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

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.

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Low-Temperature Adsorption Study of Carbon Dioxide on Porous Magnetite Nanospheres Iron Oxide

Biointerface Research in Applied Chemistry ◽

10.33263/briac125.62526268 ◽

2021 ◽

Vol 12 (5) ◽

pp. 6252-6268

Keyword(s):

Adsorption Isotherms ◽

High Efficiency ◽

Co2 Adsorption ◽

Average Particle Size ◽

Total Pore Volume ◽

Spherical Shape ◽

Bet Surface Area ◽

Average Particle ◽

Type I ◽

Magnetite Fe3o4

Porous magnetite Fe3O4 nano-spheres (PMNs) have been successfully produced and have been demonstrated to be high-efficiency adsorbents. The PMNs have a spherical shape with an average particle size of 25.84 nm. The BET surface area of PMNs is 143.65 m2g-1, with a total pore volume of 0.16 cm3g-1. As a result of CO2 adsorption and desorption features on dry PMNs, this synthesized material is projected to be exploited as possible CO2 sequestration reservoirs to minimize greenhouse gas emissions. CO2 adsorption was best at low temperatures and with dry PMNs. PMNs, on the other hand, has a very high adsorption capacity of 0.96 mmol/g. According to the IUPAC categorization of adsorption isotherms, all CO2 adsorption isotherms of coal samples fall into type I, which most likely indicates adsorption restricted to a few layers of molecules (micropores and mesopores). Langmuir, Henry, Dubbin, Temkin, Toth, Harkin-Jura, Elovich, Redlich Peterson, and Josene models suit any experimental adsorption data that best predict the heterogeneous surface features of PMNs.

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

Scientific Reports ◽

10.1038/s41598-020-71951-6 ◽

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.

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

MRS Proceedings ◽

10.1557/proc-496-575 ◽

1997 ◽

Vol 496 ◽

Cited By ~ 1

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.

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

Nanomaterials ◽

10.3390/nano10061057 ◽

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).

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

Asian Journal of Chemistry ◽

10.14233/ajchem.2020.22707 ◽

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.

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PENGARUH LAJU PREKURSOR SERBUK ALUMINIUM TERHADAP BENTUK MORFOLOGI NANOPARTIKEL ALUMINA DENGAN METODE THERMAL PLASMA

ROTOR ◽

10.19184/rotor.v10i1.5142 ◽

2017 ◽

Vol 10 (1) ◽

pp. 17

Author(s):

Havid Arifian Rochman ◽

Arief Ginanjar Dirgantara ◽

Salahudin Junus ◽

Imam Sholahuddin ◽

Aris Zainul Muttaqin

Keyword(s):

Particle Size ◽

Aluminum Powder ◽

Thermal Plasma ◽

High Efficiency ◽

Average Particle Size ◽

Alumina Nanoparticles ◽

Rate Variation ◽

Average Particle ◽

Dc Plasma ◽

Simple Method

The synthesis of nanoparticles using thermal DC plasma method is a simple method for ease of installation and high efficiency is due to the rate of precursor that can be controlled. Micro-sized aluminum powder is synthesized using thermal DC plasma undergoing a process of evaporation as it passes through high temperature plasma flame, where kemuadian oxidized aluminum particles which evaporates the particles are split and binds with oxygen to form aluminum oxide or also known as alumina (Al2O3). In this experiment, the flow rate of oxygen plasma parameters at 35 SCFH (Standard Cubic Feet per Hour) and 20 amperes flows with precursors rate variation of 1.16 g / min, 3.19 g / min, and 3.5 g / min. Precursors used is 88 micro sized aluminum powder. To determine the morphology of nanoparticles of alumina testing scanning electron microscopy (SEM), the morphology form of nanosphere. Results of the analysis showed that the rate of precursor low causing agglomeration level slightly while the higher rate of precursor agglomeration rate also increased. At the rate of precursor 1.16 g / min, nanoparikel undergo agglomeration with an average particle size of 36.55 nm, and then at a rate of 3.19 gr precursor / mnt an average particle size of 46.49 nm, and at a rate of 3.5 gr / mnt an average particle size of 46.49 nm. The powder nanoparticles were then characterized using X-ray defraksi (XRD) where all alumina nanoparticles were synthesized showed alumina phase that is formed is a phase δ-Al2O3. Keywords: Alumina nanoparticles, DC Thermal Plasma, morphology, precursor rate, nanoparticles size, SEM, XRD.

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Effect of Concentration of Iron Oxide on Crystallization Behavior in Leadless Iron Oxide Crystalline Glaze

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.554-556.18 ◽

2012 ◽

Vol 554-556 ◽

pp. 18-22

Author(s):

Supakorn Silakate ◽

Anucha Wannagon ◽

Apinon Nuntiya

Keyword(s):

Iron Oxide ◽

Nepheline Syenite ◽

Crystallization Behavior ◽

Raw Materials ◽

Average Particle Size ◽

Average Particle ◽

Oxide Content ◽

Iron Oxide Content ◽

X Ray Diffraction ◽

X Ray

The objectives of this study were to prepare leadless crystalline glazes from iron oxide by using low temperature firing (1,100°C) and to study the effect of concentration of iron oxide on the phase composition of the glaze raw materials on phase transformation in leadless iron oxide crystalline glaze. The crystalline phases were investigated by using the DTA, X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The composition of the glaze raw materials compose of nepheline syenite, colemanite, pottery stone, bentonite, ZnO, Li2CO3, SiOSubscript text2 and 10, 15 and 20%(w/w) iron oxide (Fe2O3). The glaze raw materials were ground for homogeneous mixtures by ball milling for 24h. The average particle size of the mixture was 3.86 µm. The glaze bodies were carried to firing at 1,100°C at the heating rate of 2°C/min and soaking for 0.5h. Then, the glaze bodies were cooled at the cooling rate of 1°C/min and maintained at 1,080°C for 3h and then maintained at 980°C for 1h, respectively. From the experiment results, it was found that the crystallization temperatures (Tc) of franklinite (ZnFe2O4) and anorthite (CaAl2Si2O8) depend on the concentration of iron oxide content.

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Reinforcement of Quaternary Ammonium Modified Silica (QAMS) with Magnetite and its Application by Solid Phase Adsorption (SPA) to Adsorb Chromate Ions

Jurnal Kimia Sains dan Aplikasi ◽

10.14710/jksa.23.10.338-345 ◽

2020 ◽

Vol 23 (10) ◽

pp. 338-345

Author(s):

Ngatijo Ngatijo ◽

Restina Bemis ◽

Abdul Aziz ◽

Rahmat Basuki

Keyword(s):

Solid Phase ◽

Average Particle Size ◽

Xrd Analysis ◽

Average Particle ◽

Modified Silica ◽

Spherical Form ◽

Chromate Ions ◽

Chromium Vi ◽

The Stability ◽

Ph Range

Chromium (VI) in the form of chromate anions that have toxic properties needs to be overcome. This study aims to reinforce cationic sorbent quaternary amine-modified silica with magnetite (QAMS-Fe3O4) to adsorb chromate ions. QAMS prepared by reflux methylation ammine modified silica (AMS) obtained from destruction silicate from rice husk ash followed by the addition of 3-APTMS. Characterization QAMS-Fe3O4 by FT-IR showed successfully of methylation process indicated by disappearing absorbance at 1388 cm-1, and emerging absorbance at 2939 cm-1 in QAMS and QAMS-Fe3O4 indicated a transformation of N-H from -NH2 group to [-N+(CH3)3]. XRD analysis denotes 2θ = 30.15°, 35.53°, 43.12°, 57.22°, and 62.90° (JCPDS No. 00-033-0664) fathomed as a characteristic peak of magnetite. SEM-EDX reveals the homogenous topological spherical form with an average particle size 0.006 µm that is dominated by Si element (52.81%) with magnetic moment value = 34.1 emu/g. The stability test shows that this material stable in an acid condition. The adsorption of chromate ions was conducted by the SPA method. Optimal pH obtained by pH range 4-7 with more than 90% adsorbed chromate ions. Variation of increasing series flow rate from 0.05 to 1.5 mL min-1 resulted in decreased adsorbed chromate ions. The use of SPA methods offered simpler and easier handling than the batch method without overriding the adsorption process effectiveness.

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A New Collector for Effectively Increasing Recovery in Copper Oxide Ore-Staged Flotation

Minerals ◽

10.3390/min9100595 ◽

2019 ◽

Vol 9 (10) ◽

pp. 595

Author(s):

Renfeng Zhu ◽

Guohua Gu ◽

Zhixiang Chen ◽

Yanhong Wang ◽

Siyu Song

Keyword(s):

Particle Size ◽

Copper Oxide ◽

High Efficiency ◽

Average Particle Size ◽

Economic Feasibility ◽

Processing Plant ◽

Average Particle ◽

Entrainment Rate ◽

Flotation Process ◽

New Type

A new method, staged flotation for effectively increasing the recovery of ultra-fine copper oxide ore with a new type of collector (ZH-1, C3-5 carbon chain xanthate) is proposed for the first time. The flotation process and mechanism were examined by flotation tests, entrainment rate analysis, laser particle size experiments and microscopic imagery as well as economic feasibility analysis. It was demonstrated that the collector isoamyl sodium xanthate (ISX) shows a good collection ability (recovery exceeded 95%) for azurite, but the recovery was relatively much lower for malachite (only near 80%) due to the different particle size distribution. The new type of xanthate ZH-1 has shown a high-efficiency collection performance for fine-grained malachite. The recovery achieved for −10 μm malachite was more than 95% when the ZH-1 dosage was 150 mg/L, while the average particle size of −10 μm malachite sharply increased from 4.641 μm to 9.631 μm. The batch flotation results indicated that the copper oxide flotation recovery increased from 79.67% to 83.38%, and the grade also raised from 18.08% to 18.14% after using the staged flotation technology with ZH-1 as collector during the flotation of −25 μm ore. It was confirmed that this technology was quite effective for the recovery of copper oxide at the Dishui Copper Processing Plant, which successfully increased its gross profit by 1.6 million US$ per year.

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

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17516 ◽

2020 ◽

Vol 20 (6) ◽

pp. 3770-3779 ◽

Cited By ~ 6

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.

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