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Showing 1 to 20 of 29 for “"Freundlich isotherm"”.
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The adsorption of vinyl chloride and vinylidene chloride monomers on their polymers
… was very slow and as a result only approximate isotherms could be obtained. These isotherms were shown to exhibit hysteresis. Comparison of the amount of monomer adsorbed at the higher pressures within the above limits, with the amount of krypton required to cover the surface with a monolayer, …
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Characterization and modeling of soluble manganese removal from drinking water by oxide-coated filter media
… the surface species found by XPS analysis. The Freundlich isotherm described Mn²⁺ sorption on this and the naturally coated media; sorption capacity increased between pH 6.0 and 7.5, and was reduced by [Ca²⁺] = 60 mg L⁻¹. The global Mn²⁺ oxidation rates for all coated media at pH 7.5 were 0.008 …
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Land Use Impacts of Plastic Mulch Tomato Production and Evaluation of Sorbent Control on Shellfish Hatchery Operations
… an ion exchange resin, Amberlite IRC-718. These isotherm studies showed that all sorbents removed soluble copper, and that increased salinity and a greater contact time were shown to increase sorption. Utilizing the Freundlich isotherm, the capacity of the eight sorbents studies ranged from 25 to …
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Kinetics, mass transfer, and mass re-equilibrium for arsenate adsorption on iron oxide-based carbons
… time in small water treatment systems. … The Freundlich isotherm can fit experimental data well: a crossover point for the two fitted Freundlich isotherms was observed and nano-FeAC had higher adsorption plateau. Furthermore, we demonstrated that due to the MRE process, a pseudo-equilibrium of …
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ADSORPTION OF ANTIBIOTICS BY VERMICULITE
… adsorption techniques. The Langmuir and Freundlich isotherm models were initially used to explain the adsorption processes. The separation factor (RL) values derived from the Langmuir model and the 1/n values derived from Freundlich model in the present investigation were less than one, …
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The purification of industrial wastewater to remove heavy metals and investigation into the use of zeolite as a remediation tool
… and lead respectively. Both the Langmuir and Freundlich isotherm models were used to characterize the experimental data and to assess the adsorption behaviour of natural zeolite for copper, iron, lead and zinc. The experimental data were slightly better suited to the Langmuir isotherm than the …
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Adsorption of Single and Multi-Component Per-and Polyfluoroalkyl Substances (PFAS) at Air-Water Interfaces
… (PFOS) adsorption was better predicted by the Freundlich isotherm than the Langmuir isotherm. Varying pore-water velocity revealed that lower velocities increased retardation at lower PFOS concentrations due to the presence of diffusion-limited domains in quasi-saturated conditions. …
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Evaluation of economical sorbents for the removal of metolachlor from contaminated wastewater
… metolachlor were best described by the Freundlich isotherm model. Metolachlor was preferentially sorbed in the following order: rubber > peat > wood fibers, with removal efficiencies of 80-85%, 70-80% and 50-65%, respectively. Differences in slopes of the isotherm lines and K values were …
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Color Removal From Pulp Mill Effluent Using Coal Ash Produced From Georgia Power Coal Combustion Plants
… determine their effect on removal. Kinetic and isotherm studies were also conducted using the optimal conditions, and the data was fitted to existing adsorption models. In addition, a column study was completed to observe CFA in a continuous flow setting. The research produced a cost-effective …
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Defluoridation of Water Using Silica Based Aluminum Coated Adsorbents
… kinetics and fit Langmuir and Freundlich isotherm models, indicating favorable adsorption. Sorbent regeneration and reuse were investigated through re-coating techniques using the original coating solutions. The re-coated AMCCS and CMCS sorbents maintained high removal …
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The Removal of Trace Organic Impurities from Water using Activated Charcol Cloth
… capacity of the cloth was found, using the Freundlich isotherm, to be between three and four times greater than for granular charcoal, under normal conditions. In order effectively to model a system using charcoal cloth, it was necessary to establish the kinetics of adsorption on the cloth. …
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Development and Comparison of 17beta-Estradiol Sorption Isotherms for Three Agriculturally Productive Soils From Different Physiographic Regions in Virginia
… to reach equilibrium and to develop sorption isotherms for each soil. The time required to reach equilibrium for all soils was less than 24 hours. A linear isotherm provided the best fit to model the sorption of E2 to Cecil and Myatt soils (R2 = 0.94 and 0.96, respectively). For Groseclose …
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The use of a calibrated three phase (solid-aqueous-gas) plant-wide wastewater treatment model to simulate data on mineral precipitation
… could be described using the Langmuir and Freundlich isotherm model. Regardless of the adsorbent studied, Langmuir isotherm model fitted well with the adsorption data. The maximum adsorption capacity was found to be 66 mg/g for HC-PS-WAS and 60 mg/g for GAC. The adsorption kinetics could …
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Effects of copper on nitrification and denitrification of leachate from an abandoned landfill
… liquor, could be generally described by the Freundlich Isotherm. Intermittent inhibition of nitrification unrelated to copper addition also occurred during treatment of the landfill leachate which was obtained from the abandoned Dixie Caverns Landfill near Roanoke, Virginia. The inhibiting …
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Quantification of Parameters in Models for Contaminant Dissolution and Desorption in Groundwater
… which represented sorption/desorption using a Freundlich isotherm. The results suggest that first-order/Freundlich models can reproduce dynamic desorption attributed to high-and-low relative energy sorption sites. However, additional experimentation with the inversion method suggests that mass …
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Cellulose-metal organic framework nanocomposite adsorbent films for water remediation
… % removals between 77 - 85 %. The adsorption isotherms and kinetic models revealed multilayer chemical adsorption on the surface of film 1 as indicated by the experimental results which were best described by the Freundlich isotherm and pseudo-second-order kinetic models. On the surfaces of …
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The Development of Sustainable Hydrometallurgical Processes for the Recovery of Precious Metal
… with a value of 59.86 kJ/mol. The adsorption isotherm is found to follow Freundlich isotherm model, which might have favored the formation of gold flakes on the adsorbent. The CV experiment shows the disappearance of anodic peaks as the adsorption of gold progresses, which is an indication of …
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Functional Characterization of Green Sorption Media and Scaling of Pilot Studies for Copper Removal in Stormwater Runoff
… individual media components including studies of isotherm, reaction kinetics, column adsorption and reaction kinetics. Batch adsorption tests revealed that the media and media mixture follow both the Freundlich and Langmuir isotherm models and that the coconut coir had the highest affinity for …
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Development of teawaste based bio-sorbent materials for removal of Cr(VI) from wastewater
… were investigated, and the adsorption kinetic, isotherm and thermodynamic parameter of hexavalent chromium by MBTW was analyzed. The results showed that, magnetic bleached teawaste biosorbent (MBTW) the maximum adsorption capacity Qmax was 124 mg/g. At 2.5 g/L, pH=2 and 100 ppm, MBTW equilibrium …
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Climate Change and Dissolved Organic Matter in Subarctic Lakes: Relevance to Methylmercury Bioavailability
One of the first steps of methylmercury (MeHg) bioaccumulation, uptake by phytoplankton, is regulated by dissolved organic matter (DOM). Methylmercury binds strongly with DOM, especially high-molecular weight (HMW) compounds containing reduced sulphur; this binding decreases MeHg bioavailability. …
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