Chitosan-Bentonite Crosslinked Film As Indicator for Copper (II) Ions Adsorption

2021 ◽  
Author(s):  
Nurul Huda Osman ◽  
Nurul Najiha Mazu ◽  
Josephine Liew Ying Chyi ◽  
Muhammad Mahyiddin Ramli ◽  
Mohammad Abdull Halim Mohd Abdull Majid ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Impedance Spectroscopy ◽  
Adsorption Capacity ◽  
Contact Time ◽  
Dc Conductivity ◽  
Dielectric Constants ◽  
Peak Amplitude ◽  
Electrical Parameters ◽  
Before And After

This paper reports on chitosan/bentonite crosslinked (ChB-ECH) film for removal of Cu (II). The effects of chitosan/bentonite ratio on the removal percentage were studied along with the effect of different Cu (II) concentration and the contact time on the film adsorption capacity, qt. The electrical properties of the film are studied, before and after the adsorption occurred, by using impedance spectroscopy for different parameters such as DC conductivity, the complex dielectric constants (ε’ and ε”) and complex electrical modulas (M’ and M’’). The results showed that the chitosan/bentonite ratio of 3:1 produces highest removal percentage at 29 %, while the contact time of 120 minutes was found to be optimum. An increment in the DC conductivity of the ChB-ECH film’s was observed up to 10-7 S/cm as the removal percentage of film increased. The film with the highest Cu (II) adsorb also showed the highest value for ε’ and ε” while exhibiting non-Derby behavior. Shifting of peak amplitude of the M” towards the higher frequency was also observed as the Cu (II) adsorption in the film increased. The results showed that all the electrical parameters can be utilized to determine the amount of adsorbed copper (II) in chitosan/bentonite film.

Evaluation of single cell electrical parameters from bioimpedance of a cell suspension

RSC Advances ◽  
2014 ◽  
Vol 4 (35) ◽  
pp. 18178-18185 ◽  
Author(s):  
Debanjan Das ◽  
Farhan Ahmad Kamil ◽  
Karabi Biswas ◽  
Soumen Das
Keyword(s):  
Electrical Properties ◽  
Impedance Spectroscopy ◽  
Cell Suspension ◽  
Single Cell ◽  
Cost Effective ◽  
Spectroscopy Data ◽  
Electrical Parameters ◽  
Analysis Technique ◽  
A Cell ◽  
Effective Diagnosis

The present study introduces a simple and detailed analysis technique to extract the electrical properties of a single cell from impedance spectroscopy data from a group of cells in suspension, leading to a more reliable and cost effective diagnosis process for disease detection.

Effect of the Thermal Treatment on the Capacity of Removal of Cr (VI) of Sol-Gel Hydrotalcite-like Materials

2012 ◽  
Vol 1372 ◽  
Author(s):  
E. Ramos ◽  
N. L. Gutiérrez ◽  
C. A. Contreras ◽  
G. A. del Angel
Keyword(s):  
Adsorption Capacity ◽  
Contact Time ◽  
Interlayer Space ◽  
Sol Gel ◽  
Textural Properties ◽  
Kinetic Studies ◽  
Before And After ◽  
Short Time ◽  
Thermally Treated

ABSTRACTIn this work the effect on the adsorption of Cr (VI) by thermally treated Hydrotalcite-like Material (HTM) synthesized by the sol-gel method with a Mg/Al = 2 was studied. The characterization of the HTM before and after Cr (VI) removal, as well as the kinetic studies were carried out. When the HTM are thermally treated at 350ºC the hydrotalcite crystalline structure remains and the textural properties improve. The Cr (VI) adsorption capacity of HTM was 125 mg of Cr (VI) / g of HTM. This capacity augments at 132 mg of Cr (VI) / g of HTM after heating HTM at 300°C. The crystallinity as well the porosity of the HTM diminished after adsorption of Cr (VI), due to the obstruction of both the pores and the interlayer space. The adsorption of Cr (VI) occurred before 4 minutes contact time. It can be concluded that HTM exhibits a high Cr (VI) adsorption capacity in a short time.

ADSORPTIVE REMOVAL OF DOXYCYCLINE FROM AQUEOUS SOLUTION USING GRAPHENE OXIDE/HYDROGEL COMPOSITE

2020 ◽  
pp. 100-106
Author(s):  
WALEED K. ABDULSAHIB ◽  
SAFAA H. GANDUH ◽  
MAKARIM A. MAHDI ◽  
LAYTH S. JASIM
Keyword(s):  
Graphene Oxide ◽  
Adsorption Capacity ◽  
Adsorption Kinetics ◽  
Contact Time ◽  
Adsorption Process ◽  
Low Cost ◽  
Hydrogel Composite ◽  
Adsorbent Surface ◽  
Before And After ◽  
Kinetics And Isotherms

Objective: Preparation of novel, safe, and low-cost composite by addition of graphene oxide (GO) to polyvinylpyrrolidone-acrylic acid composite (PVP-AAc) to remove the doxycycline hydrochloride (D) from polluted aquatic environment. Methods: Different concentrations of D were used to study the adsorption process of the antibiotic on the surface of GO/(PVP-AAc) hydrogel composite. The aquatic solution of D was used for studying the adsorption process through a series of different experiments to determine the contact time, adsorbate amount, appropriate temperature, the preferred pH, ionic strength, adsorption kinetics and isotherms on the adsorbent surface of GO/PVP-AAc composite. Fourier transform infrared (FT-IR) spectroscopy and Field-emission scanning electron microscopy (FE-SEM) were used to detect the structure, functional groups and surface morphology of the composite before and after D adsorption. Results: Doxycycline is adsorb on the surface of GO/PVP-AAc hydrogel composite through by physical interactions. The adsorption kinetics correlated to the pseudo-second-order model, contact time studies of D equal to 180 min and the high R2 value of 0.98 indicates that Langmuir isotherm model better fitted to the data for the removal of D at 15 °C. The results of thermodynamic parameters show that the nature of the adsorption process is physical, exothermic, orderly and spontaneous. The adsorption capacity of D favors the acidic media. When NaCl is added to the solution, the adsorption capacity of D will increase. Conclusion: Graphene oxide/PVP-AAc composite is a novel, worthy and efficient adsorbent for the removal of the doxycycline polluted the water because of its low cost, hydrophilic properties, large surface area and special structure that give impressive dispersible activity in aquatic solutions.

Sorption of Bisphenol A in Aqueous Solutions on Irradiated and as-Grown Multiwalled Carbon Nanotubes

2018 ◽  
Vol 69 (5) ◽  
pp. 1233-1239
Author(s):  
Raluca Madalina Senin ◽  
Ion Ion ◽  
Ovidiu Oprea ◽  
Rusandica Stoica ◽  
Rodica Ganea ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Bisphenol A ◽  
Aqueous Solutions ◽  
Adsorption Capacity ◽  
Multiwalled Carbon Nanotubes ◽  
Adsorption Process ◽  
Sorption Process ◽  
Multiwalled Carbon ◽  
Before And After ◽  
Kinetic Sorption

In this study, non-irradiated and weathered multiwalled carbon nanotubes (MWCNTs) obtained through irradiation, were studied as adsorbents for BPA, both nanomaterials being characterized before and after the adsorption process. The objectives of our investigation were to compare the characteristics of non-irradiated and irradiated MWCNTs, to evaluate the adsorption capacity of BPA by pristine and irradiated MWCNTs and to determine the variation of the kinetic, sorption and thermodynamic parameters during sorption process using both sorbents.

Pilot-scale neutralisation of underground mine water

1996 ◽  
Vol 34 (10) ◽  
pp. 141-149 ◽  
Author(s):  
J. P. Maree ◽  
G. J. van Tonder ◽  
P. Millard ◽  
T. C. Erasmus
Keyword(s):  
Mine Water ◽  
Contact Time ◽  
Pilot Scale ◽  
Underground Water ◽  
Underground Mine ◽  
Economic Feasibility ◽  
Fluidised Bed ◽  
Chemical Composition Of Water ◽  
Before And After ◽  
Time Required

Traditionally acid mine water is neutralised with lime (Ca(OH)2). Limestone (CaCO3) is a cheaper alternative for such applications. This paper describes an investigation aimed at demonstrating that underground mine water can be neutralised with limestone in a fluidised-bed. The contact time required between the limestone and the acid water, chemical composition of water before and after treatment, and economic feasibility of the fluidised bed neutralisation process are determined. A pilot plant with a capacity of 10k1/h was operated continuously underground in a gold mine. The underground water could be neutralised effectively using the limestone process. The pH of the water was increased from less than 3 to more than 7, the alkalinity of the treated water was greater than 120 mg/l (as CaCO3) and the contact time required between mine water and limestone was less than 10 min (the exact contact time depends on the limestone surface area). Chemical savings of 56.4% can be achieved compared to neutralisation with lime.

scholarly journals Full Factorial Design for Gold Recovery from Industrial Solutions

Toxics ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 111
Author(s):  
Maria Mihăilescu ◽  
Adina Negrea ◽  
Mihaela Ciopec ◽  
Petru Negrea ◽  
Narcis Duțeanu ◽  
...  
Keyword(s):  
Factorial Design ◽  
Adsorption Capacity ◽  
Contact Time ◽  
Adsorption Process ◽  
Design Method ◽  
Precious Metals ◽  
Gold Recovery ◽  
Maximum Adsorption Capacity ◽  
Gold Concentration ◽  
Commercial Resin

Gold is one of the precious metals with multiple uses, whose deposits are much smaller than the global production needs. Therefore, extracting maximum gold quantities from industrial diluted solutions is a must. Am-L-GA is a new material, obtained by an Amberlite XAD7-type commercial resin, functionalized through saturation with L-glutamic acid, whose adsorption capacity has been proved to be higher than those of other materials utilized for gold adsorption. In this context, this article presents the results of a factorial design experiment for optimizing the gold recovery from residual solutions resulting from the electronics industry using Am-L-GA. Firstly, the material was characterized using atomic force microscopy (AFM), to emphasize the material’s characteristics, essential for the adsorption quality. Then, the study showed that among the parameters taken into account in the analysis (pH, temperature, initial gold concentration, and contact time), the initial gold concentration in the solution plays a determinant role in the removal process and the contact time has a slightly positive effect, whereas the pH and temperature do not influence the adsorption capacity. The maximum adsorption capacity of 29.27 mg/L was obtained by optimizing the adsorption process, with the control factors having the following values: contact time ~106 min, initial Au(III) concentration of ~164 mg/L, pH = 4, and temperature of 25 °C. It is highlighted that the factorial design method is an excellent instrument to determine the effects of different factors influencing the adsorption process. The method can be applied for any adsorption process if it is necessary to reduce the number of experiments, to diminish the resources or time consumption, or for expanding the investigation domain above the experimental limits.

Ionic Conductivities of Doped CeO2 Thin Films as Related to Their Microstructure

1995 ◽  
Vol 411 ◽  
Author(s):  
Chunyan Tian ◽  
Siu-Wai Chan
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Ionic Conductivities ◽  
Dielectric Constants ◽  
Grain Structure ◽  
X Ray Diffraction ◽  
Fine Grain ◽  
Brick Layer Model ◽  
Columnar Grain ◽  
Beam Deposition

ABSTRACTThin films of 4% Y2O3 doped CeO2/Pd film/(001)LaA103 with a very low pinhole density were successfully prepared using electron-beam deposition technique. The microstructure of the films was characterized by x-ray diffraction and the electrical properties were studied as a function of temperature with AC impedance spectroscopy. A brick layer model was adopted to correlate the electrical properties to the microstructure of the films, which can be simplified as either a series or a parallel equivalent circuit associated with either a fine grain or a columnar grain structure, respectively. The conductivities of the films fell between the conductivities derived from the two circuit models, suggesting that the films are of a mixed fine grain and columnar grain structure. The measured dielectric constants of the films were found smaller than that of the bulk.

Electrical properties of (Cu1-xAgx)7GeS5I crystals investigated by impedance spectroscopy

2021 ◽  
Vol 363 ◽  
pp. 115593
Author(s):  
V. Kavaliukė ◽  
T. Šalkus ◽  
S. Balčiūnas ◽  
J. Banys ◽  
A.I. Pogodin ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Impedance Spectroscopy

scholarly journals Channel Impulse Response at 60 GHz and Impact of Electrical Parameters Properties on Ray Tracing Validations

Electronics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 393
Author(s):  
Huthaifa Obeidat ◽  
Atta Ullah ◽  
Ali AlAbdullah ◽  
Waqas Manan ◽  
Omar Obeidat ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Ray Tracing ◽  
Impulse Response ◽  
Line Of Sight ◽  
Indoor Propagation ◽  
60 Ghz ◽  
Environment Design ◽  
Electrical Parameters ◽  
Concrete Walls ◽  
Properties Of Materials

This paper outlines a study of the effect of changing the electrical properties of materials when applied in the Wireless InSite (WI) ray-tracing software. The study was performed at 60 GHz in an indoor propagation environment and supported by Line of Sight (LoS) and Non-LoS measurements data. The study also investigates other factors that may affect the WI sensitivity, including antenna dimensions, antenna pattern, and accuracy of the environment design. In the experiment, single and double reflections from concrete walls and wooden doors are analysed. Experimental results were compared to those obtained from simulation using the WI. It was found that materials selected from the literature should be similar to those of the environment under study in order to have accurate results. WI was found to have an acceptable performance provided certain conditions are met.

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