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C Namasivayam - One of the best experts on this subject based on the ideXlab platform.

  • experimental and kinetic studies on methylene blue Adsorption by coir pith carbon
    Bioresource Technology, 2007
    Co-Authors: D Kavitha, C Namasivayam
    Abstract:

    Varying the parameters such as agitation time, Dye concentration, adsorbent dose, pH and temperature carried out the potential feasibility of thermally activated coir pith carbon prepared from coconut husk for removal of methylene blue. Greater percentage of Dye was removed with decrease in the initial concentration of Dye and increase in amount of adsorbent used. Kinetic study showed that the Adsorption of Dye on coir pith carbon was a gradual process. Lagergren first-order, second-order, intra particle diffusion model and Bangham were used to fit the experimental data. Equilibrium isotherms were analysed by Langmuir, Freundlich, Dubnin-Radushkevich, and Tempkin isotherm. The Adsorption capacity was found to be 5.87 mg/g by Langmuir isotherm for the particle size 250-500 microm. The equilibrium time was found to be 30 and 60 min for 10 and 20 mg/L and 100 min for 30, 40 mg/L Dye concentrations, respectively. A maximum removal of 97% was obtained at natural pH 6.9 for an adsorbent dose of 100 mg/50 mL and 100% removal was obtained for an adsorbent dose of 600 mg/50 mL of 10 mg/L Dye concentration. The pH effect and desorption studies suggest that chemisorption might be the major mode of the Adsorption process. The change in entropy (DeltaS0) and heat of Adsorption (DeltaH0) of coir pith carbon was estimated as 117.20 J/mol/K and 30.88 kJ/mol, respectively. The high negative value of change in Gibbs free energy indicates the feasible and spontaneous Adsorption of methylene blue on coir pith carbon.

  • experimental and kinetic studies on methylene blue Adsorption by coir pith carbon
    Bioresource Technology, 2007
    Co-Authors: D Kavitha, C Namasivayam
    Abstract:

    Abstract Varying the parameters such as agitation time, Dye concentration, adsorbent dose, pH and temperature carried out the potential feasibility of thermally activated coir pith carbon prepared from coconut husk for removal of methylene blue. Greater percentage of Dye was removed with decrease in the initial concentration of Dye and increase in amount of adsorbent used. Kinetic study showed that the Adsorption of Dye on coir pith carbon was a gradual process. Lagergren first-order, second-order, intra particle diffusion model and Bangham were used to fit the experimental data. Equilibrium isotherms were analysed by Langmuir, Freundlich, Dubnin–Radushkevich, and Tempkin isotherm. The Adsorption capacity was found to be 5.87 mg/g by Langmuir isotherm for the particle size 250–500 μm. The equilibrium time was found to be 30 and 60 min for 10 and 20 mg/L and 100 min for 30, 40 mg/L Dye concentrations, respectively. A maximum removal of 97% was obtained at natural pH 6.9 for an adsorbent dose of 100 mg/50 mL and 100% removal was obtained for an adsorbent dose of 600 mg/50 mL of 10 mg/L Dye concentration. The pH effect and desorption studies suggest that chemisorption might be the major mode of the Adsorption process. The change in entropy (Δ S 0 ) and heat of Adsorption (Δ H 0 ) of coir pith carbon was estimated as 117.20 J/mol/K and 30.88 kJ/mol, respectively. The high negative value of change in Gibbs free energy indicates the feasible and spontaneous Adsorption of methylene blue on coir pith carbon.

  • recycling coir pith an agricultural solid waste for the removal of procion orange from wastewater
    Dyes and Pigments, 2007
    Co-Authors: D Kavitha, C Namasivayam
    Abstract:

    Abstract Batch Adsorption experiments were carried out for the removal of procion orange from its aqueous solution using coir pith carbon. This study examines Adsorption kinetic parameters on coir pith carbon. The effect of process parameters like contact time, concentration of Dye, temperature and pH on the extent of procion orange Adsorption from solution has been investigated. In order to develop an effective and accurate design model for removal of Dye, Adsorption kinetics and equilibrium data are essential basic requirements. Kinetic study showed that the Adsorption of Dye on coir pith carbon was a gradual process. Lagergren first-order, second-order, Bangham's and intra-particle diffusion model were used to fit the experimental data. Results of the kinetic studies show that the Adsorption reaction is second-order kinetic model with respect to Dye solution concentration. Equilibrium isotherms were analyzed by Langmuir, Freundlich, Dubnin–Radushkevich, and Tempkin isotherms. The Adsorption equilibrium data obeyed Langmuir, Dubnin–Radushkevich, and Tempkin isotherms. The Adsorption capacity was found to be 2.6 mg/g of carbon. Increase of temperature increased Adsorption. Acidic pH was favorable for the Adsorption of Dye. Studies on pH effect and desorption show that chemisorption seems to play a major role in the Adsorption process.

  • removal of direct red and acid brilliant blue by Adsorption on to banana pith
    Bioresource Technology, 1998
    Co-Authors: C Namasivayam, D Prabha, M Kumutha
    Abstract:

    Abstract The Adsorption of direct red and acid brilliant blue by waste banana pith was investigated by varying the agitation time, Dye concentration, adsorbent dose and pH. The Adsorption followed both Langmuir and Freundlich isotherms. The Adsorption capacity was 5·92 and 4·42 mg Dye per gram of the adsorbent for direct red and acid brilliant blue, respectively. Adsorption of Dye followed first-order kinetics. An acidic pH was favourable for the Adsorption of both Dyes. An alkaline pH was favourable for desorption of the Dyes.

  • Adsorption of direct red 12 b by biogas residual slurry equilibrium and rate processes
    Environmental Pollution, 1995
    Co-Authors: C Namasivayam, R T Yamuna
    Abstract:

    Abstract The rate of Adsorption of Direct red 12 B, a direct Dye, on biogas residual slurry (BRS) has been studied. The parameters studied include Dye concentration, particle size, temperature and pH. The rate controlling step is mainly intraparticle diffusion, although a small boundary layer resistance is expressed. Almost total removal of Dye occurred at pH 2·3. Adsorption of Dye conforms with the Freundlich isotherm.

D Kavitha - One of the best experts on this subject based on the ideXlab platform.

  • experimental and kinetic studies on methylene blue Adsorption by coir pith carbon
    Bioresource Technology, 2007
    Co-Authors: D Kavitha, C Namasivayam
    Abstract:

    Varying the parameters such as agitation time, Dye concentration, adsorbent dose, pH and temperature carried out the potential feasibility of thermally activated coir pith carbon prepared from coconut husk for removal of methylene blue. Greater percentage of Dye was removed with decrease in the initial concentration of Dye and increase in amount of adsorbent used. Kinetic study showed that the Adsorption of Dye on coir pith carbon was a gradual process. Lagergren first-order, second-order, intra particle diffusion model and Bangham were used to fit the experimental data. Equilibrium isotherms were analysed by Langmuir, Freundlich, Dubnin-Radushkevich, and Tempkin isotherm. The Adsorption capacity was found to be 5.87 mg/g by Langmuir isotherm for the particle size 250-500 microm. The equilibrium time was found to be 30 and 60 min for 10 and 20 mg/L and 100 min for 30, 40 mg/L Dye concentrations, respectively. A maximum removal of 97% was obtained at natural pH 6.9 for an adsorbent dose of 100 mg/50 mL and 100% removal was obtained for an adsorbent dose of 600 mg/50 mL of 10 mg/L Dye concentration. The pH effect and desorption studies suggest that chemisorption might be the major mode of the Adsorption process. The change in entropy (DeltaS0) and heat of Adsorption (DeltaH0) of coir pith carbon was estimated as 117.20 J/mol/K and 30.88 kJ/mol, respectively. The high negative value of change in Gibbs free energy indicates the feasible and spontaneous Adsorption of methylene blue on coir pith carbon.

  • experimental and kinetic studies on methylene blue Adsorption by coir pith carbon
    Bioresource Technology, 2007
    Co-Authors: D Kavitha, C Namasivayam
    Abstract:

    Abstract Varying the parameters such as agitation time, Dye concentration, adsorbent dose, pH and temperature carried out the potential feasibility of thermally activated coir pith carbon prepared from coconut husk for removal of methylene blue. Greater percentage of Dye was removed with decrease in the initial concentration of Dye and increase in amount of adsorbent used. Kinetic study showed that the Adsorption of Dye on coir pith carbon was a gradual process. Lagergren first-order, second-order, intra particle diffusion model and Bangham were used to fit the experimental data. Equilibrium isotherms were analysed by Langmuir, Freundlich, Dubnin–Radushkevich, and Tempkin isotherm. The Adsorption capacity was found to be 5.87 mg/g by Langmuir isotherm for the particle size 250–500 μm. The equilibrium time was found to be 30 and 60 min for 10 and 20 mg/L and 100 min for 30, 40 mg/L Dye concentrations, respectively. A maximum removal of 97% was obtained at natural pH 6.9 for an adsorbent dose of 100 mg/50 mL and 100% removal was obtained for an adsorbent dose of 600 mg/50 mL of 10 mg/L Dye concentration. The pH effect and desorption studies suggest that chemisorption might be the major mode of the Adsorption process. The change in entropy (Δ S 0 ) and heat of Adsorption (Δ H 0 ) of coir pith carbon was estimated as 117.20 J/mol/K and 30.88 kJ/mol, respectively. The high negative value of change in Gibbs free energy indicates the feasible and spontaneous Adsorption of methylene blue on coir pith carbon.

  • recycling coir pith an agricultural solid waste for the removal of procion orange from wastewater
    Dyes and Pigments, 2007
    Co-Authors: D Kavitha, C Namasivayam
    Abstract:

    Abstract Batch Adsorption experiments were carried out for the removal of procion orange from its aqueous solution using coir pith carbon. This study examines Adsorption kinetic parameters on coir pith carbon. The effect of process parameters like contact time, concentration of Dye, temperature and pH on the extent of procion orange Adsorption from solution has been investigated. In order to develop an effective and accurate design model for removal of Dye, Adsorption kinetics and equilibrium data are essential basic requirements. Kinetic study showed that the Adsorption of Dye on coir pith carbon was a gradual process. Lagergren first-order, second-order, Bangham's and intra-particle diffusion model were used to fit the experimental data. Results of the kinetic studies show that the Adsorption reaction is second-order kinetic model with respect to Dye solution concentration. Equilibrium isotherms were analyzed by Langmuir, Freundlich, Dubnin–Radushkevich, and Tempkin isotherms. The Adsorption equilibrium data obeyed Langmuir, Dubnin–Radushkevich, and Tempkin isotherms. The Adsorption capacity was found to be 2.6 mg/g of carbon. Increase of temperature increased Adsorption. Acidic pH was favorable for the Adsorption of Dye. Studies on pH effect and desorption show that chemisorption seems to play a major role in the Adsorption process.

Vinod Kumar Gupta - One of the best experts on this subject based on the ideXlab platform.

  • synthesis and Adsorption properties of mesoporous material for the removal of Dye safranin kinetics equilibrium and thermodynamics
    Journal of Industrial and Engineering Chemistry, 2015
    Co-Authors: Sumanjit Kaur, Seema Rani, Rakesh Kumar Mahajan, Mohammad Asif, Vinod Kumar Gupta
    Abstract:

    Abstract A highly ordered large pore mesoporous adsorbent MCM-41 is synthesized and characterized by XRD, BET, FTIR and SEM. Effect of contact time, initial Dye concentration, adsorbent dose, pH and temperature were studied for Adsorption of Dye safranin on MCM-41. Experimental data were investigated for various thermodynamic models and kinetic models and corroborated that Adsorption followed second order kinetic model. Langmuir model evidenced the maximum Adsorption capacity as 68.8 mg g −1 at 303 K. Thermodynamic parameters surmised that Adsorption of safranin on MCM-41 is spontaneous, exothermic and feasible.

  • Adsorption process of methyl orange Dye onto mesoporous carbon material kinetic and thermodynamic studies
    Journal of Colloid and Interface Science, 2011
    Co-Authors: Nourali Mohammadi, Ehsanollah Amereh, Hadi Khani, Vinod Kumar Gupta, Shilpi Agarwal
    Abstract:

    Abstract The mesoporous carbon CMK-3 adsorbent was prepared, characterized, and used for the removal of anionic methyl orange Dye from aqueous solution. Adsorption experiments were carried out as batch studies at different contact time, pH, initial Dye concentration, and salt concentration. The Dye Adsorption equilibrium was rapidly attained after 60 min of contact time. Removal of Dye in acidic solutions was better than in basic solutions. The Adsorption of Dye increased with increasing initial Dye concentration and salt concentration. The equilibrium data were analyzed by the Langmuir and Freundlich models, which revealed that Langmuir model was more suitable to describe the methyl orange Adsorption than Freundlich model. Experimental data were analyzed using pseudo-first-order and pseudo-second-order kinetic models. It was found that kinetics followed a pseudo-second-order equation. Thermodynamic study showed that the Adsorption was a spontaneous and exothermic process.

Mingshen Chiou - One of the best experts on this subject based on the ideXlab platform.

  • competitive Adsorption of Dye metanil yellow and rb15 in acid solutions on chemically cross linked chitosan beads
    Chemosphere, 2006
    Co-Authors: Mingshen Chiou, Guosyong Chuang
    Abstract:

    One kind of adsorbent with a high Adsorption capacity for anionic Dyes was prepared using ionically and chemically cross-linked chitosan beads. A batch system was applied to study the Adsorption behavior of one acid Dye (MY, metanil yellow) and one reactive Dye (RB15, reactive blue 15) in aqueous solutions by the cross-linked chitosan beads. The Adsorption capacities was 3.56 mmol g(-1) (1334 mg g(-1)) for Dye MY and 0.56 mmol g(-1) (722 mg g(-1)) for Dye RB15 at pH4, 30 degrees C. The Langmuir model agreed very well with the experimental data (R(2)>0.996). The kinetics of Adsorption for a single Dye and the kinetics of removal of ADMI color value in mixture solutions at different initial Dye concentrations were evaluated by the nonlinear first-order and second-order models. The first-order kinetic model fits well with the dynamical Adsorption behavior of a single Dye for lower initial Dye concentrations, while the second-order kinetic model fits well for higher initial Dye concentrations. The competitive Adsorption favored the Dye RB15 in the mixture solution (initial conc. (mM): MY=1.34; RB15=1.36); while it favored the Dye MY in the mixture solution (initial conc. (mM): MY=3.00; RB15=1.34) and the Adsorption kinetics for Dye RB15 has the tendency to shift to a slower first order model.

  • removal of reactive Dye from wastewater by Adsorption using ech cross linked chitosan beads as medium
    Journal of Environmental Science and Health Part A-toxic\ hazardous Substances & Environmental Engineering, 2003
    Co-Authors: Mingshen Chiou, Hsingya Li
    Abstract:

    Abstract The feasibility of the removal of reactive Dye from wastewater using a novel adsorbent, ECH cross-linked chitosan beads, as medium was examined. The effect of the pH and the initial concentration of the Dye (RR222) solution on the Adsorption capacity of the ECH cross-linked chitosan beads were also investigated. It was found that the initial Dye concentration and the pH of the solution significantly affected the Adsorption capacity. An increase in initial Dye concentration results in the increase of Adsorption capacity while an acidic pH was found to be favorable for the Adsorption of Dye. It was also found that the equilibrium Adsorption of RR222 could be adequately described by using the Langmuir model (r 2 ≥ 0.999). Moreover, results showed that the Adsorption rate of RR222 onto ECH cross-linked chitosan beads could be described by using the second-order kinetic model, suggesting that chemical sorption instead of mass transfer was the rate-limiting step for the Adsorption process. The maximum ...

Ragelienė Lina - One of the best experts on this subject based on the ideXlab platform.

  • Effect of the interaction between acid Dye and nonionic surfactants on the Adsorption of Dye in wool fibre
    2020
    Co-Authors: Musnickas Juozas, Skulkina Oksana, Treigienė Rasa, Ragelienė Lina
    Abstract:

    The binding behaviour of 1.4-diamine anthraquinone derivative disulphonic CI Acid Blue 80 Dye with nonionic surfactants based on ethoxylated alkylamines and fatty alcohols or alkylphenol (NPE) in aqueous solutions was investigated by means of conductivity measurements as well as by absorption spectroscopy. When the concentration of the surfactants was lower than the critical micellar concentration and the Dye/surfactant molar ratio was ca. 1:1, the interaction of the Dye with ethoxylated fatty alcohols or NPE was significantand dependent on temperature. It was established that the extent of interaction between the Dye and surfactant is in correlation with the results of Dye exhaustion from a Dyebath as well as the colour strength of Dyed wool fibreGamtos mokslų fakultetasKauno technologijos universitasVytauto Didžiojo universiteta

  • Vilnos pluošto apdoroto PAM tirpaluose dažymosi savybės
    2020
    Co-Authors: Musnickas Juozas, Treigienė Rasa, Ivanauskaitė A, Ragelienė Lina
    Abstract:

    The results of this study have showed that the pretreatment with different surfactants can be used as a way to improve the Dyeability of wool fibres. The colour strength (K/S) of the Dyeings as we] I as their wash fastness was determined. In particular, the uptake of CI Acid Blue 80 from Dye bath was the most-significantly enhanced when wool fabric was pretreated with the aqueuous solution of cationic Arquad HC. Colour strength (K/S) values of Dyeings prepared with application of zvitterionic cocamidopropylbetaine, nonionics alkoxyethoxylated alkohol C(12)-C(16), EO 7.5 or slightly cationic cocoalkylamine ethoxylate EO 15 were ca alike and generally the colour strength of Dyeings was improved up to 45% as compared with that for untreated fabric. It was noted the ability of surfactants; to improve the Adsorption of Dye onto the wool fiber as well as the washing fastness of Dyeings when all above mentioned surfactants used for the pretreatment of wool fibresBiochemijos katedraGamtos mokslų fakultetasKauno technologijos universitasKauno technologijos universitetasVytauto Didžiojo universiteta

  • Vilnos pluošto apdoroto PAM tirpaluose dažymosi savybės
    2020
    Co-Authors: Musnickas Juozas, Treigienė Rasa, Ivanauskaitė A, Ragelienė Lina
    Abstract:

    The results of this study have showed that the pretreatment with different surfactants can be used as a way to improve the Dyeability of wool fibres. The colour strength (K/S) of the Dyeings as we] I as their wash fastness was determined. In particular, the uptake of CI Acid Blue 80 from Dye bath was the most-significantly enhanced when wool fabric was pretreated with the aqueuous solution of cationic Arquad HC. Colour strength (K/S) values of Dyeings prepared with application of zvitterionic cocamidopropylbetaine, nonionics alkoxyethoxylated alkohol C(12)-C(16), EO 7.5 or slightly cationic cocoalkylamine ethoxylate EO 15 were ca alike and generally the colour strength of Dyeings was improved up to 45% as compared with that for untreated fabric. It was noted the ability of surfactants; to improve the Adsorption of Dye onto the wool fiber as well as the washing fastness of Dyeings when all above mentioned surfactants used for the pretreatment of wool fibresBiochemijos katedraKauno technologijos universitasKauno technologijos universitetasVytauto Didžiojo universiteta