• Textile Coloration and Finishing
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• v.5 no.3
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• pp.182-187
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• 1993

The binding isotherms of Methylene Blue with Poly(vinyl pyrrolidone) (PVP) were determined in a Mcllvaine buffer of pH 8.0 at 3$0^{\circ}C$ by a dynamic dialysis methods. The isotherms showed a partition binding which was increase linearly with the increase of free dye concentration in solution. The Scatchard plots for Poly(vinyl pyrrolidone)-Methylene Blue gave a constant value. The results were interpreted by the McGhee and von Hippel theory considering non-cooperative binding. The intrinsic binding constant k, for Poly(vinyl pyrrolidone)-Methylene Blue was 6.02$\ell$/base mol.

• Journal of the Korean Ceramic Society
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• v.11 no.2
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• pp.11-16
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• 1974

Korean Yung-il bentonite was treated with potassium chloride, zinc chloride, calcium chloride, ferric chloride, or chromic chloride solutions respectively varying their concentration, treating temperature and treating time. The adsorbabilities of methylene blue on these pretreated bentonite were investigated. In the case of treatment with potassium chloride solution, the improvement of the adsorbahility of methylene blue on the products was observed, and in the best result the adsorbability was 1.6 times better than that on the original bentonite. With zinc chloride solution, the optimum adsorbability was a value of 1.7 times better than that on the original bentonite. With ferric chloride, chromic chloride or calcium chloride solution, slight improvement of the adsorbability was observed.

• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.366-371
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• 2005

In this study treatment efficiencies of methylene blue were evaluated in term of BOD, COD, TOC, absorbance and initial decolorization rates. Ozonation of the dye in distilled water was performed in a laboratory scale cylindrical batch reactor. The decolorization process of methylene blue was carried out by bubbling ozone at the bottom of a bubble column reactor containing the dye solution. Decolorization, determined by measuring the light absorbance at the maximum wavelength in the (${\lambda}_{max}$, 660 nm), was almost complete after 40 min with an ozone concentration of $50{\pm}10mg/L$. The $TOC/TOC_0$ ratio after ozonation was about 83.8%, the COD was diminished to 44.0% of the initial value. The $BOD_5/COD$ ratio was increased from 64.2% to about 90.8%, indicating an enhancement of biodegradable compounds in the ozonated solutions. The pseudo first-order rate constants of the ozonation was $3.30{\times}10^{-2}min^{-1}$ and the activation energy was $3.01kcal{\cdot}mol^{-1}$ at $30^{\circ}C$.

• Korean Chemical Engineering Research
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• v.61 no.2
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• pp.273-277
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• 2023

The biosorption of methylene blue (MB) from aqueous solution was investigated using dried Rhodotorula glutinis as the biosorbent. The effects of pH, initial dye concentration, biosorbent dosage, and kinetic studies were determined to obtain valuable information for biosorption. Results indicated that most of the adsorbed MB bound within 30 minutes of contact and the MB adsorption capacity increased from 21.1 to 101.8 mg/g with the initial MB concentration increased from 50 to 300 mg/L. Additionally, the MB adsorption capacity gradually increased from pH 4.0 to 9.0, reaching its peak at an initial pH of 9.0. As the biomass load was increased from 0.25 to 4.0 g/L, the MB removal efficiency increased from 14.1 to 84.5%. The Langmuir model provided the best fit throughout the concentration range, and the maximum adsorption capacity (q_max) and Langmuir constant (b) were determined to be 135.14 mg/g and 0.026 l/mg, respectively. Furthermore, the biosorbent process of R. glutinis was found to follow pseudo-second-order kinetics and the calculated q_eq,cal value showed good agreement with the experimental q_eq value. Overall, the biosorption of MB by R. glutinis can be characterized as a monolayer, single site type phenomenon, and the rate-limiting step was determined to be the chemical reaction between the adsorbent and the adsorbate.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.3
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• pp.69-74
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• 2009

This paper summarizes the analysis of granite microfines from California for use in portland cement concrete. For reference, the granite microfines were compared to microfines used in previous International Center for Aggregates Research(ICAR) projects. The particle shape characteristics, based on the packing density results, were assessed and apparent clay content, based on the methylene blue value test, was evaluated. Also, the physical properties of the microfines were confirmed in self-consolidating mortar mixtures.

• Advances in nano research
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• v.12 no.4
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• pp.415-426
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• 2022

Nickel substituted cobalt-zinc ferrite nanoparticles with composition Co_0.5Zn_0.5Ni_xFe_2-xO₄ (x = 0.25, 0.5, 0.75, 1.0) were synthesized using a wet chemical method named citrate precursor method. Various characterizations of the prepared nanoferrites were done using X-ray powder diffractometry (XRD), Scanning electron microscopy (SEM), UV visible spectroscopy and Fourier transform spectroscopy technique (FT-IR). XRD confirmed the formation of cubic spinel structure of the samples with single phase having one characteristic peak at (311). The value of optical band gap (E_g) was found to decrease with Ni substitution and have values in the range 2.30eV to 1.69eV. A Fenton-type system was created by photocatalytic activity using source of visible light for removal of methylene blue dye. Observations revealed increase in the degradation of methylene blue dye with increasing nickel content in the samples. The degradation percentage was increased from 77.32% for x = 0.25 to 90.16% for x = 1.0 in one hour under the irradiation of visible light. Also, the degradation process was found to have pseudo first order kinetics model. Hence, it can be observed that synthesized nickel doped cobalt-zinc ferrites have good capability for water purification and its degradation efficiency enhanced with increase in nickel concentration.

• Journal of the Korean Chemical Society
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• v.31 no.4
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• pp.295-300
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• 1987

Spectroscopic studies have been carried out on the metachromatic behavior of methylene blue(MB) and acridine orange(AO) in the presence of chondroitin sulfate A(CSA) and chondroitin sulfate C(CSC). The characteristic changes of the meta-band with the changes of P/D value are discussed in terms of the stacking theory. Quantitative studies on the stacking effect are made to calculate the number of bound molecules of dye per unit molecule of the polyanion. The result shows that MB has stronger stacking effect than AO. A stacking model and the dimension of the bound dyes on the surface of the polyanion are proposed, on the basis of the dimer model of planar aromatic dyes and the most stable conformation of the CSA chain. The model is found to be reasonable in accordance with the experimental results.

• Journal of the Korean Chemical Society
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• v.30 no.3
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• pp.289-295
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• 1986

Spectroscopic studies have been carried out on the metachromatic behavior of methylene blue(MB) and acridine orange(AO) in the presence of polyvinylsulfate(PVS) and polystyrenesulfonate(PSS) The characteristic changes of meta-band with the change of P/D value are discussed in terms of stacking theory. It has been found that the stacking effect in the PVS-dye system is stronger than that in the PSS-dye system and that MB shows stronger stacking effect than AO. A stacking model and dimension of bound dyes on the surface of polymer chain is proposed on the basis of the previously suggested model of dimer found in the aqueous solution of planar aromatic dyes. The proposed model is found to be reasonable in accordance with the experimental results obtained by various workers.

• Journal of the Korean Chemical Society
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• v.26 no.5
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• pp.326-332
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• 1982

The structure of the complex extracted from an aqueous solution containing methylene blue and tetrafluoroborate with 1,2-dichloroethane has been investigated by comparing IR spectrum of the extract with those of pure components and appeared to be an 1 : 1 contact ion-pair between monovalent ions of opposite charge. The extraction constant obtained from the absorbance data measured at 658nm in 1,2-dichlorethane has a value of 1.1${\times}$at$10^4M{-1}$ 25$^{\circ}$C in the range from 1.43${\times}10^{-2}$ to 2.86${\times}10^{-1}$M HF. In the solvent extraction with nitrobenzene, the identical experiments show that extraction constants are increased with HF concentration possibly due to dissociation of the ion-pair in nitrobenzene.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.4
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• pp.416-424
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• 1999

Simulation of naturally appearing enamel in fixed prosthodontics could be achieved with all ceramics. The purpose of this study was to investigate the stain resistance of 4 different all ceramics materials (In-ceram, IPS Empress, Celay, Vintage). Forty specimens were prepared using manifacture's instruction and the samples were divided into two groups. The specimens for one group were glazing and those for other group were ground to remove the glazing layer. All specimens were immersed in methylene-blue for 24hours. The color values for each specimen was measured with colorimeter (Mode Tc-6Fx, Tokyo Denshoku Co.) prior to and after immersion in methylene-blue. The following conclusions were drawn from this study. 1 The stain resistance of glazing ceramics was higher than that of unglazing ceramics. 2. The changes of ${\Delta}E^*$\;and\;L^*$ values were revealed in Vintage and unglazing Celay. 3. The changes of $a^*$ values were revealed in unglazing vintage, Celay, In-ceram. 4. The changes of $b^*$ value were revealed in Vintage, IPS Empress and unglazing Celay.