with eukaryotic cells. In this study, we have identified a group of chemical compounds, including Congo red, Evans blue, and direct orange, which are able to induce secretion of Ipa proteins by bacteria suspended in phosphate-buffered saline. Parameters of kinetics of activation of Ipa secretion by Congo red were determined by measuring by enzyme-linked immunosorbent assay the amount of IpaC secreted and by investigating the increase in susceptibility of Ipa proteins to proteinase K degradation. Ipa secretion occurred at 37 degrees C, was obtained with 5 to 10 microM Congo red, and was complete within 30 min. In addition, activation of Ipa secretion by Congo red was observed with bacteria harvested throughout the exponential phase of growth but not with bacteria in the stationary phase. The interactions of Congo red and Congo red-related compounds with the Mxi-Spa secretion apparatus might be specific hydrophobic interactions similar to those involved in binding of Congo red to amyloid proteins.

Prevalence of contact allergy to non-disperse azo dyes for natural fibers: a study in 1814 consecutive patients.

5 non-disperse azo dyes, used for colouring natural fibers, were added to the standard patch test series, as 5% pet. preparations. 1814 consecutive patients attending the patch test clinic were patch tested, of whom 16 (0.88%) reacted to the newly added dyes: 8 to Direct Orange 34, 5 to Acid Yellow 61, 2 to Acid Red 359 and 1 to Acid Red 118. On the basis of clinical history and results of patch tests with pieces of fabrics, contact sensitization to non-disperse azo dyes seemed to be related to the appearance of skin lesions at least in 8 subjects. We conclude that systematic exploration of the sensitizing potential of textile dyes, selected after careful investigation, can provide additional information on the frequency of occurrence of textile dye dermatitis, supporting individual investigation in sensitized subjects.