scholarly journals Novel Functionality of Lithium-Impregnated Titania as Nanocatalyst

Catalysts ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 943
Author(s):  
Indu Ambat ◽  
Varsha Srivastava ◽  
Esa Haapaniemi ◽  
Mika Sillanpää
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Acid Methyl Ester ◽  
Optical Emission ◽  
Waste Cooking Oil ◽  
Catalytic Performance ◽  
Physical Parameters ◽  
Lithium Ions ◽  
13C Nuclear Magnetic Resonance ◽  
Bet Analysis

The present work incorporates the synthesis of a multifunctional catalyst for the transesterification of waste cooking oil (WCO) to biodiesel and recovery of rare earth elements (REEs). For this purpose, TiO2 nanoparticles and TiO2 doped with lithium ions were prepared. The influence of lithium ions on the catalytic performance of TiO2 was attained by impregnation of the different molar ratios of lithium hydroxide to bare TiO2. Then each catalyst was screened for catalytic conversion of WCO to fatty acid methyl ester (FAME) and also for REEs recovery. All synthesized materials were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), Transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) analysis, and Hammett indicator for the basicity test. The obtained biodiesel was characterized by gas chromatography with mass spectrometry (GC-MS), 1H, and 13C nuclear magnetic resonance (NMR). Moreover, the physical parameters of the synthesized biodiesel were also determined. The REEs recovery efficiency of synthesized nanomaterials was investigated, and the percentage of REEs removal was determined by inductively-coupled plasma optical emission spectroscopy (ICP-OES).

scholarly journals The Effect of Mg and Zn Dopants on Pt/Al2O3 for the Dehydrogenation of Perhydrodibenzyltoluene

Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 490
Author(s):  
Rudaviro Garidzirai ◽  
Phillimon Modisha ◽  
Innocent Shuro ◽  
Jacobus Visagie ◽  
Pieter van Helden ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Flow Reactor ◽  
Plug Flow ◽  
Optical Emission ◽  
Catalytic Performance ◽  
Emission Spectrometry ◽  
Hydrogen Yield ◽  
X Ray ◽  
Temperature Programmed

The effects of Mg and Zn dopants on the catalytic performance of Pt/Al2O3 catalyst were investigated for dehydrogenation of perhydrodibenzyltoluene (H18-DBT) as a liquid organic hydrogen carrier. Al2O3 supports were modified with Mg and Zn to produce Mg-Al2O3 and Zn-Al2O3 with a target loading of 3.8 wt.% for dopants. The modified supports were impregnated with chloroplatinic acid solution to produce the catalysts Pt/Al2O3, Pt/Mg-Al2O3 and Pt/Zn-Al2O3 of 0.5 wt.% Pt loading. Thereafter, the catalysts were characterised using inductively coupled plasma- optical emission spectrometry, scanning electron microscopy-energy dispersive X-ray spectroscopy, hydrogen temperature-programmed reduction, carbon-monoxide pulse chemisorption, ammonia temperature-programmed desorption, X-ray diffraction and transmission electron microscopy. The dehydrogenation experiments were performed using a horizontal plug flow reactor system and the catalyst time-on-stream was 22 h. Pt/Mg-Al2O3 showed the highest average hydrogen flowrate of 29 nL/h, while an average of 27 nL/h was obtained for both Pt/Al2O3 and Pt/Zn-Al2O3. This has resulted in a hydrogen yield of 80% for Pt/Mg-Al2O3, 71% for Pt/Zn-Al2O3 and 73% for Pt/Al2O3. In addition, the conversion of H18-DBT ranges from 99% to 92%, Pt 97–90% and 96–90% for Pt/Mg-Al2O3, Pt/Zn-Al2O3 and Pt/Al2O3, respectively. Following the latter catalyst order, the selectivity to dibenzyltoluene (H0-DBT) ranges from 78% to 57%, 75–51% and 71–45%. Therefore, Pt/Mg-Al2O3 showed improved catalytic performance towards dehydrogenation of H18-DBT.

scholarly journals A Study of Vanadate Group Substitution into Nanosized Hydroxyapatite Doped with Eu3+ Ions as a Potential Tissue Replacement Material

Nanomaterials ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 77
Author(s):  
Nicole Nowak ◽  
Rafal Jakub Wiglusz
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Dermal Fibroblast ◽  
Emission Spectra ◽  
Optical Emission ◽  
Precipitation Method ◽  
Ion Release ◽  
Normal Human Dermal Fibroblast ◽  
Excitation Spectra ◽  
Average Grain Size

In this study, nanosized vanadate-substituted hydroxyapatites doped with 1 mol% and 2 mol% Eu3+ ions were obtained via the precipitation method. To evaluate the structure and morphology of the obtained compounds, the XRPD (X-ray powder diffraction) technique, Rietveld refinement, SEM-EDS (scanning electron microscopy-energy-dispersive spectrometry) and TEM (transmission electron microscopy) techniques as well as FTIR (Fourier transform infrared) spectroscopy were performed. Moreover, the chemical formula was confirmed using the ICP-OES (Inductively coupled plasma optical emission spectroscopy spectroscopy). The calculated average grain size for powders was in the range of 25 to 90 nm. The luminescence properties of vanadium-substituted hydroxyapatite were evaluated by recording emission spectra and excitation spectra as well as luminescence kinetics. The crucial step of this research was the evaluation of the biocompatibility of the synthesized nanomaterials. Therefore, the obtained compounds were tested toward sheep red blood cells and normal human dermal fibroblast to confirm the nontoxicity and biocompatibility of new nanosized Eu3+ ion-doped vanadate-hydroxyapatite. Moreover, the final step of the research allowed us to determine the time dependent ion release to the simulated body fluid environment. The study confirmed cytocompatibility of vanadium hydroxyapatite doped with Eu3+ ions.

scholarly journals Enhanced Defluoridation of Water Using Zirconium—Coated Pumice in Fixed-Bed Adsorption Columns

Materials ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6145
Author(s):  
Wondwosen Sime Geleta ◽  
Esayas Alemayehu ◽  
Bernd Lennartz
Keyword(s):  
Adsorption Capacity ◽  
Flow Rate ◽  
Inductively Coupled Plasma ◽  
Fixed Bed ◽  
Correlation Coefficients ◽  
Volumetric Flow Rate ◽  
Optical Emission ◽  
X Ray ◽  
Bet Analysis ◽  
Fixed Bed Adsorption

Millions of people across the globe suffer from health issues related to high fluoride levels in drinking water. The purpose of this study was to test modified pumice as an adsorbent for the purification of fluoride-containing waters. The adsorption of fluoride onto zirconium-coated pumice (Zr–Pu) adsorbent was examined in fixed-bed adsorption columns. The coating of zirconium on the surface of VPum was revealed by X-ray diffractometer (XRD), Inductively coupled plasma-optical emission spectroscopy (ICP-EOS), and X-ray fluorescence (XRF) techniques. The degree of surface modification with the enhanced porosity of Zr–Pu was evident from the recorded scanning electron microscope (SEM) micrographs. The Brunauer-Emmett-Teller (BET) analysis confirmed the enhancement of the specific surface area of VPum after modification. The Fourier transform infrared (FTIR) examinations of VPum and Zr–Pu before and after adsorption did not reveal any significant spectrum changes. The pH drift method showed that VPum and Zr–Pu have positive charges at pHPZC lower than 7.3 and 6.5, respectively. Zr–Pu yielded a higher adsorption capacity of 225 mg/kg (2.05 times the adsorption capacity of VPum: 110 mg/kg), at pH = 2 and volumetric flow rate (QO) of 1.25 mL/min. Breakthrough time increases with decreasing pH and flow rate. The experimental adsorption data was well-matched by the Thomas and Adams-Bohart models with correlation coefficients (R2) of ≥ 0.980 (Zr–Pu) and ≥ 0.897 (VPum), confirming that both models are suitable tools to design fixed-bed column systems using volcanic rock materials. Overall, coating pumice with zirconium improved the defluoridation capacity of pumice; hence, a Zr–Pu-packed fixed-bed can be applied for defluoridation of excess fluoride from groundwater. However, additional investigations on, for instance, the influences of competing ions are advisable to draw explicit conclusions.

scholarly journals Fine Characterization of Natural SiO2-Doped Catalyst Derived from Mussel Shell with Potential Photocatalytic Performance for Organic Dyes

Catalysts ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1130
Author(s):  
Zhen Wang ◽  
Liping Xia ◽  
Jinlong Chen ◽  
Lili Ji ◽  
Yarui Zhou ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Organic Dyes ◽  
Degradation Products ◽  
Diffuse Reflectance Spectrum ◽  
Optical Emission ◽  
Hydroxyl Groups ◽  
Mussel Shell ◽  
Liquid Chromatograph ◽  
Scanning Electron

In this work, a SiO2-doped natural photocatalyst derived from waste mussel shell (HAS) was prepared by acidification. The as-prepared sample was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), inductively coupled plasma-optical emission spectroscopy (ICP-OES), field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), UV-visible diffuse-reflectance spectrum (UV-vis DRS), and Differential scanning and thermogravimetric analyses (DTA/TGA). The results exhibited that HAS was mesopores nanomaterial consisting of uneven arranged rod-like structure, the dominant component of HAS was SiO2 with a large number of hydroxyl groups, and a variety of transition metals uniformly distributed in HAS. Rhodamine B (RhB) and methylene blue (MB) removal efficiencies (equal to 92.59% and 99.14%, respectively) were observed under the HAS presence when exposed to the visible light. The degradation products were analyzed using liquid Chromatograph Mass Spectrometer (LC-MS) and Total Organic Carbon (TOC), among which, MB was degraded by demethylation and deamination, and RhB was degraded by N-deethylation and conjugate structure destruction. After four successive recycles, the removal efficiency of RhB and MB are still reach 86.103% and 75.844%. This study indicated that the mussel shells might be suggested as a novel natural photocatalyst in the application of dye wastewater treatment.

scholarly journals VC-Precipitation Kinetics Studied by Small-Angle Neutron Scattering in Nano-Steels

2018 ◽  
Vol 941 ◽  
pp. 236-244 ◽  
Author(s):  
Chrysoula Ioannidou ◽  
Zaloa Arechabaleta ◽  
Arjan Rijkenberg ◽  
Robert M. Dalgliesh ◽  
A.A. van Well ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Neutron Scattering ◽  
Small Angle ◽  
Inductively Coupled Plasma ◽  
Small Angle Neutron Scattering ◽  
Volume Fraction ◽  
Optical Emission ◽  
Scattering Data ◽  
High Tech ◽  
Precipitation Kinetics

Nanosteels are used in automotive applications to accomplish resource-efficiency while providing high-tech properties. Quantitative data and further understanding on the precipitation kinetics in Nanosteels can contribute to fulfil this goal. Small-Angle Neutron Scattering measurements are performed on a Fe-C-Mn-V steel, previously heat-treated in a dilatometer at 650°C for several holding times from seconds to 10 hours. The evolution of the precipitate volume fraction, size distribution and number density is calculated by fitting the experimental Small-Angle Neutron Scattering curves. The effect of phase transformation on precipitation kinetics is also discussed. Complementary Transmission Electron Microscopy, Scanning Electron Microscopy and Inductively Coupled Plasma Optical Emission Spectroscopy measurements are performed to support the Small-Angle Neutron Scattering data analysis.

Carbon-Supported Nickel Nanoparticles from a Wood Sample of the Tree Sebertia acuminata Pierre ex. Baillon

2010 ◽  
Vol 63 (5) ◽  
pp. 830 ◽  
Author(s):  
Martin Lerch ◽  
Thorsten Ressler ◽  
Frank Krumeich ◽  
Jean-Pierre Cosson ◽  
Edouard Hnawia ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Wood Sample ◽  
Nickel Nanoparticles ◽  
Nickel Content ◽  
Optical Emission ◽  
Inert Atmosphere ◽  
X Ray ◽  
Nickel Hyperaccumulator ◽  
Crystallite Sizes

A wood sample of the nickel hyperaccumulator tree Sebertia acuminata Pierre ex. Baillon was pyrolyzed in an inert atmosphere to produce a charcoal-like material containing nanoparticulate nickel. Its overall nickel content was determined to be ~7 wt-% by wet chemical analysis (acid digestion, inductively coupled plasma optical emission spectroscopy). Depending on the conditions of pyrolysis (5 h at 800°C; or 5 h at 800°C followed by 7 h at 900°C), the average crystallite sizes were ~7 and 42 nm, respectively, as determined by X-ray powder diffraction (XRD) and electron microscopy (scanning, scanning transmission, and transmission). Furthermore, high resolution transmission electron microscopy images reveal that the Ni particles are, in some cases, encapsulated with graphitic carbon layers of varying thickness. Scanning electron microscopy results indicate for the most part, a preservation of the wood framework and a remarkably uniform distribution of the nickel nanoparticles in the vessels of the xylem. XRD and X-ray absorption fine structure analysis reveal the presence of NiO besides Ni.

scholarly journals Pd NPs supported on halloysite functionalized with Schiff base as an efficient catalyst for Sonogashira reaction

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mansoureh Daraie ◽  
Majid M. Heravi ◽  
Yalda Rangraz ◽  
Zahra Besharati
Keyword(s):  
Electron Microscopy ◽  
Schiff Base ◽  
Inductively Coupled Plasma ◽  
Aqueous Media ◽  
Optical Emission ◽  
Sonogashira Reaction ◽  
Emission Spectrometry ◽  
Efficient Catalyst ◽  
X Ray ◽  
Catalytic Support

AbstractA hybrid system was designed and synthesized through reacting modified halloysite (Hal-Cl) with Schiff base (DAB-PC) and applied as catalytic support for anchoring Pd NPs to afford Pd@Hal-DAB-PC catalyst. The resultant material was well identified by various analyses including Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction patterns (XRD), thermogravimetric analysis (TGA), field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), and inductively coupled plasma-optical emission spectrometry (ICP-OES) and revealed outstanding catalytic activity in the Sonogashira reaction in aqueous media. Also, This nanocatalyst was simply collected and recycled up to six runs with a slight drop in efficiency, indicating the durability of Pd@Hal-DAB-PC.

scholarly journals Study of gold nanoparticles’ preparation through ultrasonic spray pyrolysis and lyophilisation for possible use as markers in LFIA tests

2021 ◽  
Vol 10 (1) ◽  
pp. 1978-1992
Author(s):  
Žiga Jelen ◽  
Peter Majerič ◽  
Matej Zadravec ◽  
Ivan Anžel ◽  
Martin Rakuša ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Inductively Coupled Plasma ◽  
Ultrasonic Spray Pyrolysis ◽  
Optical Emission ◽  
Test Strip ◽  
Emission Spectrometry ◽  
Scattering Method ◽  
Dynamic Light Scattering Method ◽  
Energy Dispersion Spectrometer ◽  
Improved Stability

Abstract To monitor the progress and prevent the spread of the COVID-19 pandemic in real time and outside laboratories, it is essential to develop effective tests that can ensure rapid, selective, and reliable diagnosis of infected persons in different environments. Key in this regard is the lateral flow immunoassays (LFIAs) that can detect the presence of the SARS-CoV-2 virus quickly, with the aid of nanoparticles (NPs) and specific proteins. We report the use of gold (Au) NPs AuNPs synthesised from a gold(iii) chloride tetrahydrate precursor in a USP device and collected in a suspension composed of deionised water with polyvinylpyrrolidone as a stabiliser and cryoprotectant. In combination with freeze-drying of the AuNPs’ suspension to achieve water elimination, improved stability, and the target concentration, they exhibit the necessary properties for use as markers in LFIA rapid diagnostic tests. This was confirmed by complementary characterisation determined by using the techniques including inductively coupled plasma-optical emission spectrometry, dynamic light scattering method and zeta-potential, ultraviolet-visible spectroscopy, X-ray diffraction, scanning electron microscopy with energy dispersion spectrometer, and transmission electron microscopy, as well as with the preparation of a prototype LFIA test strip with AuNPs. Thus, such AuNPs, as well as the USP method, show promise for the development of new markers for use in LFIA.

scholarly journals CO2 Methanation over Hydrotalcite-Derived Nickel/Ruthenium and Supported Ruthenium Catalysts

Catalysts ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1008 ◽  
Author(s):  
Joana A. Martins ◽  
A. Catarina Faria ◽  
Miguel A. Soria ◽  
Carlos V. Miguel ◽  
Alírio E. Rodrigues ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Optical Emission ◽  
Space Velocity ◽  
Catalytic Performance ◽  
Ruthenium Catalysts ◽  
Emission Spectrometry ◽  
Co2 Conversion ◽  
Co2 Methanation ◽  
Inductively Coupled ◽  
Weight Hourly Space Velocity

In this work, in-house synthesized NiMgAl, Ru/NiMgAl, and Ru/SiO2 catalysts and a commercial ruthenium-containing material (Ru/Al2O3com.) were tested for CO2 methanation at 250, 300, and 350 °C (weight hourly space velocity, WHSV, of 2400 mLN,CO2·g−1·h−1). Materials were compared in terms of CO2 conversion and CH4 selectivity. Still, their performances were assessed in a short stability test (24 h) performed at 350 °C. All catalysts were characterized by temperature programmed reduction (TPR), X-ray diffraction (XRD), N2 physisorption at −196 °C, inductively coupled plasma optical emission spectrometry (ICP-OES), and H2/CO chemisorption. The catalysts with the best performance (i.e., the hydrotalcite-derived NiMgAl and Ru/NiMgAl) seem to be quite promising, even when compared with other methanation catalysts reported in the literature. Extended stability experiments (240 h of time-on-stream) were performed only over NiMgAl, which was selected based on catalytic performance and estimated price criteria. This catalyst showed some deactivation under conditions that favor CO formation (high temperature and high WHSV, i.e., 350 °C and 24,000 mLN,CO2·g−1·h−1, respectively), but at 300 °C and low WHSV, excellent activity (ca. 90% of CO2 conversion) and stability, with nearly complete selectivity towards methane, were obtained.

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