Synergetic Utilization of Microwave - Assisted Fly Ash and Carbide Slag for Simultaneous Desulfurization and Denitrification: High Efficiency, Low Cost and Catalytic Mechanism

Abstract The developing high-efficiency urea fuel cells have an irreplaceable role in solving the increasingly severe environmental crisis and energy shortages. The sluggish six-electron dynamic anodic oxidation reaction is the bottleneck of the rapid progress of urea fuel-cell technology. To tackle this challenge, we select the NiCr bimetallic system due to the unique synergic effect between the Ni and the Cr. Moreover, better conductivity is assured using carbon nanotubes (CNTs) as the support. Most importantly, we use a simple hydrothermal method in catalyst preparation for easy scale-up at a low cost. The results show that the hybrid catalysts of NiCrx-oxide-CNTs with different Ni/Cr ratios show much better catalytic performance in terms of active surface area and current density as compared to that of Ni-hydro-CNTs. The optimized NiCr2-oxide-CNTs catalyst exhibits not only the largest electrochemically active surface area (ESA, 50.7 m2 g−1) and the highest urea electrocatalytic current density (115.6 mA cm−2), but also outstanding long-term stability. The prominent performance of the NiCr2-oxide-CNTs catalyst is due to the combined effect of the improved charge transfer between Ni and Cr species, the large ESA, along with an elegant balance between the oxygen-defect sites and hydrophilicity. Moreover, we have proposed a synergistically enhanced urea catalytic mechanism.

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Flocculation of Harmful Algal Blooms by Modified Fly Ash

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.347-353.2090 ◽

2011 ◽

Vol 347-353 ◽

pp. 2090-2093

Author(s):

Chun Guang Miao ◽

Xiang Qin Wang ◽

Hong Zhang

Keyword(s):

Fly Ash ◽

Hydrochloric Acid ◽

Network Structure ◽

Harmful Algal Blooms ◽

Algal Blooms ◽

High Efficiency ◽

Low Cost ◽

Experimental Results ◽

Modified Fly Ash

The flocculants of fly ash(FA) and modified fly ash (mFA)were investigated in this study to evaluate their flocculation efficiencies in freshwater containing harmful algal blooms(HABs). The experimental results show that the efficiency of flocculation can be prominent improved by mFA.It was found that the fly ash modified by hydrochloric acid could form network structure bundle, algal cells were wrapped up through netting and bridging effect. So the method that removal of HABs with modified fly ash is low cost with high efficiency

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The emerging applications of metal phosphides in carbon dioxide reduction reaction

Functional Materials Letters ◽

10.1142/s1793604721300176 ◽

2021 ◽

Author(s):

Sihao Wang ◽

Gaofu Li ◽

Lei Chen ◽

Zhi Li ◽

Zhuoyan Wu ◽

...

Keyword(s):

Carbon Dioxide ◽

Electrical Conductivity ◽

High Efficiency ◽

Catalytic Mechanism ◽

Low Cost ◽

Carbon Dioxide Reduction ◽

Reduction Reaction ◽

Future Research ◽

Practical Applications ◽

Metal Phosphides

The development of low-cost and high-efficiency catalysts is very important to promote carbon dioxide reduction reaction (CO2RR). Metal phosphides (MPs) are promising catalysts for CO2 reduction because of their excellent electrical conductivity, good stability, high activity and selectivity. In this review, we summarize the latest progress of MPs in CO2RR from chemocatalysis, electrocatalysis and photocatalysis, and discuss in detail their advantages and catalytic mechanism. In the end, we provide some potential challenges and inspiring outlooks to serve as guidance for future research and practical applications of MPs in catalytic CO2 reduction.

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Synthesis and characterization of metal–organic frameworks fabricated by microwave-assisted ball milling for adsorptive removal of Congo red from aqueous solutions

RSC Advances ◽

10.1039/c7ra09243a ◽

2017 ◽

Vol 7 (73) ◽

pp. 46520-46528 ◽

Cited By ~ 27

Author(s):

Fu-hua Wei ◽

Ding Chen ◽

Zhao Liang ◽

Shuai-qi Zhao ◽

Yun Luo

Keyword(s):

Ball Milling ◽

High Efficiency ◽

Low Cost ◽

Metal Organic Frameworks ◽

Metal Salts ◽

Synthesis And Characterization ◽

Adsorptive Removal ◽

Microwave Assisted ◽

Metal Organic

In this study, four metal–organic frameworks (MOFs) were prepared using a simple, low-cost, and high-efficiency technique utilizing simple carboxylic acids and metal salts by microwave-assisted ball milling.

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Application of fly ash/granulated blast-furnace slag cementing material for immobilization of Pb2+

MATEC Web of Conferences ◽

10.1051/matecconf/201817501020 ◽

2018 ◽

Vol 175 ◽

pp. 01020 ◽

Cited By ~ 1

Author(s):

Li Chao ◽

Zhao Feng-qing

Keyword(s):

Blast Furnace ◽

Fly Ash ◽

Blast Furnace Slag ◽

Low Cost ◽

Hydration Products ◽

Experimental Conditions ◽

Granulated Blast Furnace Slag ◽

Carbide Slag ◽

Cementing Material ◽

Furnace Slag

Based on activation and synergistic effect among various materials, a low-cost cementing material. FGC binder, was prepared by using fly ash. granulated blast-furnace slag (BFS). carbide slag and compound activator. The results showed that the immobilization efficiency of FGC binder for Pb2+: is higher than that of OPC cement. The hydration products and mechanism of immobilization were analyzed by using XRD. The major products of FGC binder are C-S-H, C-A-H. ettringite and zeolite-like materials. Under the experimental conditions, the Pb2+ curing efficiency of FGC binder is 1.04 ~ 1.24 times that of ordinary Portland cement.

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Interlayer-Confined Cu(II) Complex as an Efficient and Long-Lasting Catalyst for Oxidation of H2S on Montmorillonite

Minerals ◽

10.3390/min10060510 ◽

2020 ◽

Vol 10 (6) ◽

pp. 510

Author(s):

Elena Castellini ◽

Fabrizio Bernini ◽

Lorenzo Sebastianelli ◽

Claro Ignacio Sainz-Díaz ◽

Aida Serrano ◽

...

Keyword(s):

High Efficiency ◽

Catalytic Mechanism ◽

Atmospheric Oxygen ◽

Low Cost ◽

H2s Removal ◽

X Ray ◽

S 100 ◽

Long Time ◽

Phenanthroline Complex ◽

X Ray Absorption

Removal of highly toxic H2S for pollution control and operational safety is a pressing need. For this purpose, a montmorillonite intercalated with Cu(II)-phenanthroline complex [Cu[(Phen)(H2O)2]2+ (Mt-CuPhen) was prepared to capture gaseous H2S under mild conditions. This hybrid material was simple to obtain and demonstrated an outstanding ability to entrap H2S at room temperature, retaining high efficiency for a very long time (up to 36.8 g of S/100 g Mt-CuPhen after 3 months of exposure). Sorbent and H2S uptake were investigated by elemental analysis, X-ray powder diffraction measurements, diffuse reflectance (DR) UV–Vis and infrared spectroscopy, thermal analysis and evolved gas mass spectrometry, scanning electron microscopy equipped with energy-dispersive X-ray spectrometer, and X-ray absorption spectroscopy. The H2S capture was studied over time and a mechanism of action was proposed. The entrapping involves a catalytic mechanism in which [Cu[(Phen)(H2O)2]2+ acts as catalyst for H2S oxidation to S0 by atmospheric oxygen. The low cost and the long-lasting performance for H2S removal render Mt-CuPhen an extremely appealing trap for H2S removal and a promising material for many technological applications.

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High Efficiency of the Removal Process of Pb(II) and Cu(II) Ions with the Use of Fly Ash from Incineration of Sunflower and Wood Waste Using the CFBC Technology

Energies ◽

10.3390/en14061771 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1771

Author(s):

Tomasz Kalak ◽

Ryszard Cierpiszewski ◽

Małgorzata Ulewicz

Keyword(s):

Fly Ash ◽

High Efficiency ◽

Circulating Fluidized Bed ◽

Low Cost ◽

Freundlich Isotherm ◽

Isotherm Models ◽

Fluidized Bed Combustion ◽

Effective Removal ◽

Adsorption Processes ◽

Climate Neutrality

In these research studies, fly ash (SW-FA) resulting from the incineration of sunflower (20%) and wood (80%) waste employing the circulating fluidized bed combustion (CFBC) technology was used to analyze the possibility of removing Pb(II) and Cu(II) ions in adsorption processes. Currently, great emphasis is placed on circular economy, zero waste or climate neutrality strategies. The use of low-cost SW-FA waste seems to fit well with pro-ecological, economic and energy-saving trends. Hence, this material was characterized by various techniques, such as granulation analysis, bulk density, SEM-EDX, XRD and XRF analysis, BET, BJH, thermogravimetry, zeta potential, SEM morphology and FT-IR spectrometry. As a result of the conducted research, the factors influencing the effectiveness of the adsorption process, such as adsorbent dosage, initial and equilibrium pH, initial metal concentration and contact time, were analyzed. The maximum removal efficiency were achieved at the level of 99.8% for Pb(II) and 99.6% for Cu(II), respectively. The kinetics analysis and isotherms showed that the pseudo-second-order equation and the Freundlich isotherm models better describe these processes. The experiments proved that SW-FA can act as an appropriate adsorbent for highly effective removal of lead and copper from wastewater and improvement of water quality.

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Influence of MBE Growth Conditions on Dislocation Densities of GaAs/Ge Epilayers Grown on Silicon Substrates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118692 ◽

1985 ◽

Vol 43 ◽

pp. 364-365

Author(s):

K.M. Hones ◽

P. Sheldon ◽

B.G. Yacobi ◽

A. Mason

Keyword(s):

High Efficiency ◽

Lattice Mismatch ◽

Low Cost ◽

Growth Conditions ◽

Nonradiative Recombination ◽

Device Structure ◽

Si Substrates ◽

Transmission Electron ◽

Dislocation Densities ◽

Dislocation Type

There is increasing interest in growing epitaxial GaAs on Si substrates. Such a device structure would allow low-cost substrates to be used for high-efficiency cascade- junction solar cells. However, high-defect densities may result from the large lattice mismatch (∼4%) between the GaAs epilayer and the silicon substrate. These defects can act as nonradiative recombination centers that can degrade the optical and electrical properties of the epitaxially grown GaAs. For this reason, it is important to optimize epilayer growth conditions in order to minimize resulting dislocation densities. The purpose of this paper is to provide an indication of the quality of the epitaxially grown GaAs layers by using transmission electron microscopy (TEM) to examine dislocation type and density as a function of various growth conditions. In this study an intermediate Ge layer was used to avoid nucleation difficulties observed for GaAs growth directly on Si substrates. GaAs/Ge epilayers were grown by molecular beam epitaxy (MBE) on Si substrates in a manner similar to that described previously.

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Improvement of Ti/RuO2–IrO2 Anode Lifetime and Electrocatalytical Properties by Using an Eco-Friendly Thermal Decomposition Method Using Polyvinyl Alcohol as Solvent

10.26434/chemrxiv.7991129 ◽

2019 ◽

Author(s):

Charlys Bezerra ◽

Géssica Santos ◽

Marilia Pupo ◽

Maria Gomes ◽

Ronaldo Silva ◽

...

Keyword(s):

Thermal Decomposition ◽

Polyvinyl Alcohol ◽

High Efficiency ◽

Electrochemical Impedance ◽

Pechini Method ◽

Low Cost ◽

Charge Transfer Resistance ◽

Transfer Resistance ◽

Calcination Temperatures ◽

Service Lifetime

Electrochemical oxidation processes are promising solutions for wastewater treatment due to their high efficiency, easy control and versatility. Mixed metal oxides (MMO) anodes are particularly attractive due to their low cost and specific catalytic properties. Here, we propose an innovative thermal decomposition methodology using <a>polyvinyl alcohol (PVA)</a> as a solvent to prepare Ti/RuO2–IrO2 anodes. Comparative anodes were prepared by conventional method employing a polymeric precursor solvent (Pechini method). The calcination temperatures studied were 300, 400 and 500 °C. The physical characterisation of all materials was performed by X-ray diffraction and scanning electron microscopy coupled with energy dispersive spectroscopy, while electrochemical characterisation was done by cyclic voltammetry, accelerated service lifetime and electrochemical impedance spectroscopy. Both RuO2 and IrO2 have rutile-type structures for all anodes. Rougher and more compact surfaces are formed for the anodes prepared using PVA. Amongst temperatures studied, 300 °C using PVA as solvent is the most suitable one to produce anodes with expressive increase in voltammetric charge (250%) and accelerated service lifetime (4.3 times longer) besides reducing charge-transfer resistance (8 times lower). Moreover, the electrocatalytic activity of the anodes synthesised with PVA toward the Reactive Blue 21 dye removal in chloride medium (100 % in 30 min) is higher than that prepared by Pechini method (60 min). Additionally, the removal total organic carbon point out improved mineralisation potential of PVA anodes. Finally, this study reports a novel methodology using PVA as solvent to synthesise Ti/RuO2–IrO2 anodes with improved properties that can be further extended to synthesise other MMO compositions.

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