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Copyright of Journal of Engineering & Sustainable Development is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• Crosslinking-induced precipitation for PVA and reactive dyes removal was proposed. • The salts, alkali, and temperature are the crucial factors in precipitation. • MgSO 4 was used as coagulant to facilitate the removal of the residual color. • PVA polymers can promote the dye coagulation by MgSO 4. • 88%, 86%, and 99% of COD, PVA, and color were removed by the two-step process. High chemical oxygen demand (COD) and a strong color, which primarily originates from desizing and dyeing operations, are two major removal objectives in textile wastewater treatment. In this study, crosslinking-induced precipitation via the covalent bonding between –OH groups of PVA and vinyl sulfone groups of reactive dyes is proposed to simultaneously remove poly(vinyl alcohol) (PVA) and reactive dyes. Due to the nucleophilic addition reaction under an alkaline condition, PVA polymers can be efficiently crosslinked by dye molecules and destabilized in the presence of alkali and Na 2 SO 4. Additionally, due to the high coagulation efficiency under the alkaline conditions, MgSO 4 was used as a coagulant to facilitate the removal of the residual color after precipitation. After a two-step process, whereby coagulation was followed by crosslinking-induced precipitation, the maximum efficiencies of the removal of COD, PVA, and color attained 88.9%, 86.3%, and 99.2%, respectively, when the PVA monomer/RB5 mole ratio was 400. We hope that this technically feasible, highly efficient, and cost-effective process provides a basis for the practical application of the simultaneous treatment of desizing and dyeing wastewater. [ABSTRACT FROM AUTHOR]

In this study, a practical approach that provided a value-added to Turkey was aimed for the treatment of textile effluents. In this context, hazelnut shell (HS), as a harmless waste and without an alternative usage, was utilized in treatment of synthetically prepared wastewaters in laboratory given the position of Turkey in the world in terms of hazelnut produciton. FTIR, SEM-EDS, and XRD analyses showed organic bond structure, morphological and elementel propoerties of HS. Subsequently, removal of various reactive model dyes was investigated under different operating conditions such as initial pH, initial Reactive dye concentration, adsorbent concentration, reaction time, and temperature. Kinetic analyses showed that adsorption process was controlled by both pseudo second order and intra particuler diffusion models. Equilibrium studies showed that Langmuir isotherm stated the process better. Thermedynamic parameters showed that the process was endothermic, spontaneous, and had an affinity that increased by increasing temperature. [ABSTRACT FROM AUTHOR]

Ozonation of chloride-rich textile wastewater is a common pretreatment practice in order to increase biodegradability and therefore meet the discharge limits. This study is the first to investigate ozone-chloride/bromide interactions and formation of hazardous adsorbable organic halogens (AOX) in real textile wastewater. Initially effect of ozonation on chloride-rich real textile wastewater samples were investigated for adsorbable organic halogens (AOX) formation, biodegradability and toxicity. After 15 min of ozonation, maximum levels of chlorine/bromine generation (0.3 mg/l) and AOX formation (399 mg/l) were reached. OUR and SOUR levels both increased by approximately 58%. Daphnia magna toxicity peaked at 100% for 10 min ozonated sample. Considering adverse effects of ozonation on chloride-rich textile industry effluents, we proposed replacement of NaCl with Na 2 SO 4. Comparative ozonation experiments were carried out for both chloride and sulfate containing synthetic dyeing wastewater samples. Results showed that use of sulfate in reactive dyeing increased biodegradability and decreased acute toxicity. Although sulfate is preferred over chloride for more effective dyeing performance, the switch has been hampered due to sodium sulfate's higher unit cost. However, consideration of indirect costs such as contributions to biodegradability, toxicity, water and salt recovery shall facilitate textile industry's switch from chloride to sulfate. Image 1 • Use of sulfate in reactive dyeing increased biodegradability and decreased acute toxicity. • Although use of sulfate has a high cost, also subjects such as biodegradability, low toxicity, water and salt recovery have advantages. • Ozonation is as an auxiliary process that increased biological degradability, it also caused increased toxicity for textile wastewaters. [ABSTRACT FROM AUTHOR]

In the present investigation, date seed-derived biochar was applied as economic and effective sorbent for remediation of reactive dye from contaminated solutions. Biochar produced at 350°C through pyrolysis process exhibited reactive black 5 (REB5) sorption capacity 2.7 times higher than virgin date seeds. The surface of biochar was analyzed through Fourier transform infrared and scanning electron microscope data. The maximum REB5 uptake determined through the Langmuir model was found to be 113.4 mg/g. The REB5 sorption kinetics were accurately described by the pseudo-first-order model than pseudo-second-order model. Thermodynamic parameters indicated that REB5 sorption was spontaneous, feasible, and endothermic process. [ABSTRACT FROM AUTHOR]

A real anhydrous liquid ammonia dyeing technique was established that included a cationic modification of the ramie fiber in liquid ammonia, dyeing of the cationic ramie fiber in liquid ammonia, drying to fix the cationic agents and the reactive dyes in the ramie fiber, and washing the cationic ramie fiber and the dyed cationic ramie fiber with liquid ammonia to remove the unfixed chemicals. The zeta potential of the cationic ramie fiber indicated that the cationic groups were successfully grafted on the fiber. The dye exhaustion percentage and the fixation rate improved. The dyed cationic ramie fiber had excellent wash fastness, satisfactory color uniformity, and acceptable breaking strength and breaking elongation rate for spinning. High performance liquid chromatography analysis was used to measure the stability of the dye's reactive group during the liquid ammonia dyeing and drying. The results showed that the dichlorotriazinyl group was unstable, while the monochlorotriazinyl and vinyl sulfone groups were stable during the liquid ammonia dyeing. The monochlorotriazinyl group and vinyl sulfone groups changed to their non reactive derivatives after drying. [ABSTRACT FROM AUTHOR]

Copyright of Mycosystema is the property of Mycosystema Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reactive dyestuff is commonly used in the textile industry. Reactive dyebath wastewater (RDW) was treated with a batch, monopolar, parallel lab scale electrocoagulation process (EC) having 0.042 m2 effective electrode area. The effects of process parameters, such as initial pH, current density and electrolysis period on COD and color removal efficiency, were investigated by using response surface methodology (RSM). At the optimal conditions, 85.8% color and 76.9% COD removal were obtained with 1.84 €/m3 operating cost for Al electrode, while 92.0% decolorization and 80.9% COD removal were obtained with 1.56 €/m3 operating cost for an iron electrode. The iron electrode was found superior to aluminum as a sacrificial anode material in terms of COD and color removal with low cost. The cost of electrical energy, electrode, and chemical consumptions for electrocoagulation were considered to find an optimum and feasible solution. As a result, the operating cost consists of approximately 2% for energy, 28% for electrode and 70% for chemical consumption for both electrodes. Based upon the data, it is clearly seen that operating cost covers mostly for HCI to adjust pH due to the high pH and alkalinity of RDW, which was neglected in many studies. The first-order reaction kinetics with a higher slope for the color were well fitted, resulting in faster color removal than that of COD for both electrodes. [ABSTRACT FROM AUTHOR]

The morphology and structural defects of nanocrystalline photocatalysts (NCPHCs) play a pivotal role in their catalytic features. Herein, various morphologies of nickel molybdate (NiMoO 4) NCPHCs were synthesized via a hydrothermal route in the presence of various shape controllers (SCs) followed by a calcination process. The SCs including β-cyclodextrin (β-CD), Tween 20, ethylenediaminetetraacetic acid, and sodium dodecyl sulfate led to the formation of the rod, urchin, sphere, and flake-like morphologies of NiMoO 4, respectively. X-ray diffraction, Raman, X-ray photoelectron spectroscopy, and Fourier-transform infrared spectroscopy results corroborated a pure phase of monoclinic crystal structure of NiMoO 4 by utilizing the SCs in the reaction medium, whereas the SC-free NiMoO 4 demonstrated the mixed α- and β-phases. To investigate the effect of morphology on the photocatalytic activity of NiMoO 4 NCPHCs, the photocatalytic decolorization of Everzol Yellow 4GL, a bio-resistant azo dye as a model pollutant, was conducted under simulated solar-light irradiation. β-CD-assisted NiMoO 4 rod-like NCPHC resulted in a 2-fold higher photocatalytic activity in comparison to the other fabricated morphologies and also a 1.5-fold higher photocatalytic efficiency than that of a commercial nano-ZnO, that can be attributed to the greater availability of hydroxyl functional groups and defects in the crystalline structure. Moreover, the photo-decolorization rate was assessed by first-order, second-order, parabolic-diffusion, and modified-Freundlich kinetic models. Consequently, the result proved that photocatalytic performance is highly depends on the morphology and crystalline-phase of the NCPHCs. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Reactive Black 5 and Reactive Red dyestuffs have been synthesized in the laboratory. The synthesis was obtained by diazotization of 1-amino-phenyl-4-beta hydroxyethyl sulfone sulfate ester and coupling with 1-amino-8-hydroxynaphthalene-3,6-disulfonic acid (H-acid) (mole ratio 2:1) (Reactive Black 5Na) and (mole ratio 1:1) (Reactive Red Na). The dye was purified-concentrated by ultrafiltration technology and the permeate (waste) was used as dye bath in the exhaustion of cotton and polyamide with the sodium salt of Reactive Black 5 (RB5Na) and the sodium salt of Reactive Red (RRNa). The same dyeing was also made with fresh water as dye bath. Fastness properties were also measured in both cases and the results were compared. Color measurement results of the dyeings were almost the same when the waste as dye bath was used. [ABSTRACT FROM AUTHOR]

The present paper investigates the effects of breed and age on the dye fixation on wool using a reactive dye. It also examines the optimization of the dyeing process realized using the response surface methodology. The dyeing step was carried out on raw wool using the bichromatic blue dye reagent Cibacron P-3R (C.I. Reactive Blue 49). The factors affecting the dyeing process, such as ammonia concentration, temperature, and the duration of the dyeing time, were studied using the response surface methodology. The performance of this dyeing process was evaluated by measuring the color yield (the dye fixation). The results have shown that the age and the breed of sheep have a significant effect (P <0.05 %) on the dye fixation rate. This can be attributed to the differences in the amino acids of wool. Additionally, it has been found that the youngest wool and the Sicilo-Sarde breed always yielded the best dye fixation while the oldest wool and the Fine Queue of west breed (QF) have the lowest dye fixation. Using the response surface methodology, this research has proved that the best dyeing quality for the QF is obtained by using an amount of ammonia of 20 ml, a dyeing duration of about 60 min, and a dyeing temperature of about 100 °C. [ABSTRACT FROM AUTHOR]

This study was undertaken to evaluate the adsorption of Reactive Black 5 dye (RB5), in aqueous solution, onto MCM-41 mesoporous silica nanoparticles (MSNs) functionalized with 3-aminopropyltriethoxysilane (APTES) by two methods: co-condensation and post-synthesis. The morphological and surface properties of both functionalized materials were compared by SEM, SAXS, N2 sorption and XPS characterization techniques. Sorption experiments were performed in order to determine the effect of pH, contact period and initial concentration of aqueous RB5 on the adsorption properties of bare- and both types of amino-MSNs. The results show that there exist morphological changes in the nanoparticles according to the type of functionalization synthesis, i.e. loss of hexagonal structure in co-condensation method and more density of amino groups on the surface of post-synthesis functionalized materials. The adsorption of RB5 on both type of materials is independent of the pH since they present adsorptions close to 100% in the evaluated pH range. The best fit of the data from adsorption kinetic studies is a pseudo-second-order model, being the material functionalized by the co-condensation method, which presents a higher adsorption rate because of its greater pore volume. The adsorption isotherms fitted well to the Langmuir model, with the amino-MSNs functionalized via the post-synthesis method presenting a higher capacity of adsorption, due to a greater density of amino groups on its surface, thereby facilitating their interaction with the RB5 molecules. Altogether, the results indicate that the type of functionalization synthesis affects the morphological characteristics of the nanoparticles and these, in turn, modify their adsorption properties. [ABSTRACT FROM AUTHOR]

Abstract Ozonation is increasingly used for color fading dyed textile nowadays. This paper studied the overall effect of color fading ozonation on the color yield of cottons dyed by Reactive Blue FL-RN (RB-RN), Reactive Red FL-2BL (RB-2BL) and Reactive Yellow FL-2RN (RY-2RN) respectively. In which, the color fading effects in terms of reflectance curves, L*a*b* values and the kinetic studies regarding K/S values are investigated. Experimental analysis has been carried out for finding the effects of pH, temperature and water pick-up on the ozonation process. It is found that color fading ozonation has stable performance in the respects of lightness and color difference on treated cottons, and the decolorization reactions in ozonation are assumed as pseudo secondary order (for cottons dyed by RB-RN and RY-2RN) and pseudo third order (for cottons dyed by RR-2BL) respectively. It is also found that alkaline as pH in the range of 7–10 and higher temperature range from 40 to 80 °C are suggested along with a water pick-up around 75% to promote the color fading efficiency in color fading with respect to the dyes in this study. [ABSTRACT FROM AUTHOR]

In this work, a series of magnetic activated carbon/nanodiopside (Fe3O4/AC/Diop) nanocomposites were synthesised and used for the removal of reactive green KE-4BD dye from the aqueous solution. After preparation of nanodiopside by sol-gel method and activated carbon from coconut husk, first, Fe3O4/AC composite was prepared by in situ synthesis of Fe3O4 nanoparticles between activated carbon pores, and then, different percentages of Fe3O4/AC/Diop nanocomposites were prepared by simple mixing of Fe3O4/AC composite and Diop in ethanol. Formation of Fe3O4/AC and Fe3O4/AC/Diop composites was characterised by FTIR, field emission scanning electron microscopy, BET, XRD and vibrating sample magnetometer analyses. Thermogravimetric analysis was used to show the adsorption capacity of the adsorbent more accurately. Effects of amount of adsorbent, initial pH, contact time and dye concentration on reactive green dye removal were also studied using central composite design. Optimal conditions for maximum reactive green KE-4BD dye adsorption (98.35%) process were as follows: pH= 4.90, adsorbent amount: 0.015 g, dye concentration: 37.17 mg/L and contact time: 10.12 min, respectively. In addition, the adsorption kinetics, thermodynamics and isotherms were examined. Adsorption isotherms (qmax: 344.827 mg/g), kinetics and thermodynamics were demonstrated that the sorption processes were better described by the pseudo-second-order equation and the Langmuir equation. [ABSTRACT FROM AUTHOR]

Abstract In this study, SBA-15 mesoporous silica was synthesized and functionalized with cross-linked polyacrylic acid and used to remove Reactive Orange 16 (RO16) from aqueous media. X-ray diffraction (XRD), filed emission scanning electron microscope (FE-SEM), fourier transform infrared spectrometer (FT-IR), thermo gravimetry analysis (TGA) and BET method were used to study the characteristics of the resulting nanocomposite (SBA-15/CPAA). The effective parameters on dye removal, including pH, contact time, temperature and adsorbent dosage were investigated and optimized. The optimum condition was: pH = 2, adsorbent dosage of 0.03 g and contact time of 60 min at 25 °C. Uv–Vis spectrophotometer was used to determine the amount of residual dye in solution. Multilayer Perceptron (MLP), Redial Basis Function (RBF) and Group Method of Data Handling (GMDH) models have been applied for predicting adsorption value according to the amount of pH, dosage, temperature, concentration and contact time. Comparison of these models revealed that the MLP model was more accurate than the other two models. Highlights • New super adsorbent was synthesized and used for dye removal in batch systems. • ANN and the GMDH models have been used for prediction. • ANN model produce more accurate results than GMDH model. [ABSTRACT FROM AUTHOR]

Abstract Reverse micelles using nonionic poly(ethyleneglycol) (PEG)-based surfactant as building block were introduced to encapsulate reactive dye for cotton dyeing. The morphological transition of reactive dyes from well-dispersive spherical form into highly agglomerated form via various surfactant-to-co-surfactant molar ratios and surfactant-to-water molar ratios have been preliminary investigated. The dyeing properties of cotton has been analyzed in terms of dispersion of reverse micelle structure from transmission electron microscopy, identification of chemical signatures of dye-cotton interaction from Raman spectroscopy, color strength and relative levelness. The reverse micellar structures under both highly dispersed and agglomerated forms are in good agreement with color strength and levelness data. The optimization of surfactant conditions can be considered as major parameters for investigating the quality of cotton dyeing including color strength and levelling conditions. Highlights • Reverse micelle was introduced to encapsulate reactive dye for cotton dyeing. • Reverse micellar structures are highly dispersed and agglomerated forms. • Good color strength and levelness data were obtained. [ABSTRACT FROM AUTHOR]

Copyright of Wool Textile Journal is the property of National Wool Textile Science & Technology Information Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The influence of initial metal ion concentration and temperature on the adsorption of Zn(II) from aqueous solution onto amino ethyl cellulose (AEC) functionalized with Orange 16 reactive dye, was examined. Batch experiments were performed at pH of 4.0 and adsorbent dose of 8.0 g/L previously established as optimum, ranging the initial Zn(II) concentration between 22.74-181.92 mg/L and temperature between 2 and 60 oC. Three isotherm models (Langmuir, Freundlich and Dubinin – Radushkevich) were applied to the equilibrium data and the fitted parameters were used to determine the thermodynamic parameters of adsorption process. The adsorption equilibrium was well described by the Langmuir model. Maximum adsorption capacity of functionalized AEC for Zn(II) ions slightly increase with increasing of temperature, from 33.56 to 36.50 mg/g. In addition, the adsorption energy, calculated from Dubinin - Radushkevich model, indicate that the Zn(II) uptake process occurs via electrostatic interactions. Thermodynamic studies indicated that adsorption of Zn(II) onto functionalized AEC is and endothermic process (ᐃH = 9.98 kJ/mol) and spontaneous (ᐃG = - 14.50 ÷ - 19.64 kJ/mol), in the studied temperature range. [ABSTRACT FROM AUTHOR]

Anew technique represented in this study for evaluating the performance of dyeing cotton fabrics using infrared (IR) heating technique compared to conventional exhaust dyeing method. The effect of this new technique has been studied on the color strength (K/S), color fastness properties, tensile strength and elongation of the dyed cotton fabrics made of two Egyptian varieties Giza 90 and Giza 95 using Procion H-EXL blue reactive dye with concentrations 2%, 4% and 6% . The color strength values of the infrared heating technique in dyeing were better than those of the exhaust dyeing obtained using the same dye concentration 4% and the same recipes. Also the results for dyeing using infrared heating technique had no bad effect on the color fastness or on the dyed cotton fabric mechanical properties. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract The commercially available Fe0 aggregate has advantages of low-cost, fast-effective decontamination, reusability, and ease of operation. However, little study has been done on the performance of Fe0 aggregate as a catalyst in degradation of azo dyes, particularly used in persulfate (PS) oxidation process. This study investigated decolorization of a reactive azo dye, Remazol Golden Yellow (RGY, Reactive Orange 107), by persulfate oxidation activated with Fe0 aggregate. RGY decolorization was not effective in ultrasound-activated, heat-activated, and base-activated persulfate oxidation; however, a significant decolorization improvement was achieved by applying Fe0 aggregate to activated persulfate (PS/Fe0). Decolorization was strongly influenced by pH, Fe0, persulfate dosages and temperature. The suitable conditions for RGY decolorization were pH 6.0, PS 5 × 10–3 M, and Fe0 0.5 g/L. This condition yields 98% color removal of 100 mg/L RGY solution within 20 min treatment; the azo bonds of RGY were completely broken down. RGY decolorization followed the first-order kinetics. Activation energy of the PS/Fe0 system was 0.479 kJ/mol, suggesting the temperature dependence of RGY decolorization is small. The presence of inorganic salt in RGY solution had an adverse effect on decolorization. The inhibitory effect of various inorganic salts on decolorization followed the sequence of Na 2 HPO 4 ≫ NaHCO 3 ≫ NaClO 4 > NaCl > NaNO 3 > NaClO 4 > no salt. The Fe0 aggregate was reusable and a satisfactory decolorization efficiency was achieved with the repeated use of Fe0 for five times. The PS/Fe0 process provides an efficiency and effective technology for RGY decolorization. [ABSTRACT FROM AUTHOR]

Abstract Dyeing effluents have become a vital source of water pollution. Due to the xenobiotic properties and toxicity to all life forms including humans, removal of undesirable color and associated toxicity is crucial. In this study, five dye decolorizing bacteria were isolated from dyeing effluent using selective enrichment culture in Bushnell-Haas (BH) medium amended with co-substrate (i.e. glucose, yeast extract) and 100 mg L−1 of each commercially available reactive dyes viz. Novacron Orange FN-R, Novacron Brilliant Blue FN-R, Novacron Super Black G, Bezema Yellow S8-G and Bezema Red S2-B. The isolated bacteria were identified and assigned as Neisseria sp., Vibrio sp., Bacillus sp., Bacillus sp. and Aeromonas sp. based on their phenotypic (cultural, morphological, physiological and biochemical characteristic) observation. The dye decolorization efficiency was estimated spectrophotometrically up to 6 days of static incubation at 37 °C and observed that all of the isolates were unable to induce decolorization in absence of co-substrate. In case of monoculture, decolorization percentage varies from no visible decolorization (Bezema Red S2-B by Ek-5) to highest 90% decolorization (Novacron Brilliant Blue FN-R by Ek-13) whereas the decolorization percentage of bacterial consortium varies from 65% (Bezema Yellow S8-G) to 90% (Novacron Brilliant Blue FN-R and Novacron Super Black G). The study outlines the co-substrates mediated decolorization process where bacterial consortium proved as efficient dye decolorizer than that of the monocultures. This finding confers possibility of using novel microbial consortium for biological treatment of disreputable dyeing effluents. [ABSTRACT FROM AUTHOR]

Copyright of Wool Textile Journal is the property of National Wool Textile Science & Technology Information Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A novel magnetic anion exchange microbead (NAEM) with excellent reuse and anti-fouling performance was developed, and used for removal of an reactive dye sunset yellow (FCF). The NAEM initial adsorption rate was 16.7-, 25.8-, 31.6-, and 31.6-fold that of commercial IRA-958, D201, A520, and IRA-900 resins, respectively. The adsorption of FCF on different anion-exchange resins appeared to be multilayered, implying physical adsorption also contributes to FCF removal. The polyacrylic resin matrix exhibited higher affinity than the polystyrene matrix towards FCF. The equilibrium adsorption capacity for FCF at 298 K was in the following order: NAEM (1.95 mmol/g) > IRA-958 (1.01 mmol/g) > D201 (0.85 mmol/g) > A520 (0.81 mmol/g) > MAER (0.78 mmol/g) > IRA-900 (0.59 mmol/g). NAEM reinforced the anti-interference capacity of FCF adsorption when the concentrations of NaCl or Na 2 SO 4 were lower than 20 mmol/L. After 10 cycles of regeneration, the FCF adsorption capacity of NAEM was 1.76-, 2.79-, 2.81-, 3.05-, and 5.26-fold higher than MAER, IRA-958, D201, A520, and IRA-900, respectively. The high adsorption capacity and excellent reusability may facilitate the practical applications of NAEM in wastewater treatment against reactive dyes. [Display omitted] • Hydrophilic resin matrix and large porous structure facilitate the removal of FCF. • The initial FCF adsorption rate of NAEM is ten-fold that of commercial resins. • NAEM maintains stable FCF adsorption capacity in the presence of 20 mmol/L NaCl or Na 2 SO 4 . • Desorption rates of NAEM are nearly 100 % during successive reuse. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mesoporous MgO was produced from solid waste of ductile iron casting by sonication. • The nanoparticles exhibited a mesoporous structure with mean pore size of 3.7 nm. • The adsorption of reactive dyes was carried out from industrial effluents. • R Red 195 is better adsorbed than R Blue 222 over mesoporous MgO. • The successive uptake of reactive dyes is due to extended surface area, 105.8 m2/g. Porous MgO nanoparticles were fabricated through the conventional, and ultrasound-assisted precipitation followed by heat treatment at 500 °C. The uptake of reactive dyes, R Blue 222, and R Red 195, was examined by adding adsorbents into the industrial effluents. When precipitation is carried out under sonication, the material consumption to achieve the maximal efficiency, ∼95 %, decreases 33.3 wt%, in comparison to that for the powder fabricated conventionally. The development of mesopores, 3.7 nm, provides an extended surface area, 105.8 m2/g, improving adsorbent performance. [ABSTRACT FROM AUTHOR]

In this study, the adsorption of active carbon derived from waste sesame seeds coated with polyvinyl alcohol (AC/PVA) was investigated for removing red 198 and blue 19 reactive dyes from textile effluents. The batch process was carried out to identify such parameters as pH, adsorbent dose, contact time, and initial dye concentration involved in the dye removal adsorption capacity of AC/PVA. Also, batch kinetic and isotherm experiments were conducted. Results indicated that the maximum dye removal was obtained in an acidic pH over 90 min of contact time and that adsorption rates followed the pseudo-second-order kinetics. Blue and red dye concentrations were determined using the spectrophotometric method at 590 and 517 nm, respectively. It may be concluded that AC/PVA is capable of removing blue and red reactive dyes and can be used as an efficient, cheap, and accessible adsorbent for treating textile effluents.

Environment preservation is a common worry not only for people but for companies as well. Industry is more and more concern about the necessity of developing new and more respectful processes. Dye is one of the most important processes in the textile industry but it is also considered as no too safe regarding environment issues. This process uses large amounts of water and generates big volumes of wastewater. Following this issue, new regulations and laws emerge to control the waste generated. This leads to the companies and increased costs in terms of wastewater treatments and high water consumption. In this research we compare two systems on garment finishing application, the conventional bath process and the new Ecofinish system that is able to save water and product. To compare these processes, we carried out a reactive dyeing using both systems in order to determine the quality differences in the final product. For this purpose, the samples have been tested to washing and rubbing fastness, according to UNE EN ISO 105 C10 and UNE- EN ISO 105 X12 standards, respectively. This study confirms that this system achieves water savings and reduces the wastewater produced, getting a good dyeing. This process can be considered as an alternative to the conventional one.

The dyeing behaviour of UV irradiated cotton and polyester fabrics using multifunctional reactive and disperse dyes has been investigated. The plain, woven, mercerized, bleached, cotton and polyester fabrics were exposed to UV radiation (180 w, 254 nm) for 30, 60, 90 and 120 min. Dyeing was performed using irradiated fabric with a dye solution of un-irradiated reactive and disperse/azo dyes. The dyeing parameters such as, temperature, time, pH and salt concentration have been optimized. The colour strength values of dyed fabrics were evaluated by comparing irradiated and un-irradiated cotton and polyester fabrics in CIE Lab systems using spectra flash SF600. Finally ISO standard methods were employed to observe the effect of UV radiation on fastness properties. It was found that UV radiation has a potential to improve the colour strength values of cotton and polyester fabrics by using reactive and disperse dyes.

Digital inkjet printing has been widely used in textile industry. The quality of dye solutions and ink-jet droplets limits the ink-jet printing performance, which is very important for obtaining high-quality ink-jet printing images on fabrics. In this paper, we introduced diethylene glycol (DEG) into the dye solutions of Reactive Blue 49 and Reactive Orange 13, respectively, and investigated the interaction between dye chromophores and DEG molecules. Results indicated that the dye chromophores were featured in the aggregation. Adding DEG into the dye solution could effectively disaggregate clusters of reactive dyes, and eliminate satellite ink droplets, thus improving the resolution of the ink-jet printing image on fabrics. Under the same DEG concentration, the disaggregation effect was more obvious in Orange 13 than in Reactive Blue 49. Higher DEG concentration was required in Reactive Orange 13 solution for creating complete and stable ink drops. The surface tension and viscosity of the dye solutions were measured, and printing performance on cotton fabrics was evaluated. The interaction mechanism between dye chromophores and DEG molecules was also investigated. Results from this work are useful for high-quality ink-jet printing images on fabrics.

Dyes, being potential pollutants, need alarming attention for their degradation from wastewater. Advanced oxidation processes (AOPs) are among the most effective methodology for the degradation of pollutants. In the present study, the heterogeneous photo-Fenton catalysts (ZnFe _2 O _4 and graphene oxide based ZnFe _2 O _4 composite) were prepared and used to study the degradation of synzol red reactive dye. The prepared catalysts were well characterized by using SEM, FTIR and XRD analysis. The effect of various parameters like pH, catalysts dosage, H _2 O _2 dosage, effect of dye concentration and irradiation time during heterogeneous photo-Fenton processes was studied. The results showed 57% and 94% degradation of dye under optimized conditions (e.g. pH = 3, Catalysts dose = 75 mg l ^−1 for ZnFe _2 O _4 and 50 mg l ^−1 for GO- ZnFe _2 O _4 , H _2 O _2 dose = 27 mM and irradiation time of 60 min) was observed for ZnFe _2 O _4 and GO-ZnFe _2 O _4 , respectively. A comparison of degradation potential of catalysts using various light sources like UV-254 nm, ambient solar light and white LED, was studied. The current findings support the application of solar and LED light for the degradation of organic pollutants in wastewater. The stability and reusability of these catalysts for the degradation of the dye were also studied. The GO- ZnFe _2 O _4 composite showed negligible iron leaching and no considerable reduction in degradation efficiency upto six consecutive cycles of reusability. It has been found that the composite (GO–ZnFe _2 O _4 ) showed enhanced degradation of dye as compared to ZnFe _2 O _4 .