scholarly journals Enhanced decontamination of levofloxacin as toxic pharmaceutical residuals from water using CaO/MgO nanorods as a promising adsorbent

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Mostafa R. AbuKhadra ◽  
Mohamed Gameel Basyouny ◽  
Ali A. AlHammadi ◽  
Ahmed M. El-Sherbeeny ◽  
Mohamed Abdel Salam
Keyword(s):  
Ph Value ◽  
Average Particle Size ◽  
Kinetic Studies ◽  
Bet Surface Area ◽  
Average Particle ◽  
Uptake Capacity ◽  
Equilibrium Studies ◽  
Monolayer Adsorption ◽  
Chi Squared ◽  
Remediation Process

Abstract Novel MgO/CaO nanocomposite (MgO/CaO NRs) was synthesized by the hydrothermal method using diatomite porous frustules as a substrate under the microwave irradiation. The composite appeared as well crystalline rod-like nanoparticles with 52.3 nm as average particle size and 112.8 m2/g as BET surface area. The synthetic MgO/CaO NRs were addressed as a novel adsorbent for promising removal of levofloxacin (LVX) as pharmaceutical residuals. The adsorption studies revealed effective uptake of levofloxacin by MgO/CaO NRs with theoretical qmax of 106.7 mg/g and the equilibrium time of 720 min considering the best pH value (pH 7). The equilibrium studies highly fitted with the Langmuir model of monolayer adsorption considering the values of Chi-squared (χ2) and determination coefficient. The estimated adsorption energy from Dubinin–Radushkevich (0.2 kJ/mol) signifies physisorption mechanisms that might be coulombic attractive forces considering the kinetic studies. The thermodynamic addressing for the reactions verified their spontaneous and exothermic nature within a temperature range from 303 to 333 K. Additionally, the prepared MgO/CaO NRs show significant recyclability properties to be used in realistic remediation process and its uptake capacity is higher than several studied adsorbents in literature.

scholarly journals Description, Kinetic and Equilibrium Studies of the Adsorption of Carbon Dioxide in Mesoporous Iron Oxide Nanospheres

2021 ◽  
Vol 12 (1) ◽  
pp. 1022-1038
Keyword(s):  
Iron Oxide ◽  
High Efficiency ◽  
Co2 Adsorption ◽  
Average Particle Size ◽  
Bet Surface Area ◽  
Average Particle ◽  
Equilibrium Studies ◽  
Spherical Form ◽  
Best Fit

Mesoporous iron oxide nanospheres (MINs) have been successfully synthesized and have proven to be high-efficiency adsorbents. The morphology of the MINs is very uniform in spherical form, with an average particle size of 23-27 nm in the diameter range. MINs content has a fairly high BET surface area of 188.25 m2g−1 and a total volume of 0.14 cm3g−1 pores. Thus, seams were seen as potential CO2 sequestration reservoirs to reduce greenhouse gas emissions. The CO2 adsorption was favorable at low temperature and dry MINs conditions. However, MINs have a high adsorption capacity of 0.15 mmol/g. The CO2 adsorption isotherm of all coal samples according to the IUPAC classification of adsorption isotherms fits category I, which most likely explains adsorption confined to a few layers of molecules (micropores and mesopores). The balancing assessment using Langmuir, Henry, Dubbin, Temkin, Toth, Harkins-Jura, Elovich, Redlich-Peterson, and Josene model provided the best fit for any experimental adsorption data that predict heterogeneous surface properties of MINs.

scholarly journals Commercial Cokes and Graphites as Anode Materials for Lithium - Ion Cells

1997 ◽  
Vol 496 ◽  
Author(s):  
David J. Derwin ◽  
Kim Kinoshita ◽  
Tri D. Tran ◽  
Peter Zaleski
Keyword(s):  
Electron Microscopy ◽  
Ethylene Carbonate ◽  
Average Particle Size ◽  
Chemical Properties ◽  
Lithium Ion ◽  
Reversible Capacity ◽  
Bet Surface Area ◽  
Average Particle ◽  
Electrochemical Characteristics ◽  
Wide Range

AbstractSeveral types of carbonaceous materials from Superior Graphite Co. were investigated for lithium ion intercalation. These commercially available cokes, graphitized cokes and graphites have a wide range of physical and chemical properties. The coke materials were investigated in propylene carbonate based electrolytes and the graphitic materials were studied in ethylene carbonate / dimethyl solutions to prevent exfoliation. The reversible capacities of disordered cokes are below 230 mAh / g and those for many highly ordered synthetic (artificial) and natural graphites approached 372 mAh / g (LiC6). The irreversible capacity losses vary between 15 to as much as 200 % of reversible capacities for various types of carbon. Heat treated cokes with the average particle size of 10 microns showed marked improvements in reversible capacity for lithium intercalation. The electrochemical characteristics are correlated with data obtained from scanning electron microscopy (SEM), high resolution transmission electron microscopy (TAM), X - ray diffraction (XRD) and BET surface area analysis. The electrochemical performance, availability, cost and manufacturability of these commercial carbons will be discussed.

scholarly journals Olive Leaves as Biotemplates for Enhanced Solar-Light Harvesting by a Titania-Based Solid

Nanomaterials ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1057
Author(s):  
Jesús Hidalgo-Carrillo ◽  
Juan Martín-Gómez ◽  
M. Carmen Herrera-Beurnio ◽  
Rafael C. Estévez ◽  
Francisco J. Urbano ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Electron Paramagnetic Resonance Spectroscopy ◽  
Average Particle Size ◽  
Solar Irradiation ◽  
Bet Surface Area ◽  
Resonance Spectroscopy ◽  
Average Particle ◽  
Olive Leaves ◽  
Sem Images ◽  
X Ray

Olive leaves (by-product from olive oil production in olive mills) were used as biotemplates to synthesize a titania-based artificial olive leaf (AOL). Scanning electron microscopy (SEM) images of AOL showed the successful replication of trichomes and internal structure channels present in olive leaves. The BET surface area of AOL was 52 m2·g−1. X-ray diffraction (XRD) and Raman spectra revealed that the resulting solid was in the predominantly-anatase crystalline form (7.5 nm average particle size). Moreover, the synthesis led to a red-shift in light absorption as compared to reference anatase (gap energies of 2.98 and 3.2 eV, respectively). The presence of surface defects (as evidenced by X-ray photoelectron spectroscopy, XPS, and electron paramagnetic resonance spectroscopy, EPR) and doping elements (e.g., 1% nitrogen, observed by elemental analysis and XPS) could account for that. AOL was preliminarily tested as a catalyst for hydrogen production through glycerol photoreforming and exhibited an activity 64% higher than reference material Evonik P25 under solar irradiation and 144% greater under ultraviolet radiation (UV).

scholarly journals SiO2:MgMnO3: An Efficient Heterogeneous Catalyst for One Pot Synthesis of 1H-Pyrazolo[1,2-b]phthalazine-5,10-dione Derivatives

2020 ◽  
Vol 32 (10) ◽  
pp. 2489-2494
Author(s):  
S.S. Sagar ◽  
R.P. Chavan
Keyword(s):  
Surface Area ◽  
Average Particle Size ◽  
Bet Surface Area ◽  
High Yield ◽  
Average Particle ◽  
One Pot ◽  
Short Reaction Time ◽  
Investigative Techniques ◽  
Current Procedure ◽  
Efficient Heterogeneous Catalyst

The present study deals with hydrothermal synthesis of SiO2 composite MgMnO3 catalyst. The obtained polycrystalline product was analyzed by using physical investigative techniques including XRD, SEM, EDAX, TEM, SAED and BET surface area. The product corresponded to average particle size of 100 nm by TEM images. The BET surface area was found 234.38 cm2/g for SiO2 composite MgMnO3 catalyst which indicates a good catalytic property. The synthesized catalyst was applied for the synthesis of 1H-pyrazolo[1,2-b]-phthalazine-5,10-dione in presence of ethanol as a solvent at 80 ºC. The current procedure and catalyst offers the gains of clean reaction, short reaction time, high yield, easy purification and financial availability of the catalyst.

scholarly journals Isothermal models of Chromium (VI) adsorption by using Fe3O4 nanoparticles

10.30544/489 ◽  
2020 ◽  
Author(s):  
Dang Tan Hiep ◽  
Bui Thi Hoa ◽  
Ngo Thi My Thanh ◽  
Nguyen Viet Long ◽  
Le Hong Phuc ◽  
...  
Keyword(s):  
Fe3o4 Nanoparticles ◽  
Contact Time ◽  
Ph Value ◽  
Average Particle Size ◽  
Adsorption Kinetic ◽  
Average Particle ◽  
Suitable Model ◽  
Isothermal Adsorption ◽  
Adsorption Models ◽  
Chromium Vi

The ferromagnetic Fe3O4 nanoparticles with the average particle size of about 10 nm were used to adsorb chromium (VI) in aqueous solution. The equilibrium of Cr(VI) adsorption can be achieved at the pH value of 2.5, in the contact time of 120 minutes. The mechanisms of Cr(VI) adsorption were evaluated by 4 isothermal adsorption models Langmuir, Freundlich, Redlich-Peterson, and Temkin. The results showed that all four models are satisfied; especially, Redlich-Peterson is the most suitable model to describe the adsorption kinetic of Cr(VI) on ferromagnetic Fe3O4 nanoparticles.

Selection of Polyanions as Complexation Agent in the Formation of Nanochitosan by Polyelectrolyte Complex Method

2019 ◽  
Vol 948 ◽  
pp. 140-145
Author(s):  
Al Dina N. Khoerunisa ◽  
Prihati Sih Nugraheni ◽  
Mohammad Fahrurrozi ◽  
Wiratni Budhijanto
Keyword(s):  
Particle Size ◽  
Polyelectrolyte Complex ◽  
Ph Value ◽  
Average Particle Size ◽  
Aqueous Dispersion ◽  
Complex Method ◽  
Average Particle ◽  
Arabic Gum ◽  
Mixing Ratios ◽  
The Stability

The aqueous dispersion of nanochitosan was prepared by polyelectrolyte complex (PEC) method with various mixing ratios of chitosan and polyanions, i.e., chitosan-glucomannan, chitosan-hyaluronic acid, and chitosan-Arabic gum. The formation of nanochitosan was carried out by adding the polyanion solution dropwise into the acid solution of chitosan. The study aimed to determine the best polyanion among the variations tested in this study, concerning the targeted particle size and the stability of the dispersion over time. Particle size distribution was observed by Particle Size Analyzer (PSA). The result indicated that Arabic gum gave the smallest average particle size, i.e. 192.5 nm, at a chitosan/polyanion mass ratio of 3:1 and pH value of 4.

Development of Heterostructured Ferroelectric SrZrO3/CdS Photocatalysts with Enhanced Surface Area and Photocatalytic Activity

2020 ◽  
Vol 20 (6) ◽  
pp. 3770-3779 ◽  
Author(s):  
Umar Farooq ◽  
Farheen Naz ◽  
Ruby Phul ◽  
Nayeem Ahmad Pandit ◽  
Sapan Kumar Jain ◽  
...  
Keyword(s):  
Particle Size ◽  
Dielectric Constant ◽  
Photocatalytic Activity ◽  
Surface Area ◽  
Room Temperature ◽  
Average Particle Size ◽  
Chemical Deposition ◽  
Bet Surface Area ◽  
Cds Nanoparticles ◽  
Average Particle

This paper reports the attempt to develop an efficient heterostructure photocatalyst by employing SrZrO3 as ferroelectric substrate with deposited nanostructured CdS semiconductor on the surface. Primarily bare SrZrO3 and CdS nanoparticles were synthesized by using polymeric citrate precursor and co-precipitation routes, respectively. The chemical deposition technique was used to develop the CdS over the surface of the pre-synthesized SrZrO3 nanoparticles. The synthesized bare nanoparticles and their heterostructure were characterized by XRD which shows the formation of orthorhombic and face centred cubic (FCC) phases of SrZrO3 and CdS, respectively. TEM was used to estimate the morphology and particle size of as-synthesized nanoparticles, which shows the average particle size of 14, 24 and 25 nm for SrZrO3, CdS and SrZrO3/CdS, respectively. The BET surface area of SrZrO3, CdS and SrZrO3/CdS samples was found to be 299, 304 and 312 m2/g respectively. Methylene blue was used as model pollutant to determine the photocatalytic activity of the synthesized nanomaterials. The heterostructure shows an enhanced activity as compared to bare nanoparticles. Dielectric constant and dielectric loss of the nanoparticles was investigated as a function of frequency at room temperature and as a function of temperature at 500 kHz. The room temperature dielectric constant for SrZrO3, CdS and SrZrO3/CdS was found to be 13.2, 17.8 and 25.5 respectively at 100 kHz.

Preparation and Performance of Mesoporous TiO2 Photocatalyst with P123 as Template

2016 ◽  
Vol 680 ◽  
pp. 198-202
Author(s):  
Chao Wang ◽  
Si Qin Zhao ◽  
S. Asuha
Keyword(s):  
Particle Size ◽  
Photocatalytic Activity ◽  
Degradation Rate ◽  
Average Particle Size ◽  
Bet Surface Area ◽  
Average Particle ◽  
Hydrothermal Time ◽  
Hydrothermal Temperature ◽  
Type Iv ◽  
And Performance

In this paper, a series of mesoporous TiO2 photocatalyst were prepared by hydrothermal method using block copolymer P123 as template and Ti (OBu)4 as titanium source. The microstructure and spectroscopy performance of the prepared TiO2 were characterized by means of XRD, SEM, TEM, BET, and BJH analysis, and the photocatalytic activity of mesoporous TiO2 were examined by measuring the photodegradation of methyl orange , then discussed the best prepared conditions of mesoporous TiO2 photocatalyst. The results showed that the products were all anatase mesoporous TiO2 nanopowder, the average particle size is about 7nm and all have the Langmuir type IV pore structure. The best prepared condition: hydrothermal temperature is 160°C, hydrothermal time is 24h, mesoporous TiO2 photocatalyst has the BET surface area of 146m2/g , it’s photocatalytic degradation rate is 97.07% in an hour.

Ce Basic Hydroxycarbonate Complexe as Precursor for Mesoporous Ceria: Synthesis and Characterization

2007 ◽  
Vol 121-123 ◽  
pp. 97-100
Author(s):  
D. Yang ◽  
Ming Fen Wen ◽  
Ch.L. Song ◽  
Jian Chen ◽  
Yong Wan Gu
Keyword(s):  
Particle Size ◽  
Pore Structure ◽  
Average Particle Size ◽  
High Thermal Stability ◽  
Bet Surface Area ◽  
Synthesis And Characterization ◽  
Hexadecyltrimethylammonium Bromide ◽  
Average Particle ◽  
Mesoporous Ceo2 ◽  
20 Nm

Herein mesoporous CeO2 with high thermal stability was synthesized via a new hydroxycarbonates based hydrothermal threatment approach in present of hexadecyltrimethylammonium bromide (CTAB). IR and XRD prove the coexistence of hydroxycarbonate cerium and CTAB in precursors. TEM micrographs show that non-ordered pore structure is formed in the product, and average particle size of 20 nm is obtained even after calcined at 1173 K. BET results exhibit that the pore structure is stable when the calcination temperature is below 923 K. However, While calcinated at 1173 K, the average particle size is 20 nm, the BET surface area and pore volume can remain as high as 31.07 m2/g and 0.21 cm3 g-1.

scholarly journals Dry Reforming of Methane Using Ni Catalyst Supported on ZrO2: The Effect of Different Sources of Zirconia

Catalysts ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 827
Author(s):  
Ahmed Aidid Ibrahim ◽  
Anis Hamza Fakeeha ◽  
Ahmed Elhag Abasaeed ◽  
Ahmed Sadeq Al-Fatesh
Keyword(s):  
Supported Catalysts ◽  
Average Particle Size ◽  
Cost Effective ◽  
Dry Reforming ◽  
Dry Reforming Of Methane ◽  
Bet Surface Area ◽  
Ni Catalyst ◽  
Average Particle ◽  
Tem Analysis ◽  
Different Sources

Dry reforming of methane (DRM) has a substantial potential to provide a cost-effective process and in reducing greenhouse gases. Its application has been hindered by carbon deposition and instability problems. The use of an appropriate catalyst is influenced by the support type. The objective of this investigation is to elucidate the effect of different sources of ZrO2 support. Four kinds of ZrO2, namely RC-100 and Z-3215, MKnano, and ELTN were acquired from Japan, Canada, and China, respectively. The catalyst samples were analyzed by BET, XRD, TPR, TPD, TEM, TGA, TPO, FT-IR, and Raman. The analysis of the structural properties displayed that all Ni-supported catalysts, regardless of their source, are mesoporous and that 5Ni-RC-100 possessed the highest BET surface area of 17.7 m2/g and 5Ni-MKnano had the lowest value of BET 3.16 m2/g. In the TPD and TEM analysis, the 5Ni-RC-100 catalyst presented the highest intensity of basicity and the minimum average particle size of 3.35 nm, respectively. The 5Ni-RC-100 catalyst outperformed 5Ni-ELTN by exhibiting 44% higher CH4 conversion; however, 5Ni-RC-100 gave the highest weight loss in the TGA analysis of 66%.

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