• Membrane and Water Treatment
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• v.3 no.4
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• pp.243-252
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• 2012

Tri-n-butyl phosphate (TBP) was used as carrier for the transport of Golden yellow and Cibacron LSG dyes through a hexane bulk liquid membrane. The transport efficiency of dyes by TBP was investigated under various experimental conditions such as pH of the feed phase (dyes solution), concentration of the receiving phase (NaOH solution), concentration of TBP in membrane, rate of stirring, effect of transport time, type of solvent, dye concentration in feed phase, effect of temperature.. The maximum transport dyes occurs at ratio of 1:1 TBP-hexane At pH 3.0 0.1 (feed phase) the transport dyes decreased. At high stirring speed (300 rpm) the dyes transport from the feed phase to the strip phase was completed within 60 minutes at $27^{\circ}C$. Under optimum conditions: Feed phase 100 mg/L dyes solution at pH 1.0 0.1, receiving phase 0.1 mol/L NaOH solution, membrane phase 1:1 TBP-hexane , Stirring speed 300 rpm and temperature $27^{\circ}C$, the proposed liquid membrane was applied to recover the textile effluent.

• Journal of Environmental Science International
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• v.8 no.2
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• pp.241-248
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• 1999

The photocatalytic decolorization and photodegradation of wastewater contamininated with dyes such as methyleneblue tetrahydrate(MBT), methyl orange(MO), phenol red(PR) and the mixed dyes have been studied using a batch reactor in the presence of aerotropic and titania. Degussa P25 titanium oxide was used as the photocatalyst and proved to be effective for the dyes-degradation when irradiated with UV-light source emitting the wavelength of 253.7 nm in the presence of air. In addition to removing the color from the wastewater, the photocatalytic reaction simultaneously reduced the COD and optical density which suggests that the dissolved organic compounds have been photooxidized. The reaction rate of disappearance of the dyes were measured as a function of the irradiation times. The photooxidative procedure of the aquatic solution have the first order reaction-kinetics. The rate constants were increased in the order of PR < MBT < $gL^{-1}-TiO_2$ powder were irradiated with the UV -light source.

• Membrane and Water Treatment
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• v.8 no.3
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• pp.259-277
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• 2017

Adsorption is a widely used technique for the removal of dyes from wastewaters by variety of adsorbents. In this work, the main focus is on the potential assessment of anion exchange membrane for the removal of different dyes using batch system and investigation of experimental data by applying various kinetic and thermodynamic models. The removal of anionic dyes i.e., Eosin-B, Eriochrome Black-T and Congo Red by anion exchange membrane BII from aqueous solution was carried out and effect of various parameters such as contact time, membrane dosage, temperature and ionic strength on the percentage removal of anionic dyes was studied. The experimental data was assessed by kinetic models namely pseudo-first-order, pseudo-second-order, Elovich liquid film diffusion, Bangham and the modified Freundlich models equation have been used to analyze the experimental data. These results indicate that the adsorption of these anionic dyes on BII follows pseudo-second-order kinetics with maximum values of regression coefficient (0.992-0.998) for all the systems. The adsorption of dyes was more suitable to be controlled by a liquid film diffusion mechanism. The adsorptive removal of dye Eosin-B and Eriochrome Black-T were decreased with temperature and thermodynamic parameters such as free energy (${\Delta}G^o$), enthalpy (${\Delta}H^o$) and entropy (${\Delta}S^o$) for adsorption of dyes on membrane BII were calculated at 298 K, 308 K and 318 K. The values of enthalpy and entropy were negative for EB and EBT representing that the adsorption of these dyes on BII is physiosorptive and exothermic in nature. Whereas the positive values of enthalpy and entropy for CR adsorption on BII, indicating that its adsorption is endothermic and spontaneous in nature. It is evident from this study that anion exchange membrane has shown good potential for the removal of dyes from aqueous solution and it can be used as adsorbent for dues removal on commercial levels.

• Journal of Fashion Business
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• v.11 no.2
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• pp.102-112
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• 2007

Effect of the pH condition was examined on extraction and dyeing of the yellow and red dyes of safflower. Absorption of dye solution extracted from safflower was changed by pH of solvent. In the case of yellow dyes, cotton and ramie weren't dyed regardless of pH of dye bath, but silks were significantly dyed at pH4. Raw silk showed better dyeability than refined silk. In the case of red dyes, cotton and ramie absorbed red dyes selectively, but silks absorbed yellow dyes more significantly than red dyes. Efficiency of extraction and dyeing of yellow dyes in acidic range were find out higher than that in neutral range. Red dyes was effectively extracted at pH11 and dyed at pH6.

• Textile Coloration and Finishing
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• v.7 no.3
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• pp.1-10
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• 1995

The optical behavior of coloring matter extracted from onion's coats, the depression effects of destruction, yellowing and W transmittance of silk treated with color solution of onion's coats color difference of silk fabrics dyed with acid dyes and drycleaning fastness of silk treated with color solution has been investigated. The results are as follows : 1) The coloring matter extracted from onion's coats by alkali-acid method appeared properties of aglycon type. 2) &{\lambda}_{max}&of color solution extracted by distilled water was found at 280 and 327nm. 3) The decrease of tensile strength and the elongation of the silk treated with color solution were depressed but those of untreated silk were increased by irradiation of UV light. 4) The yellowness index of silk treated with color solution showed a little change by irradiation. 5) The UV transmittance of silk treated with color solution was decreased as increasing concentration of color solution. 6) The color difference after dyeing with several acid dyes on treated and untreated silk fabrics showed remarkable changes. 7) Drycleaning fastness of silk treated by color solution was excellent.

• Textile Coloration and Finishing
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• v.14 no.3
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• pp.26-33
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• 2002

Dyeing properties and crosslinking effect of bifunctional reactive dyes on chitosan fiber were investigated to improve the stability of chitosan fiber against the mild acidic solution and the wet processing. Chitosan fibers were crosslinked with epichlorohydrin for comparing purpose, and dyed with C. I. Reactive Red 194, C. I. Reactive Blue 50, and the reactive dye having two $\alpha$-bromoacrylamide groups at various concentrations. The initial dyeing rates of reactive dyes are rapid and chitosan fibers absorb the relatively large amount of dyes. The chitosan fibers dyed with these dyes show the low degree of swelling and the low solubility in 1 % acetic acid solution and also represent the higher thermal stability The reactive dye with two $\alpha$-bromoacrylamide groups shows higher crosslinking effect than other dyes.

• Textile Coloration and Finishing
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• v.5 no.2
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• pp.91-98
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• 1993

The silk fabrics were treated with color solution extracted from leaf of Camellia. The depression effect of destruction and yellowing of silk treated with color solution, shift of UV-VIS spectra of color solution, color difference of silk fabrics by dyeing with acid dyes and drycleaning fastness of silk treated with color solution were studied. UV-VIS spectra appeared to hypsochromic shift by irradiation. The decrease of tensile strength and the elongation of the silk treated with color solution showed depressed but those of untreated silk increased by irradiation. The yellowness index of silk treated with color solution showed a little change by irradiation. The color difference after dyeing with several acid dyes on treated and untreated silk showed not remarkable changes. Dsrycleaning fastness of silk treated by color solution was excellent.

• Textile Coloration and Finishing
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• v.15 no.5
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• pp.285-293
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• 2003

Waterborne PU membrane was prepared from waterborne PU dispersion solution to investigate physical and staining properties. The staining properties of waterborne PU membrane with acid dyes and disperse dyes were observed. The physical properties of the PU membrane were investigated by X-ray diffraction and IR spectroscopy. The staining property of waterborne PU membrane for azo acid dyes is better than that of disperse dyes. X-ray diffraction peaks sharpened and tensile strain and stress increased with heat setting temperature.

• Textile Coloration and Finishing
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• v.24 no.3
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• pp.165-172
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• 2012

The stability of yellow and red dyes prepared from safflower (Carthamus tinctorius L.) in aqueous solution and in solid state was investigated. External factors such as light irradiation and temperature on the stability were examined during storage. Changes in absorbance of dye solutions and the color changes of fabrics dyed after long time storage were measured. Also, color reproducibility during storage was investigated by dyeing test on various fabrics. Red colorant in aqueous solution was very unstable to light, resulting that about 40% of absorbance were lost in 12hrs. The absorbance of yellow dye solutions was not decreased within 84hrs. In aqueous medium, yellow dye was much more stable than carthamin. Both dyes are relatively stable for long storage when they are stored in solid state compared to when in aqueous solution. Color changes are marginal in both dyes.

• Fashion & Textile Research Journal
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• v.7 no.3
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• pp.339-345
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• 2005

It is difficult to dye nylon/viscose rayon mixture fabrics by one-bath one-step dyeing method, because acid dyes and reactive dyes require acidic dyebath for adsorption and alkaline dyebath for fixation respectively. In order to overcome the disadvantage of the conventional two bath two step dyeing method of nylon/viscose rayon mixture fabric, it was pretreated with cationizing agent containing chlorohydrine group in aqueous solution of sodium hydroxide. The pretreated nylon/viscose rayon mixture fabrics produced cationized fabrics that could be dyed with acid dyes and reactive dyes under neutral condition. This study was carried out to investigate dyeing possibilities, surface reflectance spectra and color characteristics of cationized nylon/viscose rayon mixture fabrics with acid dyes and reactive dyes in a non-electrolytic and neutral dyebath by one bath one step dyeing method.