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Poseben problem odpadkov v tekstilni industriji predstavljajo odpadne tehnološke vode, predvsem tiste, ki nastajajo pri plemenitenju tekstilij. Te odpadne vode so močno obremenjene, vsebujejo različne kemikalije in tekstilna pomožna sredstva, imajo ekstremne pH-vrednosti in visoke KPK in BPK vrednosti, različne tipe organskih barvil, kar povzroča obarvanost, vsebujejo fosfate, sulfate in ostale soli, tenzide, maščobe in olja ter različne tipe težkih kovin. Tekstilne odpadne vode so zelo heterogene po sestavi, zato je čiščenje takšnih voda kompleksna naloga, za katero ni idealne in v naprej izdelane metode. Glede na proizvodni proces je potrebno izbrati fleksibilno in ekonomsko upravičeno tehnologijo čiščenja. Pri izbiri tehnologije čiščenja odpadnih voda moramo upoštevati njihovo količino in kakovost, ki jo ovrednotimo s specifičnimi in sumarnimi ekološkimi parametri.

Alkaline anion exchange membrane fuel cells (AAEMFC) are attracting ever-increasing attention, as they are promising electrochemical devices for energy production, presenting a viable opponent to the more researched proton exchange membrane fuel cells (PEMFCs). Consequently, great progress has been made in the area of designing and developing synthetic or naturally-derived anion exchange membrane (AEM), the properties of which have been discussed in this review, i.e. ionic conductivity, ion exchange capacity, fuel crossover, durability, stability and cell performance. Major groups of natural polymers (e.g. chitosan (CS)) and nanocellulose, together with modification/crosslinking routes, have been mentioned as more ecologically and economically viable raw materials for AEM processing compared to synthetic ones. Performances of fuel cells are also discussed, with different fuels used as anode feeds. Although the AEMFC technology is promising, the longevity challenges remain, originating from the still-limited long-term stability of hydroxide-conducting ionomers, particularly when operating at higher cell temperatures.

People have been accompanied by colours throughout the history and through all periods of life. In different eras, colours were also associated with status symbols of different social classes or mythological beliefs. We are often addressed emotionally by colour combinations, since colour perception is always and exclusively a sensorial experience. Various colour combinations can have a pleasant effect on us or leave us cold as well as in a state of shock. All of the above, presented the starting point of this research. Detection and perception of sensations through colour was accomplished by preparing a questionnaire related to 12 selected colours. The research included 302 participants from Slovenia, of both sexes and different ages, born from 1940 to 2004. From the obtained results, it could be concluded how popular a certain colour is in a material, design and spiritual sense. Moreover, the results were validated and compared regarding the gender and age of participants, and further compared with the results of previous studies.

The proposed paper describes the influence of woven fabric constructional parameters (type of weave, relative fabric density) and colouration (obtained by eco-friendly dyeing) on the solar transmittance of cotton woven fabrics in the range of 210–1200 nm. The cotton woven fabrics in their raw state were prepared according to Kienbaum’s setting theory, at three levels of relative fabric density and three levels of the weave factor, and then exposed to the dyeing process with natural dyestuffs (beetroot, walnut leaves). After ultraviolet/visible/near-infrared (UV/VIS/IRA) solar transmittance and reflection in the range of 210–1200 nm were recorded, the influence of the fabric construction and colouration were analysed. The guidelines for fabric constructor were proposed. The results show that the walnut-coloured satin samples at the third level of relative fabric density provide the best solar protection in the whole solar spectrum. All the tested eco-friendly dyed fabrics offer good solar protection, while only raw satin fabric at the third level of relative fabric density can be classified as solar protective material with even better protection in IRA region than some coloured samples.

The presented study assesses the efficiency of selected adsorbents, zeolite 4A in two particle sizes and pelletized activated carbon (AC), for the potential removal of color, chemical oxygen demand (COD), total organic carbon (TOC) and metals from wastewaters after natural wool dyeing. Firstly, the natural coloring compounds were extracted from dried common walnut (Juglans regia) leaves and used further for exhaustion dyeing of wool fibers, together with three different metallic salts in two concentrations (meta-mordanting). Effluents with higher mordant concentration were additionally treated according to a shake-flask adsorption experiment. The obtained results revealed efficient removal of exceeded metallic ions by zeolite (up to 94.7%), on account of their superior ion exchange capability as compared to AC. The zeolites also reduced turbidity and electrical conductivity significantly. On the other hand, AC was more efficient for the reduction in organic pollution, COD up to 96% and TOC up to 95%, due to its higher specific surface area and total pore volume, and, thus, higher potential for adsorption of different compounds in comparison to 4A. All three proposed adsorbents lowered wastewaters’ coloration remarkably, up to 78% (AC) and up to 71% (4A), depending on the type of effluent/mordant and inspected wavelength; although, the spectral absorbance coefficient (SAC) values remained highly above the limit values for discharge of wastewaters into watercourses.

The presented research examined five adsorbents, i.e., zeolite 4A, a mixture of three zeolites (4A, 13X, and ZSM-5), natural zeolite (tuff), activated carbon, and peat, and their potential capability for removal of exceeded ions of lead (Pb), antimony (Sb), sulphates (SO42−), and fluorides (F−) from real wastewater generated in the crystal glass industry, which was previously treated in-situ by flocculation, with the aim to attain the statutory values for discharge into watercourses or possible recycling. The screening experiment evidenced that the tuff was the most suitable adsorbent for the reduction of Pb (93.8%) and F− (98.1%). It also lowered wastewater’s pH sufficiently from 9.6 to 7.8, although it was less appropriate for the reduction of Sb (66.7%) as compared to activated carbon (96.7%) or peat (99.9%). By adjusting the pH of the initial wastewater to pH 5, its adsorption capacity even enlarged. Results from the tuff-filled column experiment revealed reduction of Pb up to 97%, Sb up to 80%, and F− up to 96%, depending on the velocity flow, and thus it could be used for post-treatment (and recycling) of wastewaters from the crystal glass industry. Moreover, the system showed an explicit buffering capacity, but negligible reduction of the SO42−.

This work concerns freeze-dry processing of CNF aerogels, including aluminum hydroxide trihidrate (Alolt) particles and Sodium silicate, as active and passive flame retardants, respectively. Alkalinity of Sodium silicate promotes stability, dissociation and co-precipitation of Al(OH)3 component onto CNFs. The (auto)fluorescence-enabled confocal microscopy enabled visualization of anisotropic microstructure with open and closed-cell segments, depicting the Alolt as single and aggregated particles. Low thermal conduction (~ 0.045 W/mK) was estimated, irrespective of composition, while Alolt was found to reduce (by 30%) the aerogel moisture content. Sodium silicate promotes char formation as passive action, reducing the evolution of gaseous species, while burning test shows complete flame retardation through active endothermic reaction assigned to Alolt. Additive combinations did not amplify, nor diminish, the flame retardant effect of particular component, yet affected positively the elastic modulus. Considering simple “green” processing, low additive load, and high insulation and flame retardant efficiency, these aerogels hold promise as thermal insulation materials.

The main objective of the presented research was to study the possibility of using natural colourants obtained through the aqueous extraction of fresh leaves from the Junglans regia (J. regia), or common walnut tree, for the dyeing of wool yarn. A unique principle was explored by combining the phases of extraction and mordanting into one with the aim of shortening the dyeing procedure, while at the same time extracting more colouring components. Spectrophotometric studies revealed the signifi cant impact of both mordant addition and dye-bath pH on the absorbance curve and thus on the colour and K/S values of the dyed samples. A meta-ordanting technique using ferrous sulphate produced a greater depth of shade at a wavelength of 400 nm, with respect to the concentration of mordant and the liquid ratio of the extraction. Finally, wool yarn dyed with pure leaf extracts exhibited a potent inhibiting activity against Candida albicans (C. albicans) with a moderate reduction rate of 59%, and an inhibited response against Staphylococcus aureus (S. aureus) with a low reduction rate of 38.6%.

Prisotnost barvil v odpadni vodi je nesprejemljiva tako iz estetskega kot tudi iz ekološkega stališča. Problematika prvega izhaja iz dejstva, da so odpadne vode, ki vsebujejo barvila, intenzivno obarvane že pri zelo nizkih koncentracijah barvil. Bolj pereča kot estetska je okoljska problematika barvil v odpadni vodi. Objektivno tveganje, ki ga predstavljajo za okolje, je odvisno od strukturnih in fizikalnih karakteristik barvil, njihove koncentracije ter časa izpostavitve v okolju. V okviru predmeta se prouči razpoložljive tehnologije čiščenja obarvanih vod, kar pa kaže na to, da ni enostavnih, učinkovitih in hkrati cenovno sprejemljivih načinov čiščenja tako kompleksnih odpadnih vod, kot so obarvane odpadne vode.

Vaje »Sodobni postopki barvanja in barva« obravnavajo sistematiko in nomenklaturo barvil, fizikalno kemijo barvalnih procesov ter uporabo naprednih materialov in tehnik pri procesu barvanja. Največji del je posvečen posebnim postopkom, ki omogočajo sodoben način barvanja ob istočasnem doseganju višjega nivoja kakovosti tako v smislu ekologije, kot v doseganju več funkcionalnih lastnosti materialov in barvanju z naravnimi barvili. Postopki, ki jih posebej proučujemo so barvanje pri pogojih super kritičnega CO2, barvanje ob souporabi ultrazvoka ali predhodne plazma obdelave in barvanje s funkcionalnimi barvil. Ta vrsta barvil nam omogoča posebnosti kot so: termokromija, fotokromija, elektrokromija, solvatokromija in ostale učinke povezane z uporabo teh barvil.

Multiwall carbon nanotubes were coupled with titanium dioxide (in different mole ratios of titanium and carbon) at the nano-scale, using a simple sonochemical and calcination process. The titanium dioxide-multiwall carbon nanotubes nanocomposites were for the first time surface modified with an innovative biotechnology-based reaction by using laccase to activate and covalently graft gallic acid dimers/oligomers/polymers on the nanocomposite surface in order to impart new functionalities and to minimize the nanocomposites’ toxicity. Structure of the titanium dioxide-multiwall carbon nanotubes, before and after surface modification, was investigated with X-ray powder diffraction, infrared, and UV-visible diffuse reflectance spectroscopy analysis, and scanning electron microscopy. The results indicated preferential formation of anatase titanium dioxide on one hand and covalent grafting of gallic acid dimers/oligomers/polymers functionalities on the nanocomposite surface, on the other. After modification, the antioxidant activity was analyzed using 2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and photocatalytic activity toward the liquid-phase degradation of methylene blue in aqueous solution under both UV and visible light irradiation. Up to 98% antioxidant activity of the surface modified nanocomposites was established after 24 h of incubation, whereas non-modified nanocomposite induced the formation of the ABTS•+ radicals. In addition, 1.3-2.8-fold reduction in photocatalytic activity was achieved, depending on the irradiation. Accordingly, the gallic acid dimers/oligomers/polymers modified titanium dioxide-multiwall carbon nanotubes appear to simultaneously exhibit photocatalytic activity with an ability to scavenge free radicals, and can thus be considered as engineered nanoparticles with low toxicity.

The aim of this research was to apply three different types of zeolites and the combination thereof in the form of a very fine powder, together with different chemicals and additives on polyamide knitted fabric according to an industrially acceptable exhaustion procedure in order to study changes in the morphology, optical properties and wettability of surfaces. Zeolites were analysed using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and gas physiosorption. Additionally, the morphology of zeolite-coated surfaces was examined closely using SEM, while changes in molecular-chemical level were examined by means of IR spectroscopy. Optical properties were studied using CIE colour measurement and diff use reflectance profi le determination, while the hydrophilic/hydrophobic character was examined using goniometry. The obtained results show the suitability of the employed exhaustion procedure, depending on the type of zeolite and the composition of the treatment bath. The results also provided evidence of the enhanced wettability of PA fabrics using 4A and 13X zeolites in combination with selected additives.

Fusing multiwall carbon nanotubes (MWCNTs) with TiO 2 at the nano-scale level promotes the separation of those electron–hole charges generated upon UV and daylight irradiation. In this study, we investigated facile sonochemical synthesis, combined with the calcination process for the preparations of TiO 2 -MWCNT composites with different mole ratios of titanium and carbon. In order to produce stable nano dispersions we exploited an innovative biotechnology-based approach for the covalent functionalizations of TiO 2 -MWCNTs with in-situ synthesized soluble phenoxazine dye molecules. The none and functionalized TiO 2 -MWCNTs composites were analyzed by a range of analytical techniques including XRD, Raman, XPS, SEM and UV–vis diffuse reflectance spectroscopy (DRS), and dynamic light scattering (DLS). The photocatalytic activity was evaluated toward the liquid-phase degradation of MB in aqueous solution under both UV and visible light irradiation. TiO 2 -MWCNTs with optimized mole ratio exhibit much higher photocatalytic activity and stability than bare TiO 2 . The as-prepared TiO 2 -MWCNTs photocatalyst possessed good adsorptivity of dyes, extended light absorption range and efficient charge separation properties simultaneously. The results indicated that the soluble phenoxazine dyes and amino-benzenesulfonic acid monomers were covalently grafted on to the surfaces of TiO 2 -MCNTs, which promoted good aquatic dispersibility and extended light absorption, resulting in increased photocatalytic efficiency.

The optimized preparation of novel electrospun nanofibrous composites from cellulose acetate (CA) and ultra-high silica zeolites (UHSZ) are reported as a promising material for the adsorption of Volatile Organic Compound (VOCs). Two types of UHSZs, i.e. silicalite and USY were prepared by hydrothermal crystallization while the fabrication of composites was performed using single needle and needle-less electrospinning systems, demonstrating the scalability of the composite fibres’ manufactured. Herein, factors such as properties of spinning solutions and electrospinning process parameters were studied, as well as interactions between the CA and UHSZs. In addition, Quartz Crystal Microbalance - Dissipation technique (QCM-D) was employed with an aim to study the adsorption behaviour of newly developed composites using ammonia as a model pollutant. The QCM-D data revealed that the presence of UHSZs in the CA materials increased adsorption capacity, designating CA/UHSZ composites as potential materials suitable for a large-scale removal of VOCs from polluted air.

The aim of this work was to investigate the color change of cotton fabrics with stainless steel yarns incorporated. In order to establish the impact of conductive yarns’ composition properties in the fabric, concentrations and two different dyeing profiles based on direct and reactive dyes chemistry were applied. The success of this novel e-textile design was evaluated colorimetrically with two different dye concentrations as well through various linear electrical resistances to obtain solid statistical conclusions. The dyed samples were colorimetrically evaluated and the electrical resistances of conductive yarns inside the fabric structure were compared and discussed statistically before and after dyeing. The results provided evidence that dyeing has great influence on electrical resistances of conductive yarns used as transmission lines for electro-textile applications. The greatest changes in electrical resistances were observed with samples including thin conductive yarns and untwisted conductive yarn after dyeing processes. Additionally, it can be concluded that the presence of stainless steel conductive threads significantly retards the dyeing processes depending on the dyestuff concentration and weave type, resulting in major color differences, especially when plain weave type is used or the dyestuff concentration is less than 1% for twill and sateen weaves.

The purpose of this research was to apply four stable colloidal dispersions, combining di erent TiO2 coreshell nanoparticles, onto polyester fabric, according to exhaustion procedure, in order to enhance fabrics' water and moisture absorption properties. Firstly, all colloidal dispersions were analysed using transmission electron microscopy (TEM) and dynamic light scattering (DLS) and secondly, the morphologies of TiO2 modi ed PES surfaces were evaluated by scanning electron microscopy (SEM). In addition, the superhydrophilic character of brous surfaces was investigated by water contact angle measurement. For this purpose, dynamic tensiometry was employed by measuring the changes in the net force on a surface during the repeated immersion and emersion of a solid into a probe liquid. The obtained results show excellent wettability of TiO2 upgraded PES fabrics depending on the type of applied nano-sized TiO2-hybride.

The appearance and hand of end-use fabrics has become more and more important when purchasing textile fabrics. The finishing parameters have complex influences on the large number of changes that occur in fabric properties during finishing processes. This study focused on the influences of different finishing parameters on mechanical and surface properties in order to discover the most appropriate finishing process according to the requirements of fabric handle and appearance. The KES-F system was used to evaluate fabric hand objectively, as well as the mechanical and surface properties of a woven wool fabric. Four finishing processes were selected, which differed in relation to the temperature when drying (T1=160 C, T2=180 C) and processing conditions during autoclave decatizing (T1=95 C, p1=0.4 bar, T2=110 C, p2=1 bar). The effect of the influential parameters inside four different finishing processes on the mechanical properties and hand of a selected woven fabric was evaluated using the analysis of variance. The results show that tensile properties are much more influenced by the belt pressing process while bending and shear properties are influenced by continuous decatizing process, which is the process that mostly improves fabric stability at the beginning of the dry finishing cycle. When the primary and total hand values were observed, it could be seen that applying chemicals during belt pressing had some consequences, the impacts of which could be observed directly in the resulting hand values.

The aim of the presented work was to study the effects of TiO2–SiO2 nanoparticles on the hydrophilicity as well as colouration ability of polyester fabric during high-temperature disperse dyeing. Various analytical techniques were employed to characterize three TiO2–SiO2 dispersions with different SiO2 weight percent. In addition, one-bath exhaustion procedure was accomplished by combining TiO2 dispersions and three disperse dyes in two concentrations, respectively. Finally, the dyed/nano-upgraded samples were subjected to artificial UV light with the intention of establishing any undesired photo-fading behaviour of applied dyes on account of TiO2 presence. The results provided evidence of enhanced wettability at low SiO2 content, and on the other hand, pale depth of shade when the nanoTiO2-hybrides were attended, regarding the type of dye and its concentration. Moreover, UV irradiation significantly influenced the hue, brightness, chroma, and colour strength, although the higher SiO2 amount suppressed the photocatalytic activity of nanoTiO2 and thus, diminished the oxidative dye-fading.

The purpose of this study was to assess and compare the durability of TiO2-SiO2 coatings applied in three concentrations onto two lightweight cellulose-based fabrics diverse in the composition against two external factors, repeated washings and prolonged intensive UV irradiation, by observing the changes in surface morphology, investigation of optical properties, and identification of specific molecular vibrations. The scanning electron microscopy (SEM) micrographs, diffuse reflectance spectroscopy (DRS) profiles and fourier transform-infrared (FT-IR) spectra implied equal distribution of TiO2-SiO2 nanoparticles over the surfaces of both fabrics after exhaustion procedures, regarding the concentration of colloidal paste and the type of material used, followed by a slight reduction of nanoparticles after twenty washing cycles. Moreover, the newly gained, good to very good UV protective functionality proved the suitability of the employed procedure and the sufficient durability of the selected coatings. Additionally, UV irradiation mainly caused damages to the cotton. Cotton/polyester became yellower under UV, although the application of TiO2-SiO2 protected the material against yellowness.

Three industrially-prepared (via the sulphate synthesis process) and commercially-available nanoTiO 2 colloidal suspensions were coated on polyester fabric using the conventional pad-dry-cure procedure, in order to enhance fabric functionalities by imparting self-cleaning and UV-protection ability. Various characterization techniques, i.e. transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), and UV/Vis spectroscopy of the suspensions revealed the presence of anatase TiO 2 spherical-shaped nanoparticles of different crystallite sizes, as well as its prominent absorption capacity within the UV region. Scanning electron microscopy (SEM) was adopted to analyse the morphological structure of nanoTiO 2 -modified PES fabrics. Furthermore, the photocatalytic activity was investigated through the discolourations of red wine and red beet stains under two types of light sources, i.e. direct day light and artificial UV light, by means of a spectrophotometry. The UV-protective properties were also evaluated by calculating the ultraviolet protective factors of individual coated fabric. The obtained results show acceptable blocking properties against UV-rays, as well as the adequate self-cleaning abilities of TiO 2 -modified PES fabrics as governed by the types and concentrations of applied TiO 2 suspension.

The presented case study examined the possibility of using four commercially available compact textiles in small-scale column purifying system conducted in a continuous-flow operation as filters for colour, organic pollutants and salt reduction. Two wastewaters were prepared for the experimental purposes by combining chemically different dyestuffs, auxiliaries and chemicals in order to simulate dye-bath effluents from cotton (reactive) and wool (acid) dyeing, respectively. Treatment of the laboratory-prepared wastewaters was carried out in columns packed with alternating layers of sand and individual compact textile and, for comparison, in a column comprised merely of sand. It was found that both non-woven textiles, either made from polypropylene (PP) or bicomponent PP/polyethylene (PE) yarn with more complex structure and higher total void area, were more suitable for adsorption/filtration of colour and organic pollutants from dye-rich textile wastewaters in comparison to both woven fabrics. Mon...

The main contribution of the research work presented here was to select and investigate a few commercially available textiles to study their filtration/adsorption potential for salt and total organic carbon (TOC) reduction during wastewater treatment. First, several physical–mechanical properties, such as tensile strength, thickness, weight, density and structural aspect of two woven (polyamide and polyester) and two nonwoven (polypropylene [PP] and PP/polyethylene [PE]) textiles, were determined. Also, the void amount and total void area percentage of textiles were measured, which influence the wastewater flow (clog) and filtration efficiency. With the intention of examining the adsorption ability of the selected textiles, kinetic experiments were carried out in shake-flasks using three commonly-used salts. Afterwards, small-scale column experiments were conducted in a continuous-flow operation to assess the TOC and salt reduction. It was found that both nonwoven textiles (either made from PP or...

In the research work presented here, a Plackett–Burman two-level partial factorial design was adopted as a multivariate strategy to determine the optimum UV/H2O2 process conditions for maximizing the treatment efficiency of dye-rich textile effluents. The influence of wastewater parameters, i.e. type and concentration of dye (C Dye), 100–300 mg/L; concentration of NaCl (C NaCl), 2.5–3.5 g/L; and concentration of urea (C Urea), 5–15 g/L; and the amount of NaOH (C NaOH), 1–2.4 mL/L; as well as the operational parameters, i.e. intensity of UV irradiation (I UV), 1.2–1.4 kW; the amount of H2O2 , 0.7–8.3 mL/L; and treatment time (t), 6–30 min; on the colour and the removal of organic pollutants was investigated. After determining seven variables, laboratory-scale experiments were conducted using two synthetically-prepared wastewaters solutions that were polluted with two structurally different reactive dyes and selected chemicals. The assessment of the UV/H2O2 pilot plant’s performance was by monitori...

Newly synthesized SiO 2 surface treated TiO 2 nanoparticles (TiO 2 –SiO 2 ) were prepared, characterized and utilized in functional dyeing as combined reactive dyeing of cotton fabrics. Factors affecting the dyeing and functional properties of the treated fabric, concentration of TiO 2 –SiO 2 and of reactive dye as well as dyeing regime were studied. The chemical and morphological structures of nano-upgraded cotton fabrics were characterized by ATR-FTIR spectroscopy and scanning electron microscopy. UV-blocking ability, coloration and comfortable behavior of cotton have been evaluated through ultraviolet protection factor, CIE L * a * b * color values and air permeability determinations, respectively. Incorporation of TiO 2 –SiO 2 into the dyeing with reactive dyes brought about an outstanding UV protection functionality of the dyed fabrics even after 15 laundering cycles with a negligible negative impact on color and comfortable properties. Improvement or decrement in the UV protection, comfort, and dyeing properties is governed by the reactant concentrations and the dyeing temperature.

Enzyme treatment technologies in textile processing have become commonly-applied techniques for the modification of fabric-handle appearance, and other surface and mechanical characteristics of fabrics. Most studies have focused on understanding the impact of enzyme treatments on the fabric preparation, dyeing, and finishing processes of woven fabrics, whilst only limited research has been reported regarding any enzymatic effects on the surface and handproperties of knitted fabrics. The aim of this study was to analyze the effects of two different enzymes Trichoderma reesei whole cellulase, and enriched (EGIII) endoglucanase cellulase, at three different enzyme dosages on 100 % cotton interlock knitted fabric. This was in order to evaluate certain surface properties such as pilling, friction. and geometrical roughness. Furthermore, the compression and tactile properties of knitted fabric were also analyzed. The results show that treatment conditions with enzyme Trichoderma reesei whole cellulase had the more pronounced effect on the surface properties compared to the enriched EGIII enzymes. In general, it can be concluded that both types of enzymes improved the surface properties and hand when compared with the silicone softener-treated reference sample of interlock knitted fabric, as is statistically confirmed by one-way analysis of variance.

The main contribution of the presented research is to examine the potential of natural zeolite for colour and TOC reduction when packed in a fixed-bed system, considering various parameters such as wastewater characteristics, properties of natural zeolite, loading rate and hydraulic retention time. Firstly, the diverse chemical aspects of tuff were determined using scanning electron microscopy and infrared spectroscopy with the intention of establishing the impact of tuff surface and chemical composition on its adsorption properties and decolouration possibilities. Secondly, a series of dynamic experiments were conducted on laboratory-prepared wastewaters combining chemically differ reactive dyestuffs, auxiliaries and chemicals in order to investigate biofilter’s treatment efficiency. Assessment of the biofilter’s performance was verified by monitoring absorbance and total organic carbon in initial and treated wastewaters. The results showed that when increasing the load from 22 to 37 mg/m3d (dyes) and fr...

The main contribution of the present work was to study the impact of Corona-treated wool fabrics’ induced surface properties on dye-bath exhaustion, in order to optimize different dyeing systems. Firstly, the differing chemical aspects of a woven wool fabric's surface were determined using two dissimilar analytical skills (XPS and polyelectrolyte titration). With the intention to establish the ability of low-temperature plasma treatment to change wool fibre morphology which could have an impact on sorption properties, fabrics were dyed with blue acid and blue metal-complex dyes, and dyeing behaviour were studied by means of on-line VIS spectrophotometry. Finally, dyed samples were colourimetricaly evaluated and colour differences calculated. The results provided evidence that the overall carbon C 1s content was decreased while oxygen and nitrogen atoms were increased when using ionized air for fabric modification. It has also been noted that the amount of positive-charged functional groups in various pH ranges are higher for Corona-treated wool fabric in comparison with the untreated that improves hydrophylicity and dyeing properties.

The main objective of this work was to compare the colour of different pretreated (alkaline, acidic and enzymatic) and dyed (conventional and ultrasonic-assisted) flax fibres, to establish the impact of various parameters on dyeing kinetics. Flax fibres were dyed using two direct dyes of different chemical structures and molecular mass. Diffusion profiles were established by the application of Fick’s Law and dyeing behaviour was studied by means of online spectrophotometry. Finally, the dyed samples were colorimetrically evaluated and colour differences and colour strengths were subsequently calculated. The results provided evidence that a dye molecule’s size has a greater influence on the exhaustion degree, migration and diffusion than individual pretreatment processes. The determined diffusion coefficients indicated superior dye mobility and faster diffusion into the fibres when ultrasonic power was used in comparison with conventional process. Nevertheless, the colour depth obtained was found to be low after ultrasonic dyeing using a larger dye molecule, implying part degradation of CI Direct Red 80 (and total degradation of small-size dyestuff, CI Direct Red 81).

A constructed wetland model, comprising two different substrate mixtures, was used to purify textile dyebath wastewater. Three laboratory prepared wastewaters containing three commercial dyes of different classes and chemical constitution (one vat and two reactive dyes), different chemicals (NaOH, NaCl) and auxiliaries (migration inhibitor, sequestering, defoaming and wetting agents) were employed. Purifying efficiency was verified by measuring pollution parameters, such as absorbance, pH, total organic carbon (TOC), chemical oxygen demand (COD) and electrical conductivity (EC). It was found that the constructed wetland model reduced dye concentration by up to 70%, lowered the TOC and COD values up to 88%, electrical conductivity up to 60% and pH from 12 to 7.6.

SUMMARY In this paper the effect of enzymatic bioscouring on the bleaching and dyeing of flax fibres was studied in comparison with conventional alkaline scouring. Enzymatic bioscouring was performed with a commercial multi-enzyme system consisting of pectinases, hemicellulases and cellulases. The enzyme and alkaline scoured flax fibres were subsequently oxidatively bleached with hydrogen peroxide and dyed with direct dye C.I. Direct Red 80 under the same conditions. The efficiency of both the scouring and bleaching processes was evaluated by weight loss and the whiteness of the bleached samples was determined according to CIE formula. The exhaustion profile of the used dye was followed on-line during the dyeing process using absorbance measurement. The colours of bleached and dyed samples were evaluated using CIELAB colour values. The residual pretreatment and dyeing baths were ecologically analysed with COD, TOC and BOD5. The obtained results indicate that enzymatic scouring provides a lower weight loss...

The purpose of this research was to investigate the influence of different pre-treatment processes, on the sorption properties of flax fibers and the impact of residual treatment baths on environmental pollution. Flax fibers were subjected to different scouring processes (alkaline, acidic and enzymatic scouring) and, subsequently, oxidative bleaching, with and without application of ultrasound energy. The sorption properties of differently pre-treated flax fibers were defined by iodine sorption value, moisture sorption, and water retention power. The residual pre-treatment baths were ecologically analyzed using total organic carbon, chemical oxygen demand, biochemical oxygen demand and biological degradability. The obtained results indicated that the alkaline, acidic and enzymatic scourings of flax fibers have a significant effect on their sorption properties and, consequently, on the bleaching process. The application of ultrasound in the scouring and bleaching bath increased the fiber weight loss and water retention power of the flax fibers, as well as improving the ecological parameters. The optimal pre-treatment process was enzymatic bioscouring because it provided a lower weight loss, a better absorptivity of the flax fibers, and is less environmentally harmful.

The sorption behavior of raw and treated flax fibers was investigated. This paper presents the effect of conventional pretreatment processes (alkaline, acid) in comparison to environmentally friendly enzymatic processes on the sorption ability of flax fibers. Weight-loss, moisture sorption, water retention value and contact angle were determined in order to interpret the pretreatment results. In addition, the influence of the process on the fibers' mechanical properties was studied. The ecological parameters of the treatment wastewaters were analyzed.

When wool dyeing with anionic dyes, "right-first-time" production and "batch-to-batch" color reproduction depend on the physicochemical properties of the wool fibers, the sorption properties of the dyes, and numerous technological parameters in the dyeing process. In this research, the effects of two process parameters (pH of dyebath and liquor-to-wool ratio) on dye sorption are investigated during batch dyeing of wool top and, consequently, with regard to color. Dyeing involves four anionic dyes—one acid dye (yellow) and three 1:2 metal-complex dyes (yellow, red, and blue). Dye sorption from unicomponent and bicomponent dyebaths is determined using on-line absorbance measurements, and the color of the dyed samples is evaluated colorimetrically using the CIELAB color system. The results indicate significant differences in the sorptions of the dyes with variations in dyebath pH and liquor ratio, which lead to color differences in wool production.

The presented study focuses on the development of a pad-dry-thermofix functional coating process using a mixture of microporous aluminosilicate particles in diverse bath formulations to impart UV-ray-blocking, thermal stability and easy-care properties to the cotton fabric. The results of Scanning Electron Microscopy (SEM) and X-ray powder Diffraction (XRD) revealed the presence of three different types of zeolites within the examined sample, i.e., the largest amount being zeolite A, followed by the zeolite X, and the zeolite ZSM-5. The surface characterization results of zeolite-coated/cross-linked textiles provided evidence of acceptable UV-ray-blocking properties and increased thermal stability, as well as enhanced tensile strength and breaking tenacity without considerably decreasing the whiteness degree. Moreover, the dry crease recovery angle increased for the cotton fabric cross-linked via an mDMDHEU, and decreased significantly using 30 g/L zeolites negatively influencing qualitative values. TG/DTA results have proven the enlarged thermal stability of aluminosilicate-coated cotton, although combustion was not prevented.

The objective of the presented research was to examine the potential of capillary electrophoresis (CE) for the analysis of structurally different reactive dyestuffs, their activation and posterior hydrolysis, with special focus on optimization of the working conditions. Preliminary, the effect of various additives to the background electrolyte on the resolution improvements versus migration time of Reactive Black 5 as a model dyestuff was investigated. Based on these results, the electropherograms of eight commercially interesting reactive dyestuffs of various chemical structures and their converted forms upon alkaline pH were carried-out. In order to examine the behavior of the reactive dyestuff during the dyeing process, the dye-bath absorbance was monitored throughout the Reactive Black 5 exhaustion, and the conversion of the dye's form was highlighted using the CE technique. The obtained results unequivocally prove that CE could offer a fast and efficient detection method of structurally different reactive dyestuffs, as well as their hydrolysis products in the dye-baths and effluents later on.