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1.
Effectiveness of two strongly basic anion exchange resins of the gel (Dowex PSR-2) and macroporous structure (Dowex PSR-3) was compared in order to remove three hazardous dyes such as C.I. Acid Orange 7 (AO7), C.I. Reactive Black 5 (RB5), and C.I. Direct Blue 71 (DB71) contained in water and textile wastewaters. Batch adsorption experiments were carried out to analyze the effect of phase contact time, initial dye concentration, and the presence of auxiliary materials (anionic and cationic surfactants, Na2CO3, and Na2SO4). The Langmuir model better described the adsorption process of the dyes onto both resins than the Freundlich model. The monolayer adsorption capacities (qe) of Dowex PSR-3 were calculated as 336.4 mg/g for AO7, 317.9 mg/g for RB5, and 150.4 mg/g for DB71 at 25°C. Dowex PSR-2 of the gel structure is characterized by considerably lower values of qe (50.1 mg/g for AO7, 17.2 mg/g for RB5, and 9.7 mg/g for DB71). Of special importance are high values of the working ion exchange capacities of Dowex PSR-3 determined from the breakthrough curves towards AO7 and RB5 equal to 127 and 85 mg/cm3, respectively. The pseudo second-order kinetic model described the experimental sorption data better than the pseudo first-order model. Methanol addition to the 1 M HCl and 1 M NaOH solutions improved the effectiveness of dye desorption.  相似文献   

2.
The effect of pH and temperature on the dye sorption of wool powders   总被引:1,自引:0,他引:1  
The sorption behavior of wool powders for three acid dyes (C. I. Acid Red 88, C. I. Acid Red 13 and C. I. Acid Red 18) and a basic dye (methylene blue) was investigated as a function of pH and temperature. The sorption capacity of wool powders depends on the pH of dye solution. The maximum uptake of acid dyes and methylene blue by wool powders occurred at pH 2.5 and pH 7.5, respectively. The effect of pH on the sorption of the hydrophilic dyes (C. I. Acid Red 13 and C. I. Acid Red 18) was more significant than that of the uptake of the hydrophobic dye (C. I. Acid Red 88). Increasing temperature enhanced the dye sorption ability of coarse wool powders, but did not impact that of fine wool powders. The dye‐absorption models of wool powders agree with the Langmuir isotherm. Comparison to activated charcoal and other sorbents indicates that fine wool powders have excellent dye sorption capacity even at room temperature, and may be used as a potential sorbent. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

3.
A simple method was developed for the determination of the dyes Solvent Blue 14 (SB-14), Solvent Orange 7 (SO-7) and Solvent Red 24 (SR-24), based on high-performance liquid chromatography (HPLC) coupled with UV-Vis detection. The dyes were separated employing a reverse phase C-18 column, with gradient elution using a mobile phase containing acetonitrile/water. In conjunction with suitable sample pre-treatment protocols, the method was applied to the quantification of the dyes in gasoline samples.  相似文献   

4.
The solubility parameters of polylactide (PLA), poly(ethylene terephthalate) (PET), and various disperse dyes calculated according to the group contribution method were used to explain the low sorption of some disperse dyes on PLA but the high sorption of the same dyes on PET. It was found that the dyes with high sorption on PLA tended to have solubility parameters near that of PLA, which has a lower solubility parameter than that of PET. It was also found that the solubility parameter, which was calculated based on cohesive energy and molar volume at 25°C, was more appropriate for explaining dyeings at lower temperature, 100 and 110°C, than those at higher temperature, 130°C. Based on the finding that dyes with solubility parameters near that of PLA tend to have high sorption on PLA, general structures for disperse dye that may have high sorption on PLA were proposed. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 416–422, 2005  相似文献   

5.
An ion exchanger with carboxyl groups as active sites was prepared by activating sawdust with epichlorohydrin, followed by coupling the epoxy-activated sawdust with aspartic acid. The optimal sorption condition, sorption capacity, kinetics and thermodynamics of basic dyes on sawdust ion exchanger (SIE) from aqueous solution were investigated in a batch system. Two basic dyes, methylene blue (MB) and crystal violet (CV), were selected as sorbates. The optimal pH value of MB and CV solutions for favorable sorption was pH 4 and above. The removal ratios of MB and CV on SIE increased with increasing sorbent dose but decreased with increasing dye concentration. The isothermal data of MB and CV sorbed on SIE correlated basically with the Langmuir model. The maximum sorption capacity (Q m ) of SIE for MB and CV was 222.22 and 232.56 mg/g, respectively. The sorption equilibriums of MB and CV on SIE were reached at about 9 h, and the sorption processes could be described by the pseudo-second-order kinetic model. The thermodynamic study indicated that the sorptions of MB and CV on SIE were spontaneous and endothermic at the predetermined temperatures. High temperatures were favorable for the sorption processes.  相似文献   

6.
A modified Donnan model has been derived, based on hydrophobic and ionic interactions between dyes and fibres. This model gives a good prediction of a cationic dye equilibrium sorption on an acrylic fibre under different dyeing conditions. The decrease in dye sorption with increasing salt concentration, followed by an increase in the dye sorption following further increase in the concentration of some salts (such as sulphates and phosphates), can be interpreted by this model. The study provides a quantitative approach to the dual functions of simple electrolytes during cationic dyeing, i.e. the competition of sorption sites with dyes through ionic interactions and the promotion of the dye sorption through hydrophobic interactions.  相似文献   

7.
季铵型阳离子聚丙烯酰胺的无盐染色行为   总被引:2,自引:2,他引:0  
以季铵型阳离子聚丙烯酰胺作为一种新的阳离子助剂对棉纤维进行处理,应用于活性染料无盐染色,对染色过程中染料与处理后棉纤维之间的吸附类型、吸附热力学及吸附动力学进行了研究。结果表明,无盐染色过程符合Langmuir吸附模型;吸附过程是放热自发进行的,低温有利于染料的吸附;吸附动力学符合二级动力学模型,属于化学吸附过程。与传统有盐染色结果相比,染色后的阳离子化棉纤维色深增加,染料利用率提高。  相似文献   

8.
The removal of two anionic dyes, C.I. Acid Orange 7 (AO7) and C.I. Acid Red 17 (AR17), by ultrasound-assisted adsorption on the modified nanoclay in aqueous solutions was studied. The modified nanoclay was characterized by SEM/EDX, BET, XRD and FT-IR techniques. The average crystal size for the interlayer spacing of the modified nanoclay was about 14.3 nm. Central composite design (CCD) was used for the optimization of the operational parameters, including the initial dye concentration, sonication time, adsorbent dosage and temperature. The results demonstrated a good agreement between the predicted values obtained by the model and the experimental values for both AO7 (R2= 0.959) and AR17 (R2=0.971).  相似文献   

9.
Hydrophilic dyes, reactive brilliant red K‐2BP (C.I. Reactive red 24), acid fuchsin (C.I. Acid violet 19), and cationic brilliant red 5GN (C.I. Basic red 14), have been encapsulated into hydrophobic polystyrene (PS) latex particles using double miniemulsion technique. In this method, the water droplets containing dyes were first suspended in octane/styrene phase using lipophilic emulsifiers to form a primary miniemulsion. This miniemulsion was further dispersed in water and miniemulsified, followed by polymerization at high temperature to form dye/PS core‐shell colorants. Experimental results show that this technique can cause as high as 80% of encapsulation efficiency for all three dyes, and obviously improve the water‐proofing property and photostability of organic dyes. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

10.
The sorption behavior of acid dyes onto cetyltrimethylammonium bromide (CTAB)- modified silica as a function of pH in the aqueous medium was studied. Single- and multi-solute sorption equilibria of orange Ⅱ(OR), phenol red (PR) and Eriochrome Black T (EBT) were studied at pH 3, unbuffered water pH and pH 11. Sorption behavior of EBT could not be conducted at pH 3 due to its aggregation in acidic medium. All the reaction conditions, experimental protocols and techniques remained the same throughout the sorption process. Sorption isotherms for single-solute system were fitted by the Langmuir model, while Langmuir competitive model (LCM) and the ideal adsorbed solution theory (IAST) coupled with Langmuir model (IAST/Langmuir) were used for the prediction of multisolute competitive sorption. Sorption affinities influenced by the factors like physical interactive forces between the molecules of CTA on silica and sorbate, structural limitations of the dyes based on their geometrical arrangement were investiga  相似文献   

11.
The Amberlite IRA-900 resin was tested to remove C.I. Reactive Black 5, C.I. Reactive Red 2 and C.I. Reactive Red 120 dyes from solutions. Batch adsorption studies concerning effects of the phase contact time, pH, temperature, the presence of salts and surfactants were run. A pseudo second-order kinetic model was used to evaluate the rate constants. The Langmuir equation provided good fit for the experimental data of the equilibrium adsorption. The studies of dyes uptake using the dynamic method were run. The treatment efficiency of Amberlite IRA-900 to model wastewaters was tested. Desorption experiments by the batch method were performed.  相似文献   

12.
The instability in water of poly(vinyl alcohol) (PVA)/poly(carboxymethyl cellulose) (CMC) was improved through radiation-induced grafting with a styrene monomer. The PVA/CMC blend graft copolymer was used as a sorbent for dye wastes normally released from textile factories. The factors that may affect the sorption process such as time, temperature, weight of the blend graft copolymer, and volume of the dye waste were investigated. The sorption of dyestuffs by the blend graft copolymer was determined by a method based on spectroscopic analysis. The results showed that the blend graft copolymer has a high affinity for basic, acid, and reactive dyes. Meanwhile, it was observed that the sorption of dyes is more effective at the high temperature of 70oC. Moreover, it was found that the sorption of dyes depends on the weight of the blend graft copolymer and does not depend on the volume of the waste solution. The sorption of the dyestuffs by a PVA/CMC graft copolymer may be considered to be a practical method to remove organic pollutants. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 136–142, 2001  相似文献   

13.
Chrysophenine G (C.I. Direct Yellow 12), Benzopurpurine 4B (Red 2), Sirius Red 4B (Red 81), Sirius Supra Blue BRR (Blue 71) and Sky Blue 6B (Blue 1) were selected as typical direct dyes, and the equilibrium adsorptions on cellulose (Cellophane) from the 1:1 and 2:1 molar mixture dye baths were investigated at 90° and 70°C. The standard affinity in mixture dyeing was obtained by the equation derived from the assumption of monodispersed and diffusive adsorption. The standard affinity in mixture dyeing was nearly equal to that in single dyeing, except for the Chrysophenine G–Sky Blue 6B system. However, judging from the fiber and solution log sum plots, there was a definite difference between mixture and single dyeing. It was explained by the change of activity of dye and sodium ions on substrate followed by the marked change of the total adsorption. The adsorption behavior of direct dyes is discussed in detail from the viewpoint of concentration dependence of the activity coefficient of dye and sodium ions on the substrate.  相似文献   

14.
The kinetics of sorption of three basic dyes, namely, Chrysoidine (BO2), Astrazon Blue (BB3) and Astrazone Blue (BB69) onto sphagnum moss peat have been investigated. The study focuses on the application of three sorption kinetic models for predicting the uptake of basic dyes. The sorption behaviour is found to be second order, based on the assumption of a pseudo-second order mechanism. The rate constant of sorption, the equilibrium capacity and initial sorption rate with the effect of various peat doses and initial dye concentrations have also been predicted.  相似文献   

15.
The capacity of poly(vinyl alcohol) (PVA) to crosslink through freeze/thaw method was used to obtain PVA hydrogel membranes (HG) that were subjected to sorption and diffusion experiments using three dyes: Congo red (CR), methylthymol blue (MTB), and crystal violet (CV). To study the sorption of dyes into the cryogenic membrane, dye solutions at different concentrations were used. After sorption, desorption of dyes from the PVA membrane was monitored to quantify the possible regeneration of the membrane (PVA HG). To have a deep insight on the mechanism behind the desorption process, dye‐release kinetics were studied. The diffusion experiments reveal the fact that CR and MTB do not permeate the PVA HG membrane making it a promising candidate in the advanced purification processes of wastewaters. The effect of the incorporation of dyes (CV, CR, and MTB) on the chemical properties of PVA cryogel matrices has been studied by using several techniques such as: differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

16.
酸性染料在纺织用甲壳胺纤维上的吸附   总被引:9,自引:0,他引:9  
运用三种吸附理论模型,即Langmuir、Freundlich和Redlich-Peterson吸附模型、讨论了酸性染料在纺织用甲壳胺纤维上的吸附机理,并研究了染色温度对吸附参数的影响和硫酸钠在染色中的作用研究结果表明,Langmuir和Redlich-Peterson模型均能很好地描述酸性染料在甲壳胺纤维上的吸附性质,酸性染料以离子键的形式在甲壳胺纤维上发生吸附;酸性橙11在甲壳胺纤维上的吸附是典型的放热过程,Langmuir吸附常数KL随着染色温度的升高而降低,染浴中加入硫酸钠导致了酸性染料吸附量的降低,这意味着硫酸钠在染色中将起缓染作用  相似文献   

17.
《分离科学与技术》2012,47(15):2351-2360
ABSTRACT

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.  相似文献   

18.
C. I. Disperse Red 60 (DR60) was absorbed into polymer films and textile fibers in the presence of supercritical carbon dioxide at pressures between 5 and 33MPa and at temperatures between 308.2 and 423.2 K. Polystyrene (PS) and poly(methyl methacrylate) (PMMA) films and polyester (polyethylene terephthalate: PET) and Nylon 6 textiles were used as absorbents. The amount of equilibrium sorption of dye increased both with pressure and temperature. The sorption behavior was successfully analyzed with the quasi dual-mode sorption model.  相似文献   

19.
Scallop shell was used as a low-cost adsorbent for removal of two anionic textile dyes, Reactive Blue 19 (RB19) and Acid Cyanine 5 R (AC5R), from aqueous solutions. The adsorbent was characterized using inductively coupled plasma optical emission spectrometry (ICP-OES), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The dye removal efficiency of scallop shell was determined as function of contact time, solution pH, initial dye concentration and adsorbent dosage. With increasing dye concentration, the adsorption of both dyes decreased, while it increased with increasing adsorbent dosage. Optimum removal of RB19 and AC5R was achieved at pH=6. Adsorption equilibrium data were well described by the Freundlich model. The maximum dye adsorption capacity of scallop shell as estimated from the Langmuir isotherm was 12.36 and 12.47 mg/g for RB19 and AC5R, respectively. The adsorption kinetic data showed excellent correlation with the pseudosecond-order model. It was concluded that scallop shell has a remarkable potential for the sorption of RB19 and AC5R and can be used for treatment of the dye contaminated wastewater.  相似文献   

20.
A series of phenylazopyrazolone disperse dyes containing an acylamide moiety were synthesised from carboxyl‐containing acid dyes via chlorination and amidation with different sorts of amines. The structures of these new dyes were confirmed by Fourier Transform–infrared, proton nuclear magnetic resonance, mass spectroscopy and elemental analysis. Their solvatochromic properties in different solvents were also investigated and the absorbance spectra of the acylamide dyes in solution exhibited a red shift when dissolved in dimethylformamide, compared with acetone. Their dyeing behaviour, including dye sorption, colour build‐up and colour fastness properties on poly(lactic acid) fibres, was also determined, whereupon it was found that the tertiary acylamide dyes simultaneously exhibited high dye sorption and satisfactory colour build‐up and fastness properties on the poly(lactic acid) fabric.  相似文献   

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