Preparation of Cu-Al/SiO2 Porous Material and Its Effect on NO Decomposition in a Cement Kiln

Nitrogen oxide (NOx) emissions have attracted much attention for increasing concern on the quality of the atmospheric environment. In view of NO decomposition in the cement production process, the preparation of Cu-Al/SiO2 porous material and its effect on NO decomposition were studied, and the denitrification mechanism was proposed in this paper. The NO decomposition performance of the Cu-Al/SiO2 porous material was tested via the experimental setup and infrared spectrometer and micro gas chromatography (GC). The result shows that the Cu-Al/SiO2 porous material with the template of cetyltrimethylammonium bromide (CTAB) had a better NO decomposition rate than materials with other templates when the temperature was above 500 °C, and NO decomposition rate could approach 100% at high temperatures above 750 °C. Structure analysis indicates that the prepared Cu-Al/SiO2 material structure was a mesoporous structure. The X-Ray Diffraction (XRD) and Ultraviolet–visible spectrophotometry (UV–Vis) results of the denitrification product show that the Cu-Al/SiO2 material mainly decomposed to Cu2O and Si2O, and the CuO decomposed to Cu2O and O2 at high temperature. The Cu(I)O was considered as the active phase. The redox process between Cu(II)O and Cu(I)O was thought to be the denitrification mechanism of the Cu-Al/SiO2 porous material.

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Influence of Catalysts with Different Templates on Direct Decomposition of NO in Cement Kiln Exhaust

Materials Science Forum ◽

10.4028/www.scientific.net/msf.913.948 ◽

2018 ◽

Vol 913 ◽

pp. 948-953

Author(s):

Yan Ling Gan ◽

Su Ping Cui ◽

Hong Xia Guo ◽

Xiao Yu Ma ◽

Ya Li Wang

Keyword(s):

Surface Area ◽

Decomposition Rate ◽

Nitrogen Adsorption ◽

Catalytic Performance ◽

Direct Decomposition ◽

No Decomposition ◽

Bet Surface Area ◽

Cement Kiln ◽

Porous Catalyst ◽

Decomposition Of No

The influence of catalysts with different templates on direct decomposition of NO in cement kiln exhaust was studied in this paper. The NO direct decomposition rate of porous catalyst materials with different templates was determined by infrared spectrometer. And pore structure and the microstructure of the catalysts were characterized by BET surface area, nitrogen adsorption-desorption. The results show that the catalytic performance of porous catalyst without any template is better than catalysts with other templates at low temperature. When the temperature reached 550 °C, NO decomposition rate of porous catalyst with CTAB could reach to more than 80%. And meanwhile, the catalysts with organic template reagent have higher BET surface area than those with inorganic template agent. With the increasing of the reaction time, the NO decomposition rate decreases. After reaction for 3 hours, the decomposition rate decreases from 80% to 40%.

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Effect of Silica-Alumina Ratio of Catalysts on NO Decomposition Rate in Cement Kiln Exhaust

Materials Science Forum ◽

10.4028/www.scientific.net/msf.993.1450 ◽

2020 ◽

Vol 993 ◽

pp. 1450-1455

Author(s):

Yan Ling Gan ◽

Su Ping Cui ◽

Xiao Yu Ma ◽

Ya Li Wang

Keyword(s):

Surface Area ◽

Decomposition Rate ◽

Catalytic Decomposition ◽

Nitrogen Adsorption ◽

No Decomposition ◽

Bet Surface Area ◽

Cement Kiln ◽

Average Pore ◽

Silica Alumina ◽

Silica Alumina Ratio

In order to deal with the pollution of NO in cement kiln exhaust, the study of NO catalytic decomposition catalyst obtained much more attention. The effect of silica-alumina ratio on NO decomposition rate in cement kiln without other reductant was studied. The NO decomposition rate of catalysts with different silica-alumina ratio was determined by infrared spectrometer. And pore structures and the microstructure of the catalyst were characterized separately by BET surface area, nitrogen adsorption-desorption and XRD. The results show that silica-alumina ratio of catalyst was preferred to be 50 with the best NO decomposition rate when the temperature was below 300 °C. The catalyst with silica-alumina ratio of 60 has the higher catalytic activity when the temperature was higher than 300 °C, and the decomposition rate achieved 70% at 600 °C. XRD results shows the crystallinity of catalysts increased as the silica-alumina ratio increased. BET surface area and the cumulative pore volume of catalysts gradually increased, and the average pore diameter gradually reduced with the increase of silica-alumina ratio.

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Investigation of Solvatomorphism and Its Photophysical Implications for Archetypal Trinuclear Au3(1-Methylimidazolate)3

Molecules ◽

10.3390/molecules26154404 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4404

Author(s):

Shengyang Guan ◽

David C. Mayer ◽

Christian Jandl ◽

Sebastian J. Weishäupl ◽

Angela Casini ◽

...

Keyword(s):

Crystal Structure ◽

Solid State ◽

Density Functional ◽

Bulk Material ◽

Variable Temperature ◽

Active Phase ◽

Solvent Free ◽

X Ray Diffraction ◽

X Ray ◽

Aurophilic Interactions

A new solvatomorph of [Au3(1-Methylimidazolate)3] (Au3(MeIm)3)—the simplest congener of imidazolate-based Au(I) cyclic trinuclear complexes (CTCs)—has been identified and structurally characterized. Single-crystal X-ray diffraction revealed a dichloromethane solvate exhibiting remarkably short intermolecular Au⋯Au distances (3.2190(7) Å). This goes along with a dimer formation in the solid state, which is not observed in a previously reported solvent-free crystal structure. Hirshfeld analysis, in combination with density functional theory (DFT) calculations, indicates that the dimerization is generally driven by attractive aurophilic interactions, which are commonly associated with the luminescence properties of CTCs. Since Au3(MeIm)3 has previously been reported to be emissive in the solid-state, we conducted a thorough photophysical study combined with phase analysis by means of powder X-ray diffraction (PXRD), to correctly attribute the photophysically active phase of the bulk material. Interestingly, all investigated powder samples accessed via different preparation methods can be assigned to the pristine solvent-free crystal structure, showing no aurophilic interactions. Finally, the observed strong thermochromism of the solid-state material was investigated by means of variable-temperature PXRD, ruling out a significant phase transition being responsible for the drastic change of the emission properties (hypsochromic shift from 710 nm to 510 nm) when lowering the temperature down to 77 K.

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Controlled Synthesis of Different Morphologies of SrWO4 Crystals via a Surfactant-Assisted Hydrothermal Precipitation Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.785-786.449 ◽

2013 ◽

Vol 785-786 ◽

pp. 449-454

Author(s):

Yan Zhao ◽

Chun Yan Wu ◽

Dan Qin ◽

Xin Lai ◽

Si Wu ◽

...

Keyword(s):

Ph Value ◽

Precipitation Method ◽

Molar Ratio ◽

X Ray Diffraction ◽

X Ray ◽

Experimental Parameters ◽

Infrared Spectrometer ◽

Luminescent Spectra ◽

Hydrothermal Precipitation ◽

Surfactant Assisted

SrWO4 octahedrons, flowers, bundles, ellipsoids and dendrites had been successfully synthesized via surfactant-assisted method. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), photo-luminescent spectra techniques (PL) and fourier transrform infrared spectrometer (FTIR). By through various comparison experiments, it can be found that some related experimental parameters including the reagent concentration, [Sr2+]/[WO42-] molar ratio (R), aging temperature and the pH value had great influences on morphology of the products.

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One-Step Hydrothermal Synthesis of Bi2S3-TiO2-RGO Composites with Enhanced Visible Light Photocatalytic Activities

NANO ◽

10.1142/s1793292018500510 ◽

2018 ◽

Vol 13 (05) ◽

pp. 1850051 ◽

Cited By ~ 4

Author(s):

Yanan Li ◽

Zhongmin Liu ◽

Yaru Li ◽

Yongchuan Wu ◽

Jitao Chen ◽

...

Keyword(s):

Visible Light ◽

Photocatalytic Degradation ◽

Photogenerated Electron ◽

X Ray Diffraction ◽

Electron Hole ◽

Photocatalytic Ability ◽

Transmission Electron ◽

Light Region ◽

Infrared Spectrometer ◽

One Step

The Bi2S3-TiO2-RGO composites were synthesized by a facile one-step hydrothermal method and applied for the photocatalytic degradation of Rhodamine B (Rh B) under the visible light. The Bi2S3-TiO2-RGO composites were characterized by transmission electron microscopy, X-ray diffraction, Raman and Fourier transform infrared spectrometer. The results indicated that the Bi2S3-TiO2-RGO composites were successfully prepared, and Ti-O-C and S-C bonds were existing among Bi2S3, TiO2 as well as RGO. Furthermore, the photocatalytic ability of Bi2S3-TiO2-RGO composites was excellent under visible light due to its responding to the whole visible light region, low recombination rate of photogenerated electron–hole pairs and relatively negative conduction band. Rh B photocatalytic degradation rate was 99.5% after 50[Formula: see text]min and still could reach 98.4% after five cycles. Finally, a formation mechanism as well as a photocatalytic mechanism of Bi2S3-TiO2-RGO composites were proposed based on the experimental results.

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Preparation and Photocatalytic Properties of Rod-Shaped TiO2 Based on Salix Fiber

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.609-610.250 ◽

2014 ◽

Vol 609-610 ◽

pp. 250-254

Author(s):

Ya Bin Li ◽

Jin Tian Huang ◽

Yan Fei Pan

Keyword(s):

Photocatalytic Performance ◽

Sol Gel ◽

Average Diameter ◽

X Ray Diffraction ◽

Nanocomposite Structure ◽

X Ray ◽

Infrared Spectrometer ◽

Ft Ir ◽

Degradation Of Methyl Orange ◽

Scanning Electron

In the paper, the TiO2nanomaterials adopted the microcrystalline cellulose as the template by the template method and sol-gel method was prepared. Through the infrared spectrometer (FT-IR), scanning electron microscope (SEM), X-ray diffraction (XRD), the surface morphology, composition and the type of the samples were characterized respectively. The influence of the macro morphology of TiO2photocatalytic performance to use the reaction of decolorization and degradation of methyl orange as model was analyzed. The results showed that TiO2which was produced by the template of sallix fiber was Rod-shaped and the average diameter size of nanocomposite structure was 20.592 nm, which can provide a new method of producing other morphology of TiO2.

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Influence of B2O3 doping on synthesis of MgTiO3 ceramics from recycled magnesia-hercynite materials

Materials Research Express ◽

10.1088/2053-1591/ac3fde ◽

2021 ◽

Vol 8 (12) ◽

pp. 125901

Author(s):

Xiaodong Jia ◽

Shuo Mao ◽

Lin Tian ◽

Shujiang Chen ◽

Guohua Li ◽

...

Keyword(s):

Dielectric Properties ◽

Raw Materials ◽

Microwave Dielectric Properties ◽

Synthesis Rate ◽

Cement Kiln ◽

X Ray Diffraction ◽

Optimum Amount ◽

X Ray ◽

Microwave Dielectric ◽

Microstructural Studies

Abstract Herein, magnesium metatitanate (MgTiO3) ceramics were synthesised using recycled magnesia-hercynite (MH) bricks as the raw materials to achieve solid waste reusing of cement kiln refractories. The recycled MH materials were mixed with anatase TiO2 to investigate the effect of addition of doped B2O3 during the synthesis of MgTiO3 ceramics at 1400 °C. Phase compositions and microstructural studies were performed using x-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. In addition, energy-dispersive spectroscopy (EDS) was conducted and the dielectric properties of the samples were studied. Results show that the addition of B2O3 can promote sintering, improve shrinkage, promote densification, stabilise MgTiO3 lattice, and inhibit the formation of MgTiO3. In addition, the presence of appropriate amount of B2O3 can accelerate the material diffusion and result in grain growth through the formation of intercrystalline liquid phase. Results also suggest that an increase in dielectric constant results in a decrease in dielectric loss. It was concluded that 2 wt% was the optimum amount of B2O3 required to obtain the most favourable synthesis rate of MgTiO3 (98.2%). The samples exhibited a maximum density of 3.69 g·cm−3 and excellent microwave dielectric properties at ε r = 18.28 and tanδ = 0.086.

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Corrosion Performance of TRIP Steels under Atmospheric Environment

Materials Science Forum ◽

10.4028/www.scientific.net/msf.960.3 ◽

2019 ◽

Vol 960 ◽

pp. 3-8

Author(s):

Hao Xu Wang ◽

Yi Qin Cai ◽

Zhuang Li ◽

Qi Zhou

Keyword(s):

Trip Steel ◽

Atmospheric Corrosion ◽

Alloying Elements ◽

Atmospheric Environment ◽

Protective Mechanism ◽

Corrosion Performance ◽

X Ray Diffraction ◽

X Ray ◽

Trip Steels ◽

Surface Morphologies

Atmospheric corrosion test of TRIP steels was conducted in laboratory. The surface morphologies of the specimens were analyzed by scanning electron microscope (SEM), X-ray diffraction (XRD) and electro-probe microanalysis (EPMA). Corrosion performance of TRIP steels under atmospheric environment was investigated by discussing the protective mechanism. The corrosion rates of steel A are significantly greater than steel B in atmospheric environment tests. The enhancement of corrosion performance of TRIP steel is attributed to the additions of alloying elements, such as P, Cr, Cu, and Ni etc.. The alloying elements increase the compactness and densification of rust layers. Electrochemical characteristic of TRIP steel is improved by means of the enhancement of the thermodynamic stability.

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