Preparation and Evaluation of Fe2O3/Ceramic Composites for Flue Gas Desulfurization

2011 ◽  
Vol 117-119 ◽  
pp. 1410-1413
Author(s):  
Xin Min ◽  
Jun Jie Bian ◽  
Shu Zhang ◽  
Chun Hu Li ◽  
Li Juan Feng
Keyword(s):  
Removal Efficiency ◽  
Flue Gas ◽  
Ferric Oxide ◽  
Sol Gel ◽  
Ceramic Composites ◽  
Ceramic Surface ◽  
Sem Images ◽  
Calcination Temperatures ◽  
Structure Morphology ◽  
Oxide Composites

Ceramic supported ferric oxide composites were synthesized by impregnation- precipitation (I) and sol-gel (II) methods using FeSO4as a precursor. We investigated the effect of the calcination temperatures on the structure, morphology, and agglomeration of supported ferric oxide. It has been found that Fe2O3was stabilized when the as-synthesized composites were calcinated at 330-360 °C under 10% (v/v) O2/N2mixture, and the calcination temperature was chosen as 350°C . The SEM images demonstrated that for the composite I, which was prepared by method (I), Fe2O3 nanoparticles were distributed on the surface and pores of the ceramic; while for the composite II, which was synthesized by method (II), Fe2O3thin layer was covered the surface of the ceramic. EDS analysis showed 7.9% (wt) ferric oxide had been supported on the composite I and up to 13.3% (wt) ferric oxide on the composite II. XPS analysis revealed that the valence of iron was +3 on both composites. Fe2O3/ceramic composites were used as the catalysts for low temperature wet Flue Gas Desulphurization (FGD), and demonstrated higher SO2removal efficiency. Because of the excellent hydrophilicity of ceramic and high dispersibility of Fe2O3 on ceramic surface, this catalyst had high SO2removal efficiency at 60°C even at pH2O3/ceramic composites, prepared by a simple, reproducible impregnation-precipitation and sol-gel method, was an inexpensive, active catalyst for S(IV) catalytic oxidation in wet FGD process in an economical feasible temperature range.

Synthesis, Characterization and Properties of PANI/(La-Nd Doped BaFe12O19) Composites

2017 ◽  
Vol 727 ◽  
pp. 327-334
Author(s):  
Yan Wang ◽  
Jun Wang ◽  
Xiao Fei Zhang ◽  
Ya Qing Liu
Keyword(s):  
Sol Gel ◽  
Network Analyzer ◽  
X Ray Diffraction ◽  
Sem Images ◽  
Structure Morphology ◽  
Xrd Patterns ◽  
Hexagonal Platelet ◽  
Peak Value ◽  
Properties Of Composites

La-Nd co-doped barium hexaferrites, Ba0.7(LamNdn)0.3Fe12O19 (D-BaM), were successfully prepared by sol-gel method. PANI / D-BaM composites were synthesized by in-situ polymerization in solution. The structure, morphology and properties of samples have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), four-probe conductivity tester and vector network analyzer. The XRD patterns showed that the crystal structure of all the samples exist as M-type phases. The SEM images revealed that the particles presented a hexagonal platelet-like morphology. The magnetic properties could be improved by substitutions of La and Nd ions. The saturation magnetization (Ms) and coercive force (Hc) increased with the change of La / Nd ratio to the maximum at La / Nd = 3:1. The doped particles have also been embedded in conductive PANI to prepare electromagnetic materials, and the conductivity kept on the order of 10-2. The microwave absorbing properties of composites at 30 MHz-6 GHz improved obviously, the peak value of reflection loss could reach-7.5 dB.

scholarly journals Yb-Doped BaCeO3 and Its Composite Electrolyte for Intermediate-Temperature Solid Oxide Fuel Cells

Materials ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 739
Author(s):  
Xueyue Jiang ◽  
Fufang Wu ◽  
Hongtao Wang
Keyword(s):  
Solid Oxide Fuel Cells ◽  
Raw Materials ◽  
Sol Gel ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
Barium Acetate ◽  
Sem Images ◽  
Composite Electrolyte ◽  
Fuel Cell Performance ◽  
Structure Morphology

BaCe0.9Yb0.1O3−α was prepared via the sol-gel method using zirconium nitrate, ytterbium trioxide, cerium nitrate and barium acetate as raw materials. Subsequently, it reacted with the binary NaCl~KCl salt to obtain BaCe0.9Yb0.1O3−α-NaCl~KCl composite electrolyte. The structure, morphology, conductivity and fuel cell performance of the obtained samples were investigated. Scanning electron microscope (SEM) images showed that BaCe0.9Yb0.1O3−α and NaCl~KCl combined with each other to form a homogeneous 3-D reticulated structure. The highest power density and conductivity of BaCe0.9Yb0.1O3−α-NaCl~KCl was 393 mW·cm−2 and 3.0 × 10−1 S·cm−1 at 700 °C, respectively.

scholarly journals Catalytic Oxidation of Toluene Over LaNixB1-xO3 (B=Co, Cu) Perovskite Catalysts

2021 ◽  
Author(s):  
Songya Qi ◽  
Wanqi Zhang ◽  
Xiang Li ◽  
Qing Wang ◽  
Zerui Zhu ◽  
...  
Keyword(s):  
Sol Gel ◽  
Molar Ratio ◽  
Toluene Degradation ◽  
Co Doping ◽  
Calcination Temperatures ◽  
Structure Morphology ◽  
Volatile Organic ◽  
Volatile Organic Pollutants ◽  
Perovskite Catalysts ◽  
Short Time

Abstract A series of LaNixB1-xO3 (B=Co, Cu) perovskite catalysts were prepared by sol-gel method and employed in toluene degradation. The catalysts were characterized by XRD, UV-Vis, SEM and XPS to investigate crystal structure, morphology and composition of the catalyst. The effect of different calcination temperatures and time on the performance of perovskite catalysts for toluene degradation were investigated. And the CO2 selectivity was also carried out on as-prepared catalysts. The results showed that a small amount of Co-doping in B site of LaNiO3 could significantly improve its toluene degradation, while the substitution of Ni with Cu could not effectively enhance its activity. When the Ni/Co molar ratio in LaNixCo1-xO3 perovskite was 3:1, LaNi0.75Co0.25O3 catalyst exhibited the best activity, and it showed relatively short time and low temperature for toluene conversion of 100%. Therefore, LaNi0.75Co0.25O3 catalyst has a broad prospect in the degradation of volatile organic pollutants.

scholarly journals Sol-Gel Synthesis, Structure, Morphology and Magnetic Properties of Ni0.6Mn0.4Fe2O4 Nanoparticles Embedded in SiO2 Matrix

Nanomaterials ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3455
Author(s):  
Thomas Dippong ◽  
Erika Andrea Levei ◽  
Iosif Grigore Deac ◽  
Ioan Petean ◽  
Gheorghe Borodi ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
Secondary Phase ◽  
Ferromagnetic Behavior ◽  
Sio2 Matrix ◽  
Calcination Temperatures ◽  
Structure Morphology ◽  
A Minor ◽  
Sol Gel Synthesis

The structure, morphology and magnetic properties of (Ni0.6Mn0.4Fe2O4)α(SiO2)100−α (α = 0–100%) nanocomposites (NCs) produced by sol-gel synthesis were investigated using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), atomic force microscopy (AFM) and vibrating sample magnetometry (VSM). At low calcination temperatures (300 °C), poorly crystallized Ni0.6Mn0.4Fe2O4, while at high calcination temperatures, well-crystallized Ni0.6Mn0.4Fe2O4 was obtained along with α-Fe2O3, quartz, cristobalite or iron silicate secondary phase, depending on the Ni0.6Mn0.4Fe2O4 content in the NCs. The average crystallite size increases from 2.6 to 74.5 nm with the increase of calcination temperature and ferrite content embedded in the SiO2 matrix. The saturation magnetization (Ms) enhances from 2.5 to 80.5 emu/g, the remanent magnetization (MR) from 0.68 to 12.6 emu/g and the coercive field (HC) from 126 to 260 Oe with increasing of Ni0.6Mn0.4Fe2O4 content in the NCs. The SiO2 matrix has a diamagnetic behavior with a minor ferromagnetic fraction, Ni0.6Mn0.4Fe2O4 embedded in SiO2 matrix displays superparamagnetic behavior, while unembedded Ni0.6Mn0.4Fe2O4 has a high-quality ferromagnetic behavior.

The Effects of Calcination Temperatures in the Synthesis of Nanocrystalline Magnesium Oxide via Sol-Gel Technique

2017 ◽  
Vol 865 ◽  
pp. 36-42
Author(s):  
Hanis Mohd Yusoff ◽  
Faridatul Akmar Rafit ◽  
Fatin Izwani Mohamad ◽  
Norhafiefa Hassan ◽  
Adibah Izzati Daud
Keyword(s):  
Magnesium Oxide ◽  
Sol Gel ◽  
Combustion Method ◽  
Metal Nitrate ◽  
Complexing Agent ◽  
Sem Images ◽  
Calcination Temperatures ◽  
Xrd Patterns ◽  
Adsorption Desorption ◽  
Nanocrystalline Magnesium Oxide

This study highlights on a convenient and optimised method for the preparation of nanocrystalline magnesium oxide (MgO) catalyst via sol-gel combustion method. Nanocrystalline MgO was prepared by using polyvinyl alcohol (PVA) as a complexing agent and metal nitrate (Mg (NO 3 )2.6H2O) as a precursor. The obtained MgO powder was calcined at 200 °C, 400 °C, 600 °C and 800 °C. All the MgO calcined samples including commercial MgO were characterised using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-Ray diffraction (XRD) and N2 adsorption-desorption Brunauer–Emmett–Teller (BET). From FTIR analysis, the appearance of a peak at 3700 cm-1 represent the O-H stretching bonded with Mg and the broad absorption peak at 3421 cm-1 indicates O-H stretching band which is due to the absorption of moisture from the surrounding. (BET) results indicate the MgO sample that has been calcined at 400 °C shows the largest surface area. SEM images show there is porosity in all MgO powder. While XRD patterns revealed that higher temperature of calcination gives higher crystallinity of the MgO samples.

Blue Emitting BaAl2O4:Ce3+ Nanophosphors with High Color Purity and Brightness for White LEDs

2019 ◽  
Vol 25 (6) ◽  
pp. 1466-1470 ◽  
Author(s):  
Rituparna Chatterjee ◽  
Subhajit Saha ◽  
Karamjyoti Panigrahi ◽  
Uttam Kumar Ghorai ◽  
Gopes Chandra Das ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Field Emission ◽  
Sol Gel ◽  
Blue Emission ◽  
Diffraction Field ◽  
White Leds ◽  
Display Devices ◽  
Transmission Electron ◽  
Structure Morphology ◽  
The Impact

AbstractIn this work, strongly blue emitting Ce3+-activated BaAl2O4 nanophosphors were successfully synthesized by a sol–gel technique. The crystal structure, morphology, and microstructure of the nanophosphors have been studied by X-ray powder diffraction, field emission scanning electron microscopy, and high-resolution transmission electron microscopy. The photoluminescence spectra show the impact of concentration variation of Ce3+ on the photoluminescence emission of the phosphor. These nanophosphors display intense blue emission peaking at 422 nm generated by the Ce3+ 5d → 4f transition under 350 nm excitation. Our results reveal that this nanophosphor has the capability to take part in the emergent domain of solid-state lighting and field-emission display devices.

scholarly journals Synthesis, Structural, Morphological and Thermal Characterization of Five Different Silica-Polyethylene Glycol-Chlorogenic Acid Hybrid Materials

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1586
Author(s):  
Michelina Catauro ◽  
Pavel Šiler ◽  
Jiří Másilko ◽  
Roberta Risoluti ◽  
Stefano Vecchio Ciprioti
Keyword(s):  
Polyethylene Glycol ◽  
Chlorogenic Acid ◽  
Hybrid Materials ◽  
Sol Gel ◽  
Antibacterial Properties ◽  
Silica Matrix ◽  
Sem Images ◽  
Fixed Amount ◽  
Organic Components ◽  
Free Material

The present study investigated the structure, morphology, thermal behavior, and bacterial growth analysis of novel three-component hybrid materials synthesized by the sol-gel method. The inorganic silica matrix was weakly bonded to the network of two organic components: a well-known polymer such as polyethylene glycol (PEG, average molar mass of about 4000 g/mol), and an antioxidant constituted by chlorogenic acid (CGA). In particular, a first series was made by a 50 wt% PEG-based (CGA-free) silica hybrid along with two 50 wt% PEG-based hybrids containing 10 and 20 wt% of CGA (denoted as SP50, SP50C10 and SP50C20, respectively). A second series contained a fixed amount of CGA (20 wt%) in silica-based hybrids: one was the PEG-free material (SC20) and the other two contained 12 and 50 wt% of PEG, respectively (SP12C20 and SP50C20, respectively), being the latter already included in the first series. The X-ray diffraction (XRD) patterns and scanning electron microscope (SEM) images of freshly prepared materials confirmed that all the materials were amorphous and homogeneous regardless of the content of PEG or CGA. The thermogravimetric (TG) analysis revealed a higher water content was adsorbed into the two component hybrids (SP50 and SC20) because of the availability of a larger number of H-bonds to be formed with water with respect to those of silica/PEG/CGA (SPC), where silica matrix was involved in these bonds with both organic components. Conversely, the PEG-rich materials (SP50C10 and SP50C20, both with 50 wt% of the polymer) retained a lower content of water. Decomposition of PEG and CGA occurred in almost the same temperature interval regardless of the content of each organic component. The antibacterial properties of the SiO2/PEG/CGA hybrid materials were studied in pellets using either Escherichia coli and Enterococcus faecalis, respectively. Excellent antibacterial activity was found against both bacteria regardless of the amount of polymer in the hybrids.

scholarly journals Nanostructured LiFe5O8 by a Biogenic Method for Applications from Electronics to Medicine

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 193
Author(s):  
Silvia Soreto Teixeira ◽  
Manuel P. F. Graça ◽  
José Lucas ◽  
Manuel Almeida Valente ◽  
Paula I. P. Soares ◽  
...  
Keyword(s):  
Spinel Ferrite ◽  
Sol Gel ◽  
Reaction Medium ◽  
Magnetic Hyperthermia ◽  
Magnetic Characteristics ◽  
Secondary Phases ◽  
Heat Treated ◽  
Structure Morphology ◽  
Sol Gel Process ◽  
Crystallite Sizes

The physical properties of the cubic and ferrimagnetic spinel ferrite LiFe5O8 has made it an attractive material for electronic and medical applications. In this work, LiFe5O8 nanosized crystallites were synthesized by a novel and eco-friendly sol-gel process, by using powder coconut water as a mediated reaction medium. The dried powders were heat-treated (HT) at temperatures between 400 and 1000 °C, and their structure, morphology, electrical and magnetic characteristics, cytotoxicity, and magnetic hyperthermia assays were performed. The heat treatment of the LiFe5O8 powder tunes the crystallite sizes between 50 nm and 200 nm. When increasing the temperature of the HT, secondary phases start to form. The dielectric analysis revealed, at 300 K and 10 kHz, an increase of ε′ (≈10 up to ≈14) with a tanδ almost constant (≈0.3) with the increase of the HT temperature. The cytotoxicity results reveal, for concentrations below 2.5 mg/mL, that all samples have a non-cytotoxicity property. The sample heat-treated at 1000 °C, which revealed hysteresis and magnetic saturation of 73 emu g−1 at 300 K, showed a heating profile adequate for magnetic hyperthermia applications, showing the potential for biomedical applications.

scholarly journals Tough metal-ceramic composites with multifunctional nacre-like architecture

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Erik Poloni ◽  
Florian Bouville ◽  
Christopher H. Dreimol ◽  
Tobias P. Niebel ◽  
Thomas Weber ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Sol Gel ◽  
Ceramic Composites ◽  
High Fracture Toughness ◽  
Processing Route ◽  
High Fracture ◽  
Metal Ceramic ◽  
Attractive Option ◽  
Brick And Mortar ◽  
Robotic Applications

AbstractThe brick-and-mortar architecture of biological nacre has inspired the development of synthetic composites with enhanced fracture toughness and multiple functionalities. While the use of metals as the “mortar” phase is an attractive option to maximize fracture toughness of bulk composites, non-mechanical functionalities potentially enabled by the presence of a metal in the structure remain relatively limited and unexplored. Using iron as the mortar phase, we develop and investigate nacre-like composites with high fracture toughness and stiffness combined with unique magnetic, electrical and thermal functionalities. Such metal-ceramic composites are prepared through the sol–gel deposition of iron-based coatings on alumina platelets and the magnetically-driven assembly of the pre-coated platelets into nacre-like architectures, followed by pressure-assisted densification at 1450 °C. With the help of state-of-the-art characterization techniques, we show that this processing route leads to lightweight inorganic structures that display outstanding fracture resistance, show noticeable magnetization and are amenable to fast induction heating. Materials with this set of properties might find use in transport, aerospace and robotic applications that require weight minimization combined with magnetic, electrical or thermal functionalities.

Multi-Phasic Ceramic Composites made by Sol-Gel Technique

1984 ◽  
Vol 32 ◽  
Author(s):  
Rustum Roy ◽  
S. Komarneni ◽  
D.M. Roy
Keyword(s):  
Single Phase ◽  
Crystal Size ◽  
Sol Gel ◽  
Ceramic Composites ◽  
Silver Halides ◽  
Metal Atoms ◽  
Metallic Salts ◽  
Second Phases ◽  
Gel Technique ◽  
Work Done

ABSTRACTInstead of aiming to prepare homogeneous gels and xerogels, this paper reports on work done to prepare deliberately diphasic materials. This has been achieved by three different paths: (1) mixing 2 sols; (2) mixing 1 sol with 1 solution; and (3) post formation diffusion of either one or two solutions.By the last named process we have made SiO2, mullite and alumina based composites, with silver halides, BaSO4, CdS, etc., as the dispersed phase. The crystal size can be confined to the initial pores by rapid diffusion giving rise to extremely fine second phases in the submicron range. Subsequent reduction of appropriate metallic salts can be used to give finely dispersed metals (e.g. Cu, Ni) in essentially any xerogel matrix. The open porosity makes these metal atoms very accessible.By the first two processes we have made both single phase and di-phasic gels of the same composition (prototype: mullite) and shown that though they cannot be distinguished by XRD, SEM, and TEM, by DTA and thermal processing, they are radically different. Such di-phasic gels store more metastable energy than any other solids.

Sign in / Sign up

Export Citation Format

Share Document