The study of direct dye sorption on flax fibers during dyeing (original) (raw)

Basic Dye Removal with Sorption onto Low-Cost Natural Textile Fibers

Processes, 2018

Over the last several years, the trend of researchers has been to use some very low-cost materials as adsorbents. For this purpose, some already commercially used bast fibers were selected as potential adsorbent materials to remove basic dye from synthetic effluents. The adsorption of basic yellow 37 dye was studied using three different bast fibers under the names of flax, ramie, and kenaf. Their morphological structure was examined using several techniques such as scanning electron microscopy (SEM), crystallinity, X-Ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), as well as those characterizations being a useful tool to propose a mechanism of the whole adsorption process. The adsorption evaluation was achieved by studying at first the pH (12) and temperature effects (25–55 °C). Two isotherm models (Langmuir and Freundlich) were also applied to the experimental equilibrium data revealing the superiority of ramie fibers (327, 435, and 460 mg·g−1 (25 °C) for...

Sorption of acid violet 17 and direct red 80 dyes on cotton fiber from aqueous solutions

Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2007

Sorption of acid violet 17 and direct red 80 azo dyes on locally available cotton fiber from aqueous solution has been investigated as a function of shaking time, pH, dyes concentration and temperature. Maximum sorption of acid violet 17 and direct red 80 on cotton fiber was achieved within 30 and 60 min of shaking time and at pH 8 and 8.5, respectively. Sorption isotherms for acid violet 17 and direct red 80 dyes were obtained at pH 8 and 8.5, respectively, at constant temperature. These isotherms are L-3 types having small plateaus, and the upward trends in sorption capacity after the plateaus points towards the possibility of multilayer formation. The increasing temperature induces a negative effect on the sorption of acid violet 17 (exothermic) and positive effect on the sorption of directs red 80 (endothermic). Isosteric heat of adsorption (q st ) have also been calculated at different surface coverage indicating that cotton fiber possessed heterogeneous surface with site of different activity. The results also indicate that initial sorption, whether chemical or physical means, occurs first on the most active sites and then on the sites of lesser activity.

Kinetic considerations of textile dyes adsorption from water on a sorbent from cellulosic waste

Studia Universitatis Babeș-Bolyai Chemia

The synthesis of a new sorbent based on waste cotton cellulose and kinetics of adsorption of reactive textile dye from aqueous solution are the subject of the study in this manuscript. The sorbent is made of waste cotton fibbers collected from the textile plants for spinning yarn and weaving fabrics after being physically and chemically modified. Qualitative and quantitative characterization of the sorbent shows that carbon is dominant in the chemical composition. The sorbent used is a relatively finely divided material with heterogeneous porous particles, generally below 300 µm in size. Maximum adsorption capacity and the rate constant of the pseudo-second order generally depend on the amount of the cellulose-based sorbent, the initial dye concentration and the temperature. A new kinetic model based on the results of adsorption capacity and pseudo second order rate constant was defined. The low value of the activation energy means that the adsorption is mostly of a physical nature. Thermodynamic parameters, change of free Gibb's energy, change of enthalpy and change of entropy, as well as activation energy according to the standard equation confirm the adequacy of the new kinetic model of dye adsorption.

8 Physico-chemical Aspects of Wool Dyeing: Adsorption, Kinetics and Thermodynamics

industrial sectors in terms of environmental protection levels, comfort, and health. In order to manipulate the process of natural dyeing efficiently and to get maximum color yield in economical way, it is essential to develop knowledge based on dye chemistry, various aspects of dyeing process variables, rate of dyeing and chemical kinetics of dyeing for different dyes and fiber combinations. In this chapter, physical and chemical aspects of wool dyeing processes were discussed with the focus on the effect of chemical modifications of textile materials on the adsorption characteristics. A comparative analysis of various textile substrate surfaces were discussed in relevance to the dyeing process parameters responsible for dye stickiness towards textile materials.

Dyes adsorption on functionalized fibrous materials

2011

Wastewater effluents from textile industry mainly contain dyes used in the dyeing or printing of textiles yarns or fabrics. A lot of technologies can be adopted for dye removal from wastewaters, among others biological treatments based on active mud, active carbon adsorption or membrane process. Nevertheless none of these methods is performing towards all classes of dyes; treatment plants of great dimensions and difficult handling can be required, while cost of adsorbent materials can be prohibitive. This research work focuses on dye adsorption, choosing as absorbers low cost fibrous materials, mainly cellulose based, submitted to a cationization process using a quaternary ammonium compound like 3-chloro-2-hydroxypropyltrimethylammonium chloride. This cationic functionalization has been tested toward anionic dyes such as acid, direct, reactive and cationic dyes. Treated materials were characterized by FTIR-ATR spectroscopy while the treatment efficiency was investigated through exhaustion and kinetic adsorption tests. Comparisons were carried out between treated and untreated samples, showing the cationization effect, and with activated carbon. Best results were obtained with cationized cotton, both in linters or "tulle" fabric form, showing good performance towards all the investigated dyes. These materials were chosen to prepare a prototype of filter that was tested in continuous. Even in this case the good behavior of our material was confirmed, underlined in particular by the comparison with active carbon. In fact, for example, 26 g of treated cotton fabric were able to filter 13 L of 0.25 g/L reactive dye solution before obtaining 5 % of original concentration of the dye in filtered water, with no pressure drop and homogeneous filter exhaustion. Finally, regeneration tests by bleaching were carried out and it was found that regenerated material maintained good adsorption power. It can be concluded that cationization is a valid method to produce a competitive dye adsorbent material with great efficiency towards many dye classes and with a good behavior if used in continuous wastewater filtration.

Adsorption of Textile Dyes Using Agave Americana (L.) Fibres: Equilibrium and Kinetics Modelling

Adsorption Science & Technology, 2007

This study was carried out to examine the potential of Agave americana fibres (AAF) for the treatment of wastewater contaminated with dyes. The batch mode adsorption of two dyes, viz. Sumfixe Supra Red (SSR) and Alpacelle Lumiere Brown (ALB), by AAF was investigated at different pH values, temperatures and initial dye concentrations. The highest dye adsorption capacities at 30°C were attained at pH 2.0 for SSR and at pH 2.5 for ALB. In both cases, an increase in temperature increased the velocity of the reaction. The maximum amounts of dyes desorbed were at basic pH values. To compare our results with studies on other biomaterials, the adsorption isotherms and kinetic data were analysed employing the usual models (Freundlich, Langmuir and Temkin isotherms and first- and second-order kinetics). Conventional analysis indicated that the kinetics of the processes were closer to pseudo-second order rather than first order. The data were also modelled with a new method of analysis based o...

Removal of Directs Dyes from Wastewater by Cotton Fiber Waste

International Journal of Waste Resources, 2018

Environment protection is a precondition for sustained growth and a better quality of life for all peoples on earth. Aqueous industrial effluents are the main sources of pollution. Among the compounds of these effluents, dyes are particularly resistant to discoloration by conventional methods, and discharges present many problems that must be supported. Synthetic dyes are used in industrials sectors; especially in the textile, industry. There is a certain selectivity of raw cotton fibers for the different types of dyes, depending on the chemical structure of the dyes. We note that this affinity is very high for direct dyes and decreases for reactive dyes and pigment dyes. This study focuses on the elimination of direct dyes wastewater from the textile industry, by their adsorption on waste very adsorbent cotton fibers, the removal rate greater than 75% for the three types of direct dyes used, a mathematical of the adsorption isotherms of and their kinetics of adsorption was made and...

Numerical study of the adsorption of dyes from textile effluents

Applied Mathematical Modelling, 2008

The textile industry is one of the greatest generators of liquid effluents, due to the high quantities of water used in the dyeing process. Fixed bed adsorption columns using activated carbon have been widely used in industrial processes for the removal of contaminants from textile effluents. In this study we present the modelling of an adsorption process applied to textile dyes, using fixed bed columns. This model permits the prediction of the dye concentration at the adsorption column outlet, considering the influence of various operational parameters. The adsorption isotherms of the dye Basic Green 4, over granular activated carbon at 25°C in an aqueous solution, were determined experimentally through a comprehensive series of tests. The Langmuir and Radke-Prausnitz models gave the best results for the adsorption isotherms. Tests were carried out in fixed bed columns to determine the breakthrough curves, with variations in feed rate, feed concentration, diameter of the column and mass transfer coefficient. The experimental conditions were simulated using a transient mathematical model. The data obtained numerically and experimentally were compared to validate the mathematical model proposed.

Removal of Reactive Dyes From Aqueous Solution by Adsorption onto Alfa Fibers powder

The absorbent Alfa fibers powder was used for its low cost, available and natural for removal of reactive textile dyes (reactive red 23 (RR-23) and reactive blue 19 (RB-19)) from aqueous solution. The absorbent Alfa fibers powder was obtained from leaf of Stippa Tenacissima L crushed and screened with a particle size less than < 2mm. Batch experiments were carried out for sorption kinetics and isotherms. Operating variables studied were pH, treatment time, temperature, dye and adsorbent concentrations. The adsorption parameters were determined based on Langmuir and Freundlich isotherm models. These parameters were obtained from the equilibrium adsorption data for the two reactive dyes. While the kinetics and thermodynamic parameters were used to establish the adsorption mechanism. As an adsorbent, Alfa fibers powder have a preference for Reactive Red 23, retaining up to 34.13 mg/g at 22°C, whereas a retention of only 11.33 mg/g at 22°C has been achieved by Reactive blue 19. Besides that, the thermodynamic study showed that the dye adsorption onto absorbent Alfa fibers powder was favourable, endothermic and spontaneous.