Types Of Reactive Dyes Research Articles

Cu/Co Bimetallic Carbon Catalyst as a Highly Efficient Promoter for Reactive Dyes Degradation with PMS.

The synergistic effect between bimetallic catalysts has been confirmed as an effective method for activating persulfate (PMS). Therefore, we immobilized copper-cobalt on chitosan to prepare bimetallic carbon catalysts for PMS activation and degradation of reactive dyes. Experimental results demonstrate that the CuCo-CTs/PMS catalytic degradation system exhibits excellent degradation performance toward various types of reactive dyes (e.g., Ethyl violet, Chlortalidone, and Di chlorotriazine), with degradation rates reaching 90% within 30 min. CuCo-CTs exhibit high catalytic activity over a wide pH range of 3-11 at room temperature and under static conditions, degrading over 92% of RV5 within 60 min. ultraviolet-visible (UV-vis) spectroscopy and color changes in the dye solution confirm the effective degradation of RV5, with a degradation rate of 97.2% within 10 min. Additionally, CuCo-CTs demonstrate good stability and reusability, maintaining a degradation rate of 92.8% after eight cycles. Kinetic studies indicate that the degradation follows pseudo-first-order kinetics. Furthermore, based on the results of radical scavenging experiments, the catalytic degradation mechanism of the dye involves both radical and nonradical pathways, with 1O2 identified as the primary active species. This study provides insights and experimental evidence for the application of persulfate oxidation in the treatment of dyeing wastewater.

Identifying optimized conditions for developing dewatered alum sludge-based photocatalyst to immobilize a wide range of dye contamination

In the current investigation, the removal of Levafix Fast Red CA (LFR) and Levafix Amber CA (LA) azo-dyes from aqueous media using the Fenton/adsorption processes has been carried out. The water treatment by-product, namely alum sludge (AS), was successfully collected and calcined to various temperatures, i.e., 400, 600 and 800 °C, then tested for use as a catalyst in the Fenton/adsorption processes. Fourier transform infrared (FT-IR) transmittance spectrum analysis and Transmission electron microscopy techniques (TEM) were applied to investigate the structural and morphological properties of such a catalyst. The results displayed that the calcined AS at 400 °C (AS400) showed the best photocatalytic activity under ultraviolet illumination and sunlight irradiation. The results indicated that the adsorption/Fenton’s oxidation systems are efficient for treatment and eliminating such types of reactive dyes. The oxidation reaction using Fenton’s reagent reached 99.9 and 86% removal for LFR and LA dyes, respectively. The operating conditions revealed that the reaction was maximized at the operational parameters of 1 g/L and 800 mg/L for AS400 and H2O2 at acidic pH (3.0). The process of single dyes was studied either from thermodynamic and kinetic viewpoints and the data exhibited that the reaction is followed a pseudo-second- order kinetic model and an exothermic reaction nature. The practical application of such byproduct waste used as a photocatalyst source through using natural solar radiation introduces an industrial ecology approach in treating dye effluents for safer environment.

Effects of Metal Ions Present in Recycled Water on Washing of Reactive Dyed Cotton Fabric

Textile industry is a key source of contamination of heavy metal ions in water. These heavy metal ions include lead, cadmium, copper, arsenic, nickel, chromium, zinc, and mercury. These metals have been recognized as hazardous heavy metals because of their high degree of toxicity. Initially, copper was selected to determine the effects of metals present in recycled water during the washing process because of its extensive usage in the textile industry. However, copper becomes a part of process water while manufacturing and even a part of recycled water. Furthermore, recycled water contains such traces of metal that can cause problems during its reuse. In the current research, the presence of copper ions in water was simulated with copper sulphate and the obtained water was used for washing of fabric after reactive dyeing. The effects of salt on washing of three different types of reactive dyes, that is, monochlrotriazine, dichlorotriazine and vinylsulphone were evaluated by washing of dyed fabric. Moreover, evaluation process was achieved with different concentrations of salt at different temperatures, pH values, and time intervals. Besides, K/S, fixation%, color uniformity, color change, washing fastness, and rubbing fastness of samples were measured during evaluation. Results were also compared with detergent and water wash. Eventually, the results showed that copper has a prominent effect on fabric. Hence, it would be possible to allow certain concentrations of copper during the process of washing.
 Index Terms: cotton, exhaust dyeing, metal ions, reactive dye, recycled water

Assessing the Effectiveness and Environmental Sustainability of Reactive Dyes for Their Structural Diversity

This study aims to assess the environmental impact of different chemical classes of reactive dyes and their treatment. To attain this outcome, four different types of reactive dyes (Procion Blue PX-3R (Monochlorotriazine), Levafix Blue CA (Bi-functional heterogeneous), Remazol Brilliant Blue R (Vinylsulphone) and Remazol Brilliant Blue RR (Bi-functional homogeneous) on the cotton fabric were analyzed. The potential cytotoxic effect of different reactive dyes was evaluated using the growth inhibition test according to AATCC 22662 by exposing the culture over 72 hours at 21 °C. The dyeing operation was performed in a labrotex sample dyeing machine, and a data color spectrophotometer was administered to analyze the strength percentage of dyes in post-dye liquor. Among the reactive dyes, Levafix Blue CA exhibited better effluent characteristics compared to others, lowering the threat to the environment. The dyed wastewater was directly disposed of and treated in a pilot plant containing lime and ferrous sulfate as coagulant and polyacrylamide as polyelectrolyte, which resulted in a significant reduction of BOD5 (64.97-74.67%), COD (61.03-70.28%), TDS (55.02-61.97%) and TSS (47.07-50.19%) with improved pH and DO values. This investigation reflects the specific selection of a reactive dye leading to a lower environmental impact of a dyeing process coupled with wastewater treatment processes.

Wet processing of agro-residual fibres for potential application in fancy décor items

ABSTRACT This research compares the change of physical and chemical properties of three types of agro-residual (AgR) fibres namely banana plant stem fibre (BSF), pineapple leaf fibre (PALF) and corn husk fibre (CHF) by wet processing steps: scouring, bleaching and dyeing. Bleaching operation was performed using mild sodium chlorite concentration. The percentage of lignin and hemicelluloses were remarkably declined and densities of the fibres were increased. The highest amount of α-cellulose is found 88.7% for bleached BSF, followed by bleached PALF (78.4%) and bleached CHF (70.1%). The morphology changes of the fibres due to bleaching were clearly detected by FTIR spectroscopy. The bleached fibres were dyed with two different types of reactive dyes viz. Reactive Orange 2 R-XF and Reactive Blue F-R by conventional dyeing technique. The absorption of dyes was tested by UV-vis spectroscopy. It was seen that the dye absorption percentage of all types of fibre are not equal. The dye absorption was also diverged in the case of two reactive dyes. Colour fastness properties of dyed fibres were tested under sunlight, wash and reagent spot tests. All the dyed fibres were exhibited excellent colour fastness properties. Reactive Orange 2 R-XF showed better fastness property than Reactive Blue F-R in every investigation.

Comparative Study on Dyeing of Cotton, Modal and Lyocell Fabrics Using Bifunctional and Polyfunctional Reactive Dyes

Polyfunctional reactive dyes have been introduced by the renowned dye manufacturers in the recent years for better exhaustion and fixation performance. This paper deals with evaluation of the dyeing performance of three cellulosic fibres namely cotton, modal and lyocell with polyfunctional (Avitera Cardinal SE) reactive dye in comparison a bifunctional-(Novacron Brilliant Red FN-3GL) reactive dye. The purpose of this study is to achieve a better understanding of exhaustion and fixation behaviour in dyeing of cotton, modal and lyocell fibres using these two types of reactive dyes. The dyeing was carried out at four different shade% (1%, 2%, 3%, and 4%). Besides studying exhaustion (%) and fixation (%) along with K/S values of dyed fabrics, several other quality parameters e.g. bursting strength, pilling resistance and colour fastness to wash were also examined. Finally, the optimum combination among the three types of cellulosic fabrics and two types of reactive dyes was observed. Lyocell fabric and polyfunctional reactive dyes have been found more sustainable.

Brine Recycling from Industrial Textile Wastewater Treated by Ozone. By-Products Accumulation. Part 2: Scaling-Up

Extremely high volumes of salty wastewater are produced by textile manufacturers daily. Therefore, brine recycling from the wastewater should be regarded as a crucial issue within the textile industry. Ozonation was used in this two-part study as a purification method for industrial textile wastewater polluted by low-molecular-weight salts (LMWS). Part 1 revealed the accumulation of ozonation by-products in a multi-recycling system. The objective of Part 2 was the scaling-up of the process and the investigation of the occurrence of by-products. It was found that ozonation works well in an alkaline reaction medium, which was characteristic of the wastewater from a dye house; an almost complete color removal was achieved within 30 min of treatment. The brine that was produced from the wastewater treated by ozonation in a 20 L bubble column reactor was recycled successfully. Dyeing of cotton with five types of reactive dyes in various shades resulted in very good values of DECMC, which is the normative color matching parameter, and were between 0.15 and 1.2. The color fastness obtained for upcycled fabrics were satisfactory, and not worse than standard values. Although accumulation of the side products was detected in Part 1, the fabric discharges produced in the scaled-up process were free from carcinogenic amines and heavy metals. The study indicated that ozonation can be applied in the industry as a method for textile wastewater recycling.

Reactive dyeing of ramie yarn washed by liquid ammonia

The washing efficiency of water, nonionic soap solution, reflux solution, pure liquid ammonia (99.99%), and solvated liquid ammonia was studied on dyed ramie yarns. The ramie yarn samples were dyed with a 2% on weight of fiber (o.w.f) shade with five types of reactive dye by the classical exhaustion method. The washing performances of these solvents were quantified by the dye removal rate, the color uniformity, and the color fastness properties (washing, rubbing, and lightness). Furthermore, the influence of these wash methods on the physical properties of the final yarn samples including shrinkage, tensile strength, and elongation was schematically examined. The results of these measurements revealed that the dye removal rates during the washing in pure liquid ammonia and solvated liquid ammonia were lower than the yarn washed in water, soap solutions, or reflux solutions. The color uniformity (expressed as the standard deviation of K/S values for all dyed ramie yarns) was within the acceptable limits with the satisfactory color fastness levels. The shrinkage values of yarns that were washed in the pure liquid ammonia and the solvated liquid ammonia were both similar (9.0%) and considerably higher than the samples washed in water (1.8%), soap solution (2.4%), or reflux solution (2.6%). The tensile strength and the elongation of the resultant yarns improved significantly when the samples washed in pure liquid ammonia. The yarns that were washed in the solvated liquid ammonia solutions had decreased tensile strength and elongation. The cause of the decrease was determined by the XRD measurements, which confirmed that the crystallinity, and the orientation of these fibers decreased dramatically after being washed in the ammonia system solutions. The samples that were washed in the liquid ammonia had a smoother surface morphology than the other washing processes.

Effects of Water Hardness on Dyeing of Cotton Fabrics with Different Types of Reactive Dyes and Shade Percentages

This research was investigated the influence of water hardness on dyeing of cotton fabric with three types of reactive dyes (Synozol, Ramazol and Setazol). The effects of various fastness (color fastness to wash, abrasion test, Rubbing test and Perspiration test) properties of dyes were also studied and reported in this paper in details. Single color (Blue) is used for the shade of 1% and 2% and varied water hardness of 120 ppm, 70 ppm and 9 ppm respectively. The main objective of this paper was to find out the parameters of various fastness properties at different range of water hardness in the application of different types of reactive dyes. It is visualized that different amount of water hardness showed in different fastness for using three types of reactive dyes having shade of 1% and 2%. We reported that water hardness up to 9 ppm, for using three types of reactive dyes showed excellent wash fastness and it deteriorates with increasing hardness. Setazol 1% & 2%, showed highest abrasion resistance at 9 ppm water hardness compare to other dyes at higher water hardness. Rubbing test result also showed very good for 9 ppm water hardness in three reactive dyes irrespective of shade percentage. The perspiration test result is good at 9 ppm water hardness for all types of reactive dyes with all shade percentages.

Simultaneous dyeing and functional finishing of cotton fabric using reactive dyes doped with TiO2 nano-sol

A new approach for simultaneous salt-free dyeing and functional finishing, i.e. UV protection and antibacterial properties of cotton fabric were studied. In this study, cotton fabric was cationized with 3-chloro-2-hydroxypropyl trimethylammonium chloride. Two types of reactive dyes (CI Reactive red 120 and CI Reactive yellow 145) were doped with different amounts (0.035, 0.053, and 0.07 mol) of TiO2 nano-sol by sol–gel method and applied on cationized cotton fabric using pad–dry–steam method without the addition of salt. The chemical and morphological structures of the dyed fabrics were characterized by attenuated total reflection-Fourier transform infrared, scanning electron microscopy, transmission electron microscopy, and X-ray diffractometry. Different properties were investigated such as color strength, fixation, fastness properties (washing, rubbing, and light), UV blocking, antibacterial activity, and tensile strength. Samples dyed with titanium dyeing solutions exhibited better antibacterial efficacy and durable UV protection, with minimal impact on color depth and tensile strength compared with the samples dyed with commercial reactive dyes.

A novel printing method to enhance the fixation of reactive dyes on wool–polyamide fabrics

The aim of this paper is to explain how colour fastness results are improved as a result of increasing the degree of fixation of reactive dyes on wool, polyamide and wool–polyamide blend fabrics. Wool–polyamide blend fabrics were printed with two different types of reactive dyes, e.g. monochlorotriazine and vinylsulphone. Trichloroacetic acid (TCAA) was added to the printing paste for controlling the pH level during the fixation process to get a maximum colour yield and a maximum dye fixation on the two components of the blend, e.g. wool and polyamide. In order to accelerate the reaction rate, a quaternising agent, e.g. triethylamine (TEA) was also added to the printing paste. The factors that may affect the efficiency of printing method, e.g. the concentration of TCAA, urea, wetting agent, TEA, steaming time and temperature were studied in detail.

Dyeing Properties to Soybean/Flax Blended Yarn with Reactive Dyes

For producing more colorful soybean /flax blended yarns and fabrics and to evaluate the dye-ability of the blends yarn, two types of reactive dyes, containing mono- and bi-functional reactive groups, were studied. On basis of a number of experiments, influences of time and temperature, alkali dosage, addition of promoter are analyzed, the optimum conditions to soybean/flax fibers with Reactive Yellow K-R and Reactive Yellow B-4RFN are defined. Results of performance test indicate that both K-type reactive dyes and B-type reactive dyes have good colorfastness and levels, especially for light to moderate color, and B-types is better than K-types. The colorfastness of the dyed yarns can meet the general requirements.

Possibilities of polymer‐aided dyeing of cotton fabric with reactive dyes at neutral pH

AbstractWater‐soluble polymers have versatile application, viz., water‐soluble polyacrylates have been widely used in the reactive dyeing of cellulosic fibers and the related soaping as an important component of the leveling and washing agent. In this article, one such water‐soluble polymer, polyacrylic acid has been synthesized, characterized, and applied in conjunction with various types of reactive dyes, namely triazinyl, vinyl sulfone, high exhaustion, and bifunctional reactive dyes, along with crosslinking agents, namely glycerol 1,3‐dichlorohydrin and hexamethylene tetramine‐hydroquinone, respectively. One of the crosslinking agents (the former one) has been synthesized in the laboratory. Crosslinking agent is necessary to adhere the dye molecule onto the cellulose macromolecule. Different process sequences have been formulated and explored for dyeing purpose. All such dyeings were carried out at neutral pH. The dyed samples were assessed through color strength in terms of K/S values and their fastness properties were assessed by standard methods. All such dyeings were compared with conventional dyed samples. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Decolorization and Mineralization of Reactive Dye by UV/Fenton Process

The photochemical degradation of C. I. Reactive Blue 2 (RB2) in aqueous solution has been studied using a homogeneous UV/Fenton process. The effects of applied H2O2, Fe2+ salt and RB2 concentrations at constant UV irradiation characteristics, the pH, and temperature were determined. By the application of 0.5 mM Fe2+ and 2.5 mM of H2O2 the complete color removal and mineralization extent of 73.8% were achieved. According to the color and TOC removal, it could be suggested that the studied UV/Fenton type process appeared as a viable technique for the treatment of wastewater containing such types of reactive dyes.

Oxidation of Levafix CA reactive azo-dyes in industrial wastewater of textile dyeing by electro-generated Fenton's reagent

The indirect electrochemical removal of pollutants from effluents has become an attractive method in recent years. Removal (decolorization and mineralization) of Levafix Blue CA and Levafix Red CA reactive azo-dyes from aqueous media by electro-generated Fenton's reagent (Fe(2+)/H(2)O(2)) using a reticulated vitreous carbon cathode and a platinum gauze anode was optimized. Progress of oxidation (decolorization and mineralization) of the investigated azo-dyes with time of electro-Fenton's reaction was monitored by UV-visible absorbance measurements, Chemical oxygen demand (COD) removal and HPLC analysis. The results indicated that the electro-Fenton's oxidation system is efficient for treatment of such types of reactive dyes. Oxidation of each of the investigated azo-dyes by electro-generated Fenton's reagent up to complete decolorization and approximately 90-95% mineralization was achieved. Moreover, the optimized electro-Fenton's oxidation was successfully applied for complete decolorization and approximately 85-90% mineralization of both azo-dyes in real industrial wastewater samples collected from textile dyeing house at El-Mahalla El-Kobra, Egypt.

Application of membrane processes in closing of water cycle in a textile dye-house

In this study, investigations were made to close water cycle in dye-houses. At the first stage, optimum operation conditions of a membrane nanofiltration were determined. Experiments were carried out for DL membranes (Osmonics, USA). The effect of temperature, pressure and pH was investigated. Investigations were performed for different types of real wastewater produced in a laboratory-scale Pyrotec S dyeing apparatus (Roaches) for various types of reactive dyes. An over 90% dye hold-up was obtained for all dye baths. At the final stage of the experiments, dyeing processes were carried out with the use of a filtrate from nanofiltration as water applied for dyeing, rinsing and washing after dyeing. In cooperation with the Technical University of Lodz, we have managed to apply biological degradation of the concentrate, carried out in two different reactor systems.

Dyeing behaviour of lyocell fabric: effect of NaOH pre-treatment

To understand the effect of alkali pre-treatment on the dyeing of lyocell fabrics, samples are pre-treated with 0.0–7.0 mol dm−3 NaOH using a pad-batch process and then dyed with different types of reactive dyes. Exhaustion, fixation, and visual colour strength (K/S values) are measured. It is observed that sodium hydroxide pre-treatment significantly improves the colour yield, exhaustion, and fixation for all dyes used. Highest K/S values are obtained when the fabrics are pre-treated with 2.0–2.5 mol dm−3 NaOH. Cross-sectional analysis shows that below this optimum concentration the core fibres in the yarn are not dyed; at optimum concentration all fibres in yarn cross-section are homogeneously dyed. Cross-sectional analysis shows that as the pre-treatment concentration of NaOH increases above 2.5 mol dm−3, the fibres change progressively from a circular to angular cross-section, forming a solid unit. The decrease in K/S above the treatment concentration of 2.5 mol dm−3, though the %E and %F remains almost constant, is attributed to the distribution of dye over a larger surface area of the outer fibres in the yarn cross section, forcing the K/S at λmax to decrease.

Identification of Newer Types of Reactive Dyes on Cellulosic Fibres - IV

The reactive systems and chromogens present in further types of reactive dyes are briefly discussed. The results are described of tests on dyeings (or prints) of selected reactive dyes on cotton, carried out to distinguish between the various chemical classes and to place them in their apparent position in Clayton's Tables. Particular attention is paid to the black reactive dyes, and a scheme is proposed for differentiating between dyeings of 25 different black reactive dyes on cotton.

Dyeing behaviour of lyocell fabric: effect of fibrillation

To understand the effect of fibrillation in dyeing, non‐fibrillated lyocell fabrics and fibrillated lyocell fabrics were dyed with different types of reactive dyes. Their exhaustion, fixation and K/S values were measured and compared. It was observed that fibrillated lyocell shows lower visual colour yield than non‐fibrillated lyocell, independent of the exhaustion and fixation. It was also observed that some bifunctional reactive dyes, because of the location of reactive groups and flexibility of their structure, reduced fibrillation of lyocell through crosslinking. It was shown that defibrillating fibrillated lyocell with a cellulase enzyme increased the visual colour yield. Non‐fibrillated lyocell fabrics after dyeing were subjected to a hydroentanglement treatment to create a fibrillation effect. These properties suggest that the lower visual colour yield of fibrillated lyocell is not mainly attributed to any change in fibre properties of the fibrils, but as a result of the light scattering from the fibrillated fabric surface.

Decolorization of textile plant effluent by Citrobacter sp. strain KCTC 18061P

Citrobacter sp. strain KCTC 18061P was found to be able to decolorize textile plant effluent containing different types of reactive dyes. Effects of physico-chemical parameters, such as aeration, nitrogen source, glucose and effluent concentrations on the color removal of real dye effluent by this strain were investigated. The observed changes in the visible spectra indicated color removal by the absorption of dye to cells during incubation with the strain. This strain showed higher decolorization ability under aerobic than static culture conditions. With 1% glucose, this strain removed 70% of effluent color within 5 days. Decolorization was not significantly dependent on the nitrogen sources tested. Chemical oxygen demand (COD) and biological oxygen demand (BOD) were decreased in proportion to incubation times, and their removal rates were about 35% and 50%, respectively, at 7 days of culture.