An isothermal adsorption model for adsorption of substrates by anammox extracellular polymeric substance proteins: Establishment, verification, and determination of adsorption capacity

Pyridine is a toxic component in industrial wastewater, which is difficult to remove using conventional methods. In this study, the cost-effective coke powder was used to remove pyridine from a pyridine simulation wastewater. The removal efficiency and adsorption capacity of pyridine reached up to 67.32% and 0.4488 mg/g, respectively, at a coke powder concentration of 60 mg/L and an adsorption time of 30 min. The pyridine removal efficiency and adsorption capacity of coke powder reached saturation when the initial concentration was 40 mg/L. The pH of 2–12 in the solution was found to have little effect on the pyridine adsorption process of coke powder, while the coke powder with lower ash content was of better adsorbability for pyridine. The coke powder was regenerated by heat treatment, and reused for pyridine adsorption. It was found that the pyridine removal efficiency slightly decreased after nine times of reuse, in addition to a small cumulative weight loss rate of coke powder. Adsorption isotherm analysis showed that the adsorption of pyridine by coke powder could be well described by the Freundlich isothermal adsorption model, indicating multi-molecular layers mainly dominated the adsorption of pyridine on the surface of coke powder.

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Adsorption of Cu(II) on natural and treated clays

Water Quality Research Journal ◽

10.2166/wqrjc.2015.051 ◽

2015 ◽

Vol 51 (1) ◽

pp. 26-32 ◽

Cited By ~ 2

Author(s):

Mustapha Djebbar ◽

Fatiha Djafri

Keyword(s):

Adsorption Capacity ◽

Ph Value ◽

Copper Ions ◽

Low Cost ◽

Scale Up ◽

Adsorption Model ◽

X Ray Diffraction ◽

Monolayer Adsorption ◽

Equilibrium Data

We have studied the pH and the temperature effects on copper ions' adsorption on natural and treated clays from Algeria. The clay was also treated to improve the adsorption capacity. X-ray diffraction identified montmorillonite and kaolinite as major clay minerals. The Langmuir adsorption model was used for the mathematical description of the adsorption equilibrium and the equilibrium data adhered very well to this model. The treated and natural clay had a monolayer adsorption capacity equal to 15.40 and 12.22 mg/g, respectively, at pH value of 6.5 and temperature 20 °C, the adsorption isotherms could be fitted with Langmuir isotherms, and the coefficients indicated favorable adsorption of Cu(II) on the clays. Determination of the thermodynamic parameters, H, S, and G showed that the adsorption process was spontaneous and exothermic accompanied by a decrease in entropy and Gibbs energy. Results of this study will be useful for future scale-up for using this material as a low-cost adsorbent for the removal of Cu(II) from wastewater.

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Quantitative determination of organic adsorption capacity in the Palaeozoic shales from South China

Energy Exploration & Exploitation ◽

10.1177/0144598720983036 ◽

2021 ◽

pp. 014459872098303

Author(s):

Sibo Wang ◽

Zhiguang Song ◽

Jia Xia ◽

Yuan Gao ◽

YaoPing Wang ◽

...

Keyword(s):

Adsorption Capacity ◽

Clear Understanding ◽

Soluble Organic Matter ◽

Maximum Increase ◽

Immature Oil ◽

Methane Sorption ◽

Oil Shales ◽

The Impact ◽

Total Adsorption

In this study, the methane adsorption capacity of kerogen isolated from the Cambrian, Silurian, and Permian shales and the impact of soluble organic matter (SOM) on the adsorption capacity of these shales were investigated. The results reveal that 1) the adsorption capacity of kerogen varies in a broad range, from 14.48 to 23.22 cm3/g for the Cambrian kerogens, from 15.50 to 36.06 cm3/g for the Silurian kerogens, and from 10.71 to 11.15 cm3/g for the Permian kerogens; 2) the kerogen adsorption accounts for 33.67–70.23% of the total adsorption capacity of these Palaeozoic extracted shales, demonstrating that kerogen is the primary adsorbing substance in shales; 3) the adsorption isotherms of kerogen in highly mature Cambrian and Silurian shales are similar to those of Triassic coal, while the isotherms of kerogen in the relatively immature Permian shales are similar to those of the immature oil shales; and 4) the SOM demonstrates a significant impact on the adsorption capacity of shales as the removal of SOM can cause a maximum increase of 34.29% or a decrease of 23.36% in the total adsorption capacity of shales. However, there is no clear understanding of the impact of SOM on the methane sorption of shales.

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The extracellular polymeric substance of the green alga Penium margaritaceum and its role in biofilm formation

Biofilms ◽

10.1017/s147905050500181x ◽

2005 ◽

Vol 2 (2) ◽

pp. 129-144 ◽

Cited By ~ 43

Author(s):

D. S. Domozych ◽

S. Kort ◽

S. Benton ◽

T. Yu

Keyword(s):

New York ◽

Extracellular Polymeric Substance ◽

Biofilm Formation ◽

Glucuronic Acid ◽

New York State ◽

Immunofluorescence Analysis ◽

Capsule Formation ◽

Polymeric Substance ◽

Cell Substrate ◽

Initial Adhesion

The desmid Penium margaritaceum is a common resident of biofilms of shallow Adirondack wetlands in New York State, USA. It was isolated and grown in the laboratory where it readily formed biofilms and produced large amounts of extracellular polymeric substance (EPS). The EPS was separated into two fractions: an EPS gel and soluble EPS. Both fractions were rich in xylose, fucose and glucuronic acid. The EPS gels contained large amounts of 3-linked, 4-linked and 3,4-linked fucose, 3,4-linked glucuronic acid and terminal xylose linkages. The EPS gel consisted of a fibrillar matrix that linked cells and cell substrate together. Immunofluorescence analysis using an anti-EPS antibody revealed that EPS secretion occurs in several different modes, which contributes to initial adhesion, capsule formation and gliding.

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Optimization of cadmium(II) adsorption onto modified and unmodified lignocellulosics (rice husk and egussi peeling)

International Journal of Basic and Applied Sciences ◽

10.14419/ijbas.v5i1.5195 ◽

2015 ◽

Vol 5 (1) ◽

pp. 45

Author(s):

Tchuifon Tchuifon Donald Raoul ◽

Nche George Ndifor-Angwafor ◽

Ngakou Sadeu Christian ◽

Kamgaing Théophile ◽

Ngomo Horace Manga ◽

...

Keyword(s):

Adsorption Capacity ◽

Rice Husk ◽

Order Kinetic ◽

Adsorption Model ◽

Batch Technique ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Adsorbed Quantity ◽

Minimal Mass ◽

Modified Adsorbents

<p>The present study is based on the adsorption of cadmium (II) ions on rice husk and egussi peeling, unmodified and modified with nitric acid in aqueous solution, using batch technique. It was carried out as a function of contact time, dosage, pH and initial concentration. The equilibrium time was achieved within 25 minutes for unmodified rice husk (Glu NT) and 20 minutes for unmodified egussi peeling (Cuc NT) with an adsorbed quantity of 13.18 mg/g. In the case of modified materials, we obtained 15 minutes for modified rice husk (Glu HNO3) and 10 minutes for modified egussi peeling (Cuc HNO3) with an adsorbed quantity of 18.77 mg/g. The maximum biosorption occurred at pH 5.5 for all biosorbents. The adsorbent mass for maximum adsorption was 0.4 g giving an adsorption capacity of 62.02 % for unmodified adsorbents. In the case of modified adsorbents, the minimal mass at which maximum adsorption occurred was 0.4 g giving an adsorption capacity of 98.33 % and 0.6 g giving an adsorption capacity of 98.33 % for modified rice husk and egussi peeling respectively. The adsorbent/adsorbate equilibrium was well described by the pseudo-second order kinetic model and by Langmuir’s and Freundlich adsorption model. This models showed that the adsorption of cadmium (II) is a chemisorption process.</p>

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FRACTAL PORE STRUCTURE MODEL AND MULTILAYER FRACTAL ADSORPTION IN SHALE

Fractals ◽

10.1142/s0218348x14400106 ◽

2014 ◽

Vol 22 (03) ◽

pp. 1440010 ◽

Cited By ~ 21

Author(s):

LIEHUI ZHANG ◽

JIANCHAO LI ◽

HONGMING TANG ◽

JINGJING GUO

Keyword(s):

Fractal Dimension ◽

Pore Structure ◽

Saturated Vapor ◽

Adsorption Property ◽

Fractal Theory ◽

Complex Structure ◽

Structure Model ◽

Adsorption Model ◽

Adsorption Volume ◽

Isothermal Adsorption

The complex structure and surface property of porous media have significant impact on its accumulation and adsorption capacity. Based on the fractal theory, this paper presents a fractal pore structure model for shales. The effect of different pore structures on fractal dimension is discussed, and the influence of fractal dimension and pore size distribution on porosity is also analyzed. It is shown that the fractal dimension D decreases with the increase of structure parameter q/m for a certain pore diameter ratio, and porosity has positive relationship with fractal dimension. This paper also presents a multilayer fractal adsorption model which takes into account the roughness of adsorption surface by using fractal theory. With the introduction of pseudo-saturated vapor pressure in the supercritical temperature condition, the proposed adsorption model can be applied into a wider range of temperature. Based on the low-pressure nitrogen adsorption and methane isothermal adsorption experiments, the effect of fractal dimension on the adsorption behavior of shales is discussed. Fractal dimension has significant impact on the surface adsorption property and adsorption layer number n. The monolayer saturated adsorption volume Vm increases with the increase of D, while parameter C has the opposite variation trend. Finally, the optimal combination of fractal parameters for describing pore structure of shale samples is selected.

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Performance Evaluation of Small Sized Powdered Ferric Hydroxide as Arsenic Adsorbent

Water ◽

10.3390/w10070957 ◽

2018 ◽

Vol 10 (7) ◽

pp. 957 ◽

Cited By ~ 11

Author(s):

Muhammad Usman ◽

Ioannis Katsoyiannis ◽

Manassis Mitrakas ◽

Anastasios Zouboulis ◽

Mathias Ernst

Keyword(s):

Adsorption Capacity ◽

Tap Water ◽

Ferric Hydroxide ◽

Equilibrium Concentration ◽

Arsenic Species ◽

Batch Adsorption ◽

Order Kinetic ◽

Isothermal Adsorption ◽

Water Matrix ◽

The Impact

The small sized powdered ferric oxy-hydroxide, termed Dust Ferric Hydroxide (DFH), was applied in batch adsorption experiments to remove arsenic species from water. The DFH was characterized in terms of zero point charge, zeta potential, surface charge density, particle size and moisture content. Batch adsorption isotherm experiments indicated that the Freundlich model described the isothermal adsorption behavior of arsenic species notably well. The results indicated that the adsorption capacity of DFH in deionized ultrapure water, applying a residual equilibrium concentration of 10 µg/L at the equilibrium pH value of 7.9 ± 0.1, with a contact time of 96 h (i.e., Q10), was 6.9 and 3.5 µg/mg for As(V) and As(III), respectively, whereas the measured adsorption capacity of the conventionally used Granular Ferric Hydroxide (GFH), under similar conditions, was found to be 2.1 and 1.4 µg/mg for As(V) and As(III), respectively. Furthermore, the adsorption of arsenic species onto DFH in a Hamburg tap water matrix, as well as in an NSF challenge water matrix, was found to be significantly lower. The lowest recorded adsorption capacity at the same equilibrium concentration was 3.2 µg As(V)/mg and 1.1 µg As(III)/mg for the NSF water. Batch adsorption kinetics experiments were also conducted to study the impact of a water matrix on the behavior of removal kinetics for As(V) and As(III) species by DFH, and the respective data were best fitted to the second order kinetic model. The outcomes of this study confirm that the small sized iron oxide-based material, being a by-product of the production process of GFH adsorbent, has significant potential to be used for the adsorptive removal of arsenic species from water, especially when this material can be combined with the subsequent application of low-pressure membrane filtration/separation in a hybrid water treatment process.

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