A new kinetic models analysis for CO adsorption on palladium zeolite nanostructure by roll-coating technique

The aim of this article was the fabrication of Al2O3/Pd(NO3)2/zeolite adsorbent through roll-coating technique for CO gas adsorption. Transmission electron microscopy (TEM), field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), and energy-dispersive x-ray spectroscopy (EDX) were performed to investigate the morphological, structural, and elemental properties of Al2O3/Pd(NO3)2/zeolite adsorbent. A continuous gas analyzer KIMO KIGAZ 210 was applied for testing CO gas adsorption on as-present adsorbent in an experimental set-up. The calculated amounts of adsorption capacity at equilibrium time was 111.16 mg g-1 according to the previous published article. The Elovich, Avrami, and Fractional power kinetic models were studied for this adsorbent. The equal value of experimental and theoretical adsorption capacity at equilibrium time as well as the unit value of regression coefficient indicate that Avrami kinetic model was a suitable model to describe Co removal through Al2O3/Pd(NO3)2/zeolite adsorbent.

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Magnetically Recyclable Wool Keratin Modified Magnetite Powders for Efficient Removal of Cu2+ Ions from Aqueous Solutions

Nanomaterials ◽

10.3390/nano11051068 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1068

Author(s):

Xinyue Zhang ◽

Yani Guo ◽

Wenjun Li ◽

Jinyuan Zhang ◽

Hailiang Wu ◽

...

Keyword(s):

Electron Microscopy ◽

Aqueous Solutions ◽

Adsorption Capacity ◽

Surface Area ◽

Ion Concentration ◽

Bet Surface Area ◽

Chemical Compositions ◽

Ion Adsorption ◽

X Ray ◽

Wool Keratin

The treatment of wastewater containing heavy metals and the utilization of wool waste are very important for the sustainable development of textile mills. In this study, the wool keratin modified magnetite (Fe3O4) powders were fabricated by using wool waste via a co-precipitation technique for removal of Cu2+ ions from aqueous solutions. The morphology, chemical compositions, crystal structure, microstructure, magnetism properties, organic content, and specific surface area of as-fabricated powders were systematically characterized by various techniques including field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), thermogravimetric (TG) analysis, and Brunauer–Emmett–Teller (BET) surface area analyzer. The effects of experimental parameters such as the volume of wool keratin hydrolysate, the dosage of powder, the initial Cu2+ ion concentration, and the pH value of solution on the adsorption capacity of Cu2+ ions by the powders were examined. The experimental results indicated that the Cu2+ ion adsorption performance of the wool keratin modified Fe3O4 powders exhibited much better than that of the chitosan modified ones with a maximum Cu2+ adsorption capacity of 27.4 mg/g under favorable conditions (0.05 g powders; 50 mL of 40 mg/L CuSO4; pH 5; temperature 293 K). The high adsorption capacity towards Cu2+ ions on the wool keratin modified Fe3O4 powders was primarily because of the strong surface complexation of –COOH and –NH2 functional groups of wool keratins with Cu2+ ions. The Cu2+ ion adsorption process on the wool keratin modified Fe3O4 powders followed the Temkin adsorption isotherm model and the intraparticle diffusion and pseudo-second-order adsorption kinetic models. After Cu2+ ion removal, the wool keratin modified Fe3O4 powders were easily separated using a magnet from aqueous solution and efficiently regenerated using 0.5 M ethylene diamine tetraacetic acid (EDTA)-H2SO4 eluting. The wool keratin modified Fe3O4 powders possessed good regenerative performance after five cycles. This study provided a feasible way to utilize waste wool textiles for preparing magnetic biomass-based adsorbents for the removal of heavy metal ions from aqueous solutions.

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Superior Adsorption and Photocatalytic Degradation Capability of Mesoporous LaFeO3/g-C3N4 for Removal of Oxytetracycline

Catalysts ◽

10.3390/catal10030301 ◽

2020 ◽

Vol 10 (3) ◽

pp. 301 ◽

Cited By ~ 2

Author(s):

Ke Xu ◽

Xiaosheng Yang ◽

Luda Ruan ◽

Shaolv Qi ◽

Jianling Liu ◽

...

Keyword(s):

Electron Microscopy ◽

Photocatalytic Degradation ◽

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Thermal Polymerization ◽

X Ray ◽

Practical Applications ◽

Ultrathin Nanosheets ◽

Lafeo3 Nanoparticles ◽

Reheating Process

Mesoporous LaFeO3/g-C3N4 Z-scheme heterojunctions (LFC) were synthesized via the incorporation of LaFeO3 nanoparticles and porous g-C3N4 ultrathin nanosheets. The as prepared LFC were characterized by transmission electron microscopy, scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, powder X-ray diffraction, Raman spectra and N2 adsorption analysis. The structural analysis indicated that the reheating process and the addition of NH4Cl in the thermal polymerization were the key factors to get porous g-C3N4 ultrathin nanosheets and to obtain high specific surface areas of LFC. It remarkably enhanced the adsorption capacity and photocatalytic degradation of LFC for removal of oxytetracycline (OTC). The effect of the mass percentage of LaFeO3 in LFC, pH and temperature on the OTC adsorption was investigated. The LaFeO3/g-C3N4 heterojunction with 2 wt % LaFeO3 (2-LFC) exhibited highest saturated adsorption capacity (101.67 mg g−1) and largest photocatalytic degradation rate constant (1.35 L g−1 min−1), which was about 9 and 5 times higher than that of bulk g-C3N4 (CN), respectively. This work provided a facile method to prepare mesoporous LaFeO3/g-C3N4 heterojunctions with especially well adsorption and photocatalytic activities for OTC, which can facilitate its practical applications in pollution control.

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Fabrication and Characterization of Porous Core–Shell Graphene/SiO2 Nanocomposites for the Removal of Cationic Neutral Red Dye

Applied Sciences ◽

10.3390/app10238529 ◽

2020 ◽

Vol 10 (23) ◽

pp. 8529

Author(s):

Junyi Wang ◽

Tianlu Chen ◽

Biao Xu ◽

Yueqiu Chen

Keyword(s):

Electron Microscopy ◽

Water Vapor ◽

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Neutral Red ◽

Water Vapor Adsorption ◽

Core Shell ◽

X Ray ◽

Adsorption Sites ◽

Sio2 Nanocomposites

Porous rGO/SiO2 nanocomposites with a “core-shell” structure were prepared as an efficient adsorbent for the liquid-phase adsorption of cationic neutral red (NR) dye. The samples were characterized with powder X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TG), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and N2 and water vapor adsorption/desorption methods. The NR removal ability and kinetics of the adsorption process of SiO2 and the rGO/SiO2 nanocomposites were investigated at 298 K. The rGO/SiO2 nanocomposite SG 0.30 showed a superior adsorption of NR dye. In regard to NR at pH 5, we measured a superior adsorption capacity of 66.635 mg/g at an initial NR concentration of 50 mg/L. The experimental adsorption capacity of SG 0.30 was 3.791 times higher than that of SiO2. Then, we compared the results with similar materials used for NR removal. Moreover, the water adsorption sites provided by the nitrogen- and oxygen-containing groups might be one of the reasons for the increased adsorption of water vapor. The broad range of properties of the rGO/SiO2 nanocomposite, including its simple synthesis, ability to be mass prepared, and strong adsorption properties, makes it a truly novel adsorbent that can be industrially produced, and shows potential application in the treatment of wastewater-containing dyes.

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A novel iron modified montmorillonite composite and its enhanced performance for tetracycline hydrochloride adsorption

Functional Materials Letters ◽

10.1142/s1793604719500140 ◽

2019 ◽

Vol 12 (02) ◽

pp. 1950014 ◽

Cited By ~ 3

Author(s):

Wei Yang ◽

Sheng Guo ◽

Jinyi Chen ◽

Abdul Naeem ◽

Hussain Fida ◽

...

Keyword(s):

Electron Microscopy ◽

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Adsorption Process ◽

Interlayer Spacing ◽

Tetracycline Hydrochloride ◽

Maximum Adsorption Capacity ◽

X Ray ◽

Modified Montmorillonite ◽

Wide Ph Range

Iron-modified montmorillonite (Mt) composites with controlled interlayer spacing were successfully synthesized through Fenton-like process with the addition of different concentrations of Rhodamine B (RhB). The physicochemical properties of the resulting samples were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). It was worth noting that the adsorption efficiency of the composite for tetracycline hydrochloride (TC) increased with the increase of the RhB concentration during preparation. The maximum adsorption capacity of the as-prepared composite toward TC was 192.4[Formula: see text]mg/g, which was much higher than that of the Mt (144.9[Formula: see text]mg/g). Moreover, the as-prepared adsorbent showed high adsorption capacity of TC in a wide pH range of 3.0–9.0. The adsorption process followed the pseudo-second-order equation and the Langmuir isotherm model, suggesting the mono-layer chemisorption of the adsorption process. The present work may provide a new strategy for the design and fabrication of functional clay-based materials.

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Synthesis and characterization of highly stoichiometric AgInSe2thin filmsviaa sol–gel spin-coating technique

Journal of Applied Crystallography ◽

10.1107/s002188981203511x ◽

2012 ◽

Vol 45 (5) ◽

pp. 921-925 ◽

Cited By ~ 52

Author(s):

F. A. Al-Agel ◽

Waleed E. Mahmoud

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Spin Coating ◽

Sol Gel ◽

Spin Coating Technique ◽

Spherical Particles ◽

Average Particle ◽

Xps Spectra ◽

X Ray ◽

Coating Technique

Highly stoichiometric AgInSe2thin films have been prepared on a p-type Si(111) substrate by a sol–gel spin-coating technique. These films were annealed at different temperatures. The as-prepared and annealed films were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED) and X-ray photoelectron spectroscopy (XPS). The XRD spectra showed that the crystal structure of the AgInSe2film was that of cubic fluorite chalcopyrite with lattice constantsa= 6.102 Å andc= 11.69 Å. The SEM images depicted the surface morphology as smooth and the spherical particles as uniformly distributed. The average particle size was increased as the annealing temperature increased. Using HRTEM images and SAED patterns for the as-synthesized and annealed thin films, the AgInSe2film was indexed to a pure polycrystalline chalcopyrite AgInSe2structure with a lattice spacing of around 0.3 nm. XPS spectra showed that the as-deposited AgInSe2film was Ag rich, while the AgInSe2films annealed at 523 and 623 K were In rich.

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A comparison of CO2 adsorption behaviour of mono- and diamine-functionalised adsorbents

E3S Web of Conferences ◽

10.1051/e3sconf/20199001010 ◽

2019 ◽

Vol 90 ◽

pp. 01010 ◽

Cited By ~ 3

Author(s):

Noor Ashikin Mohamad ◽

Ebrahim Abouzari Lotf ◽

M. Nasef Mohamed ◽

Ahmad Arshad ◽

TAT Abdullah

Keyword(s):

Electron Microscopy ◽

Adsorption Capacity ◽

Co2 Adsorption ◽

Morphological Changes ◽

Adsorption Behaviour ◽

X Ray Diffraction ◽

X Ray ◽

Co2 Adsorption Capacity ◽

Carbon Dioxide Co2 ◽

Scanning Electron

The paper presents a study for investigating i) the effect of amination of poly(GMA)-grafted polyethylene/polypropylene (PE/PP) substrates with trimethylamine (TMA) and ethylenediamine (EDA) and ii) their impact on carbon dioxide (CO2) adsorption capacity of the obtained adsorbents. The chemical, structural, and morphological changes of the aminated adsorbents were evaluated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM), respectively. The amination yield with TMA was 40% higher than EDA. However, the obtained adsorbent showed two times lower CO2 adsorption capacity (at 30 bars) than the adsorbent with EDA and stood at 0.6 mmol g-1 compared to 1.2 mmol g-1.

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ACID MINE DRAINAGE TREATMENT BY PERLITE NANOMINERAL, BATCH AND CONTINUOUS SYSTEMS

Archives of Mining Sciences ◽

10.2478/amsc-2014-0008 ◽

2014 ◽

Vol 59 (1) ◽

pp. 107-122 ◽

Cited By ~ 1

Author(s):

Kumars Seifpanahi Shabani ◽

Faramarz Doulati Ardejani ◽

Khshayar Badii ◽

Mohammad Ebrahim Olya

Keyword(s):

Electron Microscopy ◽

Acid Mine Drainage ◽

Kinetic Models ◽

Mine Drainage ◽

Fourier Transforms ◽

Order Kinetic ◽

Adsorption Activity ◽

Flow Rates ◽

X Ray ◽

Acid Mine

Abstract In this paper the adsorption activity of perlite nanoparticles for removal of Cu2+, Fe2+ and Mn2+ ions at Iran Sarcheshmeh copper acid mine drainage was discussed. Thus, raw perlite that provided from internal resource was modified and prepared via particles size reduction to nano scale and characterized by X-ray diffraction, X-ray fluorescence, scanning electron microscopy, transmission electron microscopy, Fourier transforms infrared and BET specific surface area analysis. The results of acid mine drainage show that pH of acid mine drainage is 5.1 and Cu2+, Fe2+ and Mn2+ ions are 10.5, 4.1 and 8.3 ppm, respectively. Firstly in the batch system the influence of adsorbent dose and temperature parameters were considered and then isothermal and kinetic models were investigated. According to the results the Langmuir isotherm and pseudo-second order kinetic model showed better correlation with the experimental data than other isotherm and kinetic models. Obtained thermodynamic parameters such as ΔG°, ΔH° and ΔS° show that the Cu2+, Fe2+ and Mn2+ ions adsorption from acid mine drainage is spontaneous and endothermic. Finally, perlite nanoparticles adsorbent was packed inside a glass column and used for the removal of heavy metals in 1, 3, 5 ml/min acid mine drainage flow rates, the breakthrough curves show that the column was saturated at 180, 240 and 315 min for different flow rates, respectively. According to the obtained results, this abundant, locally available and cheap silicate mineral showed a great efficiency for the removal of heavy metal pollutants from acid mine drainage and can be utilized for much volume of acid mine drainage or industrial scale.

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EFFECTS OF ACTIVATED TIME ON STRUCTURAL PROPERTIES OF PLATED PLANT FIBER NONWOVEN SHEETS

Surface Review and Letters ◽

10.1142/s0218625x1850124x ◽

2019 ◽

Vol 26 (01) ◽

pp. 1850124 ◽

Cited By ~ 1

Author(s):

ZHIPING SUN ◽

YAJUN ZHANG ◽

JUNJUN HUANG

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Adsorption Capacity ◽

Structural Properties ◽

Photoelectron Spectroscopy ◽

Saturation Point ◽

Plant Fiber ◽

X Ray ◽

Activating Solution ◽

Scanning Electron

In this work, the effects of activated time on the structural properties of plated plant fiber nonwoven sheet were investigated systematically using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Results showed that there existed a saturated adsorption state on the surface of sheet in the PdCl2 solution. The adsorbed rate and saturated adsorption capacity increased with the increase of PdCl2 concentration. As a result, the deposited quantity and crystallization characteristics of plated nonwoven sheets were firstly enhanced and then unchanged with increase of activated time. The Pd-adsorbed capacity reached saturation point when the activated time was 16[Formula: see text]min. The maximum plated quantity was 0.02 and 0.028[Formula: see text]g/cm2 when the concentration of activating solution was 0.015 and 0.15[Formula: see text]g/L on the surface of sheet.

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Efficient Adsorption of Deoxynivalenol by Porous Carbon Prepared from Soybean Dreg

Toxins ◽

10.3390/toxins13070500 ◽

2021 ◽

Vol 13 (7) ◽

pp. 500

Author(s):

Zhiwei Ying ◽

Di Zhao ◽

He Li ◽

Xinqi Liu ◽

Jian Zhang

Keyword(s):

Electron Microscopy ◽

Specific Surface ◽

Adsorption Capacity ◽

Surface Area ◽

Specific Surface Area ◽

Porous Carbon ◽

Carbon Material ◽

Adsorption Effect ◽

X Ray ◽

Bet Analysis

A novel porous carbon adsorbent for the removal of deoxynivalenol was prepared from soybean dreg (SD). The new material was characterized by scanning electron microscopy equipped with energy dispersive X-ray spectroscopy (SEM-EDS), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) analysis, N2 adsorption/desorption measurement techniques, X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). The specific surface area of the SDB-6-KOH was found to be 3655.95 m2 g−1, the pore volume was 1.936 cm3 g−1 and the average pore size was 2.125 nm. The high specific surface area and effective functional groups of the carbon material promoted the adsorption of deoxynivalenol. By comparing the adsorption effect of SDB-6-X prepared with different activators (X: KOH, K2CO3, KHCO3), SDB-6-KOH had the highest adsorption capacity. The maximum adsorption capacity of SDB-6-KOH to deoxynivalenol was 52.9877 µg mg−1, and the removal efficiency reached 88.31% at 318 K. The adsorption kinetic and isotherm data were suitable for pseudo-second-order and Langmuir equations, and the results of this study show that the novel carbon material has excellent adsorptive ability and, thus, offers effective practical application potential for the removal of deoxynivalenol.

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Acetylene Sensing Characteristics of SnO2 Nanowires

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1119.132 ◽

2015 ◽

Vol 1119 ◽

pp. 132-136

Author(s):

Bing Wang

Keyword(s):

Electron Microscopy ◽

Thermal Evaporation ◽

Gas Adsorption ◽

Gas Sensing ◽

X Ray Diffraction ◽

X Ray ◽

Sensing Material ◽

Transmission Electron ◽

Mems Technology ◽

Sensing Characteristics

SnO2 nanowires have been fabricated using thermal evaporation of the mixed powders of SnO2 and active carbon with Au catalysts. The morphology and structure of the prepared nanowires are determined on the basis of field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectrometer (EDS), x-ray diffraction (XRD) and transmission electron microscopy (TEM). The comb-shape interdigitating electrode made by MEMS technology is used to auxiliary investigating the gas sensing performance of the synthesized SnO2 nanowires. The SnO2 nanowires have sensing response to acetylene concentration of 1000 ppm under operated temperature of 300°C. The gas sensing mechanism is attributed to the gas adsorption and desorption processes occurring on the surface of the gas sensing material.

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