Cotton Dyeing Process Research Articles

PH-Mediated Antibacterial Dyeing of Cotton with Prodigiosins Nanomicelles Produced by Microbial Fermentation.

This study developed a novel pH-mediated antimicrobial dyeing process of cotton with prodigiosins nanomicelles produced by microbial fermentation. The average diameter of the pigment nanomicelles was 223.8 nm (range of 92.4–510.2 nm), and the pigment concentration was 76.46 mg/L. It was found that the superior dyeing effect of cotton fabric was achieved by adjusting the dye bath pH. When the pH was three, dyed cotton under 90 °C for 60 min exhibited the greatest color strength with good rubbing, washing and perspiration color fastness. By the breaking strength test and XRD analysis, it was concluded that the cotton dyed under the optimum condition almost suffered no damage. In addition, due to the presence of prodigiosins, dyed cotton fabric under the optimal process showed outstanding bacteriostatic rates of 99.2% and 85.5% against Staphylococcus aureus and Escherichia coli, respectively. This research provided an eco-friendly and widely-applicable approach for antimicrobial intracellular pigments with the property of pH-sensitive solubility in water to endow cellulose fabric with color and antibacterial activity.

Reuse of dye-colored water post-treated with industrial waste: Its adsorption kinetics and evaluation of method efficiency in cotton fabric dyeing

In this study, the potential for the use of an industrial waste (IW) as an adsorbent for the treatment of aqueous solutions containing C.I. Direct Black 22 was investigated. A kinetic study was performed to investigate the best conditions for adsorption, evaluating the effect of temperature and the adsorbent mass on the thermodynamics of the adsorption processes. Under the best conditions, 95.7% efficiency was achieved within 24h. Pseudo-second-order kinetics models were applied to the experimental data and the correlation coefficients (r2) were higher than 0.98. The treated water was successfully reused in a cotton dyeing process. The best results were obtained with thermally-treated industrial waste, where lower color difference (ΔE) values were observed (0.32–0.70) for dye concentrations of 0.5, 1.0 and 1.5% (w/w). In the case of the raw industrial waste, ΔE values of 0.54 (1.5%, w/w, dye) and 1.36 (2.0%, w/w, dye) were obtained.

Determination of the Dyeing Potential of Mint and Sage Crops Wastes on Wool and Cotton Fibers

ABSTRACTIn the present study, dyeing potential of waste water from distillation process was investigated for fresh and dried herbs of Menthaspicata (MS), Menthapiperita (MP), and Salvia officinalis (SO) species. Meta-mordanting method was used in the dyeing of wool and cotton fabrics in the presence of FeSO4·7H2O (iron) and AlK(SO4)2·12H2O (alum) mordants. The color of each dyed material was investigated in terms of the CIELab (L*, a*, b*, C, and h°) and K/S values. The surfaces of the samples were observed using a scanning electron microscope. It was observed that the color strength of fresh and dried plant is depended on the plant species, mordant, and fabric type. Best color intensity (K/S = 16.68) was obtained with iron mordant using fresh SO on cotton fabric. For wool fabric, the highest color strength (K/S = 9.62) was obtained with fresh SO in the presence of alum mordant. Presence of metal mordant for natural dyeing process of cotton with MS, MP, and SO extract has shown remarkable improvement in terms of dye adherence and fastness properties thus metal mordanting could be suitable alternative dyeing method for ecofriendly industrial application.

A novel approach for a natural dyeing process of cotton fabric with Hibiscus mutabilis (Gulzuba): process development and optimization using statistical analysis

Abstract Since early times, dyes derived from natural sources have emerged as an important alternative to synthetic dyes. Therefore, there is a need to develop new techniques of leaching natural colorants from plant materials for dyeing applications. The present paper investigates an eco-friendly dyeing process of cotton with the aqueous extract of Hibiscus mutabilis (Gulzuba) without metal salts. During this process, the dyeing step was carried out on modified cotton by several cationizing agents in order to improve its dyeability. Cationized cotton fibres were characterized by Fourier transform infrared (FTIR) spectra and the scanning electron microscope (SEM) images. The effect of the main operating conditions (pH of the dye bath, temperature, dyeing duration, cationizing agent nature and concentration) on the dyeing quality resulted has been studied. Then, the optimization of the dyeing process was released using a response surface methodology. The performances of this dyeing process were evaluated by measuring the colour yield (K/S) of the modified cotton. It was found that cationizing cotton improves the dyeing quality and the fastness properties.

Green Process for Indigo Dyeing: Effect and Modeling of Physico-chemical Parameters Using Statistical Analysis

Textile Industries use different chemicals in indigo dyeing processes. Interest in eco-friendly processing in the textile industry has recently increased because of a larger awareness of environmental issues. For the case of indigo dyeing process, the reducing agent conventionally used is the - environmentally unfavourable - sodium dithionite, which will be replaced in this study with an ecological reducing agent called acetol that is also known as hydroxyacetone. In this paper, measurements of the redox potential at various experimental conditions were carried out in a dyeing bath, where acetol is the reducing agent of indigo. Moreover, an unconventional but eco-friendly indigo dyeing process of cotton was investigated. The effects of: reduction duration, dyeing duration, reduction temperature, alkalinity and the amount of indigo on the performances of this dyeing process were studied, and the dyeing results were evaluated by measuring the colour yield parameter (K/S) of the dyed samples at 660 nm. Finally, a factorial design was employed for the experimental plan; mathematical model equation and statistical analysis were derived by computer simulation applying the least squares method using Minitab 15.

A promising route to dye cotton by indigo with an ecological exhaustion process: A dyeing process optimization based on a response surface methodology

The present paper investigates a non conventional but eco-friendly exhaust dyeing process of cotton with indigo. During this process, indigo was converted to its water-soluble leuco form by a green reducing agent: the glucose, in presence of alkali and at high temperature.To improve the exhaust dyeing process, the dyeing step was carried out on modified cotton by several cationizing agents. Modified cotton fibres were characterized by Fourier transform infrared (FTIR) spectra and an X-ray diffraction analysis. The performances of the dyeing process were evaluated by measuring the bath exhaustion E (%), the colour yield (K/S), the brightness index BI (%) and the dyeing fastnesses of the coloured cotton. It was found that the colour yield and the brightness obtained from the exhaustion dyeing were improved when using cationized cotton giving fastness properties better than those obtained with untreated cotton dyed by the conventional process. The effect of the main operating conditions (cationizing agent nature and concentration, reducing temperature, dyeing duration, dyeing temperature) on the quality of this dyeing process were also studied. A surface design was employed for experimental design and optimization of results. Mathematical model equation and statistical analysis were derived by computer simulation programming applying the least squares method using Minitab 15.

Indirect Electrochemical Reduction and Cotton Dyeing Process in Fe(Ⅲ)-Oxalate-Calcium Gluconate System

Indirect Electrochemical Reduction and Cotton Dyeing Process in Fe(Ⅲ)-Oxalate-Calcium Gluconate System

Treatment of wastewater from a cotton dyeing process with UV/H2O2 using a photoreactor covered with reflective material

Wastewater containing several dyes, including sulfur black from the dyeing process in a textile mill, was treated using a UV/H2O2 process. The wastewater was characterized by a low BOD/COD ratio, intense color and high acute toxicity to the algae species Pseudokirchneriella subcaptata. The influence of the pH and H2O2 concentration on the treatment process was evaluated by a full factorial design 22 with three replicates of the central experiment. The removal of aromatic compounds and color was improved by an increase in the H2O2 concentration and a decrease in pH. The best results were obtained at pH 5.0 and 6 g L(-1). With these conditions and 120 min of UV irradiation, the removal of the color, aromatic compounds and COD were 74.1, 55.1 and 44.8%, respectively. Under the same conditions, but using a photoreactor covered with aluminum foil, the removal of the color, aromatic compounds and COD were 92.0, 77.6 and 59.4%, respectively. Moreover, the use of aluminum foil reduced the cost of the treatment by 40.8%. These results suggest the potential application of reflective materials as a photoreactor accessory to reduce electric energy consumption during the UV/H2O2 process.

Treatment of a Textile Effluent from Dyeing with Cochineal Extracts UsingTrametes versicolorFungus

Trametes versicolor (Tv) fungus can degrade synthetic dyes that contain azo groups, anthraquinone, triphenylmethane polymers, and heterocyclic groups. However, no references have been found related to the degradation of natural dyes, such as the carminic acid that is contained in the cochineal extract. Experiments to determine the decolorization of the effluent used in the cotton dyeing process with cochineal extract by means of Tv fungus were done. Treatments to determine decolorization in the presence or absence of Kirk's medium, glucose, and fungus, with an addition of 50% (v v-1) of nonsterilized effluent were performed. Physicochemical characterization was performed at the start and end of the treatment. Degradation kinetics were determined. A direct relationship was found between the dry weight of fungi, pH, and the decolorization system, with higher decolorization at lower pH levels (pH ~4.3). High decolorization (81% ± 0.09; 88% ± 0.17; and 99% ± 0.04) for three of the eight treatments (Kirk's medium without glucose, Kirk's medium with glucose, and without medium with glucose, respectively) was found. Toxicity tests determined an increase in the initial effluent toxicity (7.33 TU) compared with the final treatment (47.73 TU) in a period of 11 days. For this system, a degradation sequence of the carminic acid structure present in the effluent by the Tv fungus is suggested, in which it is seen that metabolites still containing aromatic structures are generated.

Electrochemical-assisted photodegradation of mixed dye and textile effluents using TiO 2 thin films

Mixed dye consists of six commercial dyes and textile effluents from cotton dyeing process were treated by electrochemical-assisted photodegradation under halogen lamp illumination. Two types of effluents were collected which are samples before and after undergone pre-treatment at the factory wastewater treatment plant. The photodegradation process was studied by evaluating the changes in concentration employing UV–vis spectrophotometer (UV–vis) and total organic carbon (TOC) analysis. The photoelectrochemical degradation of mixed dye was found to follow the Langmuir Hinshelwood pseudo-first order kinetic while pseudo-second order kinetic model for effluents by using TOC analyses. The chemical oxygen demand (COD) and biochemical oxygen demand (BOD) values of mixed dye and raw effluents were reported. Photoelectrochemical characteristic of pollutants was studied using the cyclic voltammetry technique. Raw effluent was found to exhibit stronger reduction behaviour at cathodic bias potential but slightly less photoresponse at anodic bias than mixed dye.

Excellent dye fixation on cotton dyed in supercritical carbon dioxide using fluorotriazine reactive dyes

Development of a water-free dyeing process for cotton is essential for the textile industry due to ecological and economical reasons. In this study, a dyeing method is described where cotton has been effectively dyed in supercritical carbon dioxide (scCO2). Excellent dye fixation of 100%, and colour strength (K/S) values up to 30, were achieved in a small batch reactor and in a scale-up vessel. A series of non-polar reactive dyes with fluorotriazine as reactive group were synthesised at our laboratory. Fluorotriazines were found to be the best dyes for dyeing cotton and their reaction with cotton was improved by adding small quantities of acids to the reaction medium. H3PO4 and HAc were tested at different concentrations on cotton dyed with fluorotriazines. Evenly dyed pieces of cotton without any damage to the cotton fibres were observed in all experiments. An important step forward has been made for the future commercialization of a green process for industrially dying cotton in scCO2. Elimination of water and its costly treatment can be now achieved in the cotton dyeing process.