• Title/Summary/Keyword: Freundlich Isotherm

Search Result 420, Processing Time 0.027 seconds

Dyeing Properties and Antimicrobial Activity of Soybean Fiber with Gromwell Colorants (대두섬유에 대한 자초색소의 염색성 및 항균성)

  • Choi, Hee;Shin, Youn-Sook;Choi, Chang-Nam;Kim, Sang-Yool;Chung, Yong-Sik
    • Fashion & Textile Research Journal
    • /
    • v.9 no.1
    • /
    • pp.119-123
    • /
    • 2007
  • Dyeing properties of soybean fabrics on gromwell colorants were studied for the effect of dyeing conditions, such as colorants concentration, temperature, time and pH on the dye uptake and effect of mordants on color change, dye uptake and various colorfastness. Antimicrobial activity of soybean fabrics dyed and sim-mordanted with gromwell colorants was examined by shake flask method. Gromwell colorants showed considerably affinity to soybean fabric and its isotherm adsorption curve was Freundlich type. Therefore, it is considered that hydrogen bonding and Van der Waals force were involved in the adsorption of gromwell colorants to soybean fabric. Soybean fabrics showed R color on Al, Cu and Sn mordant, RP color on Cr and Fe mordant, but soybean fabrics showed low dye uptake depending on mordanting treatment. Light colorfastness was increased for Cr and Fe mordants. Staphylococcus aureus reduction rates were above 90% for Cr and Cu mordanted soybean fabrics, and the others were poor. Klebsiella pneumoniae reduction rates soybean fabrics did not show reduction rate hardly.

Development of Loess Composite for the Control of Phosphorus Release from Lake Sediments (호소 퇴적층으로부터 용출되는 인 제거를 위한 황토 복합체 개발)

  • Shin, Gwan-Woo;Kim, Keum-Yong;Lee, Sang-Ill
    • Journal of Korean Society on Water Environment
    • /
    • v.28 no.1
    • /
    • pp.50-56
    • /
    • 2012
  • In this study, loess composites, loess with lanthanum and with aluminum, were made and evaluated for treatment of phosphorus removal in natural water system. Desiccation method for production of loess composite was superior to centrifugation method in obtaining high concentrated composites of lanthanum and aluminum. Washing of loess lanthanum composite by water did not deteriorat the lanthanum concentration in the composite, but this lowered the aluminum concentration of loess aluminum composite. Total of 15 and 37.5% of aluminum contents were removed after first washing treatment in aluminum loess of 0.05% and 0.1% respectively. However, no more aluminum loss was monitored with increase of washing times. Phosphorus removal efficiencies were not decreased with washed loess aluminum composite. Phosphorus removal was successfully achieved by adsorption of phosphate to loess composite at pH range of 5.0 ~ 8.0. Freundlich and Langmuir adsorption isotherm was observed in the adsorption of phosphate for loess composite. Dosages of 0.05% and 0.1% lanthanum composite for 95% of phosphorus removal could reduce its usage amount to 25% and 50%, respectively, comparing with dosage of loess alone. Dosages of 0.05% and 0.1% aluminum composite could reduce its usage amount to 48% and 63%, respectively.

Phosphate removal efficiency and the removal rate constant by particle sizes of converter slag and conditions of the wastewater (전로슬래그의 입도 크기 및 폐수의 조건 변화에 따른 인산염 제거효율과 제거 속도상수에 관한 연구)

  • Lee, Sang Ho;Hwang, Jeong Jae
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.26 no.6
    • /
    • pp.841-849
    • /
    • 2012
  • The effluent quality of phosphorus is strengthened by the national standard to conserve water resources to lessen the eutrophication threat. The soluble phosphate in the wastewater effluent can be removed using the converter slag as solid waste produced through the steel making process. The experiments for removal efficiencies and removal constants were performed for this research with the artificial wastewater following several different conditions, particle size, phosphate concentration and initial pH. The correlation coefficients of Freundlich adsorption isothem were 0.9505 for $PS_A$, 0.9183 for $PS_B$, respectively. The removal efficiency was 87-94 % for $PS_A$ and 90-96 % for $PS_B$ respectively. The pH of the wastewater was elevated to pH 11.8 for the initial pH 8.5, phosphate removal efficiency was the highest as 84 % ~ 98 %. In case of 10 mg/L of the intial phosphate, the removal efficiency was 96 ~ 98 %. The more initial pH increases, the higher the reaction rate constant is.

Adsorption Characteristics of Lithium Ion by Zeolite Modified in K+, Na+, Mg2+, Ca2+, and Al3+ Forms (양이온 K+, Na+, Mg2+, Ca2+, Al3+ 형태로 개질한 제올라이트에 의한 리튬 이온의 흡착 특성)

  • Park, Jeong-Min;Kam, Sang-Kyu;Lee, Min-Gyu
    • Journal of Environmental Science International
    • /
    • v.22 no.12
    • /
    • pp.1651-1660
    • /
    • 2013
  • The adsorption of lithium ion onto zeolite was investigated depending on contact time, initial concentration, cation forms, pH, and adsorption isotherms by employing batch adsorption experiment. The zeolite was converted into different forms such $K^+$, $Na^+$, $Mg^{2+}$, $Ca^{2+}$, and $Al^{3+}$. The zeolite had the higher adsorption capacity of lithium ion in $K^+$ form followed by $Na^+$, $Ca^{2+}$, $Mg^{2+}$, and $Al^{3+}$ forms, which was in accordance with their elctronegativities. The lithium ion adsorption was explained using the Langmuir, Freundlich, and Dubinin-Radushkevich adsorption isotherms and kinetic models. Adsorption rate of lithium ion by zeolite modified in $K^+$ form was controlled by pseudo-second-order and particle diffusion kinetic models. The maximum adsorption capacity obtained from Langmuir isotherm was 17.0 mg/g for zeolite modified in $K^+$ form. The solution pH influenced significantly the lithium ions adsorption capacity and best results were obtained at pH 5-10.

Phosphate Removal of Aqueous Solutions using Industrial Wastes (산업폐기물을 이용한 수용액 중 인산염의 흡착 제거)

  • Kang, Ku;Kim, Young-Kee;Park, Seong-Jik
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.55 no.1
    • /
    • pp.49-57
    • /
    • 2013
  • The present study was conducted to investigate phosphate removal from aqueous solution using industrial wastes, red mud (RM), acid treated red mud (ATRM) and converter furnace steel slag (CFSS). The chemical composition of adsorbents was analyzed using X-ray fluorescence (XRF). Batch experiments and elution experiments using water tank were performed to examine environmental factors that influences on phosphate removal. Kinetic sorption data of RM, ATRM, and CFSS were described well by the pseudo second-order kinetic sorption model, and equilibrium sorption data of all adsorbents obeyed Freundlich isotherm model. The adsorption capacities of adsorbents followed order: ATRM (7.06 mg/g)>RM (4.34 mg/g)>CFSS (1.88 mg/g). Increasing pH from 3 to 11, the amount of adsorbed phosphate on all RM, ATRM, and CFSS were decreased. The presence of sulfate and carbonate decreased the phosphate removal of RM and ATRM but did not influence on the performance of CFSS. The phosphate removal of RM, ATRM, and CFSS was greater in seawater than deionized water, resulting from the presence of cations in seawater. The water tank elution experiments showed that RM capping blocked the elution of phosphate effectively. It was concluded that the adsorbents can be successfully used for the removal of the phosphate from the aqueous solutions.

Cost-effective polyvinylchloride-based adsorbing membrane for cationic dye removal

  • Namvar-Mahboub, Mahdieh;Jafari, Zahra;Khojasteh, Yasaman
    • Membrane and Water Treatment
    • /
    • v.11 no.2
    • /
    • pp.131-139
    • /
    • 2020
  • The current study focused on the preparation of low-cost PVC-based adsorbing membrane. Metakaolin, as available adsorbent, was embedded into the PVC matrix via solution blending method. The as-prepared PVC/metakaolin mixed matrix membranes were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, atomic force microscopy (AFM), pure water permeability and contact angle measurements. The results confirmed the improvement of PWP and hydrophilicity due to the presence of metakaolin in the PVC matrix. Additionally the structure of PVC membrane was changed due to the incorporation of metakaolin in the polymer matrix. The static adsorption capacity of all samples was determined through dye removal. The effect of metakaolin dosage (0-7%) and pH (4, 8, 12) on dye adsorption capacity was investigated. The results depicted that the highest adsorption capacity was achieved at pH of 4 for all samples. Additionally, adsorption data were fitted on Langmuir, Freundlich, and Temkin models to determine the appropriate governing isotherm model. Finally, the dynamic adsorption capacity of the optimum PVC/metakaolin membrane was studied using dead-end filtration cell. The dye removal efficiency was determined for pure PVC and PVC/metakaolin membrane. The results demonstrated that PVC/metakaolin mixed matrix membrane had a high adsorption capacity for dye removal from aqueous solution.

Prediction of chloride ingress into saturated concrete on the basis of a multi-species model by numerical calculations

  • Nguyen, T.Q.;Baroghel-Bouny, V.;Dangla, P.
    • Computers and Concrete
    • /
    • v.3 no.6
    • /
    • pp.401-422
    • /
    • 2006
  • A multi-species model based on the Nernst-Planck equation has been developed by using a finite volume method. The model makes it possible to simulate transport due to an electrical field or by diffusion and to predict chloride penetration through water saturated concrete. The model is used in this paper to assess and analyse chloride diffusion coefficients and chloride binding isotherms. The experimental assessment of the effective chloride diffusion coefficient consists in measuring the chloride penetration depth by using a colorimetric method. The effective diffusion coefficient determined numerically allows to correctly reproduce the chloride penetration depth measured experimentally. Then, a new approach for the determination of chloride binding, based on non-steady state diffusion tests, is proposed. The binding isotherm is identified by a numerical inverse method from a single experimental total chloride concentration profile obtained at a given exposure time and from Freundlich's formula. In order to determine the initial pore solution composition (required as initial conditions for the model), the method of Taylor that describes the release of alkalis from cement and alkali sorption by the hydration products is used here. Finally, with these input data, prediction of total and water-soluble chloride concentration profiles has been performed. The method is validated by comparing the results of numerical simulations to experimental results obtained on various types of concretes and under different exposure conditions.

Functionalized magnetite / silica nanocomposite for oily wastewater treatment

  • Hakimabadi, Seyfollah Gilak;Ahmadpour, Ali;Mosavian, Mohammad T. Hamed;Bastami, Tahereh Rohani
    • Advances in environmental research
    • /
    • v.4 no.2
    • /
    • pp.69-81
    • /
    • 2015
  • A new magnetite-silica core/shell nanocomposite ($Fe_3O4@nSiO_2@mSiO_2$) was synthesized and functionalized with trimethylchlorosilane (TMCS). The prepared nanocomposite was used for the removal of diesel oil from aqueous media. The characterization of magnetite-silica nanocomposite was studied by X-ray diffraction (XRD), Fourier transform infrared (FTIR), transmission electron microscopy (TEM), surface area measurement, and vibrating sample magnetization (VSM). Results have shown that the desired structure was obtained and surface modification was successfully carried out. FTIR analysis has confirmed the presence of TMCS on the surface of magnetite silica nanocomposites. The low- angle XRD pattern of nanocomposites indicated the mesoscopic structure of silica shell. Furthermore, TEM results have shown the core/shell structure with porous silica shell. Adsorption kinetic studies indicated that the nanocomposite was able to remove 80% of the oil contaminant during 2 h and fit well with the pseudo-second order model. Equilibrium studies at room temperature showed that the experimental data fitted well with Freundlich isotherm. The magnetic property of nanocomposite facilitated the separation of solid phase from aqueous solution.

Sorption of chlorophenols on geotextile of the geosynthetic clay liners

  • Ahari, M'hamed;Touze-Foltz, Nathalie;Mazeas, Laurent
    • Environmental Engineering Research
    • /
    • v.25 no.2
    • /
    • pp.163-170
    • /
    • 2020
  • Knowledge of organic micropollutant transfers in barrier seal materials from waste storage facilities is limited to volatile organic compounds and phenolic compounds at ambient temperature. This study focused on the sorption of chlorophenols (CPs) from various geotextiles from clay geosynthetics under the influence of temperature. Also to study the impact of the polarity or the amount of CPs adsorbed on geotextiles with the partition coefficient. The effect of various parameters such as contact time, effect of temperature, initial CPs concentration and adsorbent dosage has been carried out in this study. The result obtained is non-linear and the data was calculated for affinity with Freundlich isotherm model. An important observation is that the amount of CPs sorbed on geotextiles increases with a growing number of chlorine atoms, ie increases with the partition coefficient (log Kow). During this study, a decrease in adsorbent properties was observed with the rise in temperature from 23℃ to 55℃. The partitioning coefficients for CPs examined range are from 2.4 (R2 = 0.86) to 8.4 mL/g (R2 = 0.90). Among the CPs studied, the highest adsorbed quantity was observed for pentachlorophenol with 0.052 g/g at 23℃, this quantity will decrease with the increase in temperature.

Removal Characteristics of Sr Ion by Na-A Zeolite Synthesized using Coal Fly Ash Generated from a Thermal Power Plant (화력발전소에서 발생하는 석탄비산재로부터 합성한 Na-A 제올라이트의 Sr 이온 제거 특성)

  • Lee, Chang-Han;Kam, Sang-Kyu;Lee, Min-Gyu
    • Journal of Environmental Science International
    • /
    • v.26 no.3
    • /
    • pp.363-371
    • /
    • 2017
  • This study evaluates the adsorption properties of Sr ions in an aqueous solution of the synthetic zeolite (Z-Y1) prepared using coal fly ash generated from a thermal power plant. In order to investigate the adsorption characteristics, the effects of various parameters such as the initial concentrations of Sr ion, contact time, and solution pH were investigated in a batch mode. The Langmuir and Redlich-Peterson model fitted the adsorption isotherm data better than the Freundlich model. The maximum adsorption capacity of Sr ions, as determined the Langmuir model, was 181.68 mg/g. It was found that by varying the Sr ion concentration, pH, and temperature, the pseudo-second-order kinetic model describes the adsorption kinetics of the Sr ion better than the pseudo-first-order kinetic model. The calculated thermodynamic parameters of ${\Delta}H^0$ and ${\Delta}G^0$ showed that the adsorption of Sr ions on Z-Y1 was occurred through a spontaneous and an endothermic reaction. We found that the adsorption of Sr ions by Z-Y1 was more affected by pH than by temperature and Sr ion concentration.