The Influence of Fe/Al Molar Ratio on Microreactor-Based Catalyst Preparation and Carbon Nanotube Preparation

In order to prepare carbon nanotubes with high specific surface area, small diameter, low resistivity, high purity and high catalytic activity, the Fe-Mo/Al2O3 catalyst was prepared based on the microreactor. The influence of different Fe/Al molar ratios on the catalyst and the carbon nanotubes prepared was studied through BET, SEM, TEM and other detection methods. Studies have shown that the pore structure of the catalyst is dominated by slit pores at a lower Fe/Al molar ratio. The catalytic activity is the highest when the Fe/Al molar ratio is 1:1, reaching 74.1%. When the Fe/Al molar ratio is 1:2, the catalyst has a higher specific surface area, the maximum pore size is 8.63 nm, and the four-probe resistivity and ash content of the corresponding carbon nanotubes are the lowest. The higher the proportion of aluminum, the higher the specific surface area of the catalyst and the carbon nanotubes, and the finer the diameter of the carbon nanotubes, which gradually tends to relax. The results show that when the Fe/Al molar ratio is 1:2, although the catalytic activity of the catalyst is not the highest, the carbon nanotubes prepared have the best performance.

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High specific surface area carbon nanotubes from catalytic chemical vapor deposition process

Chemical Physics Letters ◽

10.1016/s0009-2614(00)00558-3 ◽

2000 ◽

Vol 323 (5-6) ◽

pp. 566-571 ◽

Cited By ~ 128

Author(s):

R.R. Bacsa ◽

Ch. Laurent ◽

A. Peigney ◽

W.S. Bacsa ◽

Th. Vaugien ◽

...

Keyword(s):

Carbon Nanotubes ◽

Chemical Vapor Deposition ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Vapor Deposition ◽

Chemical Vapor ◽

Deposition Process ◽

High Specific Surface Area ◽

Catalytic Chemical Vapor Deposition

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Frontiers of carbon materials as capacitive deionization electrodes

Dalton Transactions ◽

10.1039/d0dt00684j ◽

2020 ◽

Vol 49 (16) ◽

pp. 5006-5014 ◽

Cited By ~ 4

Author(s):

Yuanyuan Li ◽

Nan Chen ◽

Zengling Li ◽

Huibo Shao ◽

Liangti Qu

Keyword(s):

Carbon Nanotubes ◽

Activated Carbon ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Carbon Materials ◽

High Specific Surface Area ◽

Carbon Aerogels ◽

Capacitive Deionization

Carbon materials are widely used as capacitive deionization (CDI) electrodes due to their high specific surface area (SSA), superior conductivity, and better stability, including activated carbon, carbon aerogels, carbon nanotubes and graphene.

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Preparation, characterization and catalytic properties of yttrium-zirconium-pillared montmorillonite and their application in supported Ce catalysts

Clay Minerals ◽

10.1180/claymin.2015.050.2.05 ◽

2015 ◽

Vol 50 (2) ◽

pp. 211-219 ◽

Cited By ~ 5

Author(s):

Bo Xue ◽

Hongmei Guo ◽

Lujie Liu ◽

Min Chen

Keyword(s):

Catalytic Activity ◽

Ethyl Acetate ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Active Sites ◽

Industrial Applications ◽

High Catalytic Activity ◽

Total Oxidation ◽

Pillared Montmorillonite

AbstractA new yttrium-zirconium-pillared montmorillonite (Y-Zr-MMT), was synthesized, characterized and used as a Ce catalyst support. The Y-Zr-MMT is a good support for dispersing cerium active sites and it is responsible for the high activity in the total oxidation of acetone, toluene and ethyl acetate. The Y-Zr-MMT shows greater advantages than the conventional alumina/cordierite honeycomb supports such as large specific surface area, lower cost and easier preparation. Catalytic tests demonstrated that Ce/Y-Zr-MMT (Ce loading 8.0%) was the most active, with the total oxidation of acetone, toluene and ethyl acetate being achieved at 220, 300 and 220°C, respectively. The catalyst displayed better activity for the oxidation of acetone and ethyl acetate than a conventional, supported Pd-catalyst under similar conditions. The special structure of the yttrium-doped zirconium-pillared montmorillonite can strengthen the interaction between the CeO2 and Zr-MMT support and improve the dispersion of the Ce particles, which enhances the catalytic activity for the oxidation of VOCs. The new catalyst, 8.0%Ce/Y-Zr-MMT, could be promising for industrial applications due to its high catalytic activity and low cost. The support and the catalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and BET specific surface area measurements.

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Preparation and Characterization of Ultralow Density Silica Aerogels by Acetonitrile Supercritical Drying

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.519.83 ◽

2012 ◽

Vol 519 ◽

pp. 83-86 ◽

Cited By ~ 6

Author(s):

Guang Wu Liu ◽

Xing Yuan Ni ◽

Bin Zhou ◽

Qiu Jie Yu

Keyword(s):

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Silica Aerogel ◽

Sol Gel ◽

Supercritical Drying ◽

Silica Aerogels ◽

High Specific Surface Area ◽

Molar Ratio ◽

Sol Gel Process

This paper deals with the synthesis of ultralow density silica aerogels using tetramethyl orthosilicate (TMOS) as the precursor via sol-gel process followed by supercritical drying using acetonitrile solvent extraction. Ultralow density silica aerogels with 6 mg/cc of density was made for the molar ratio by this method. The microstructure and morphology of the ultralow density silica aerogels was characterized by the specific surface area, SBET, SEM, and the pore size distribution techniques. The results show that the ultralow density silica aerogel has the high specific surface area of 812m2/g. Thermal conductivities at desired temperatures were analyzed by the transient plane heat source method. Thermal conductivity coefficients of silica aerogel monoliths changed from 0.024 to 0.043W/ (m K) as temperature increased to 400°C, revealed an excellent heat insulation effect during thermal process.

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Synthesis and Structural Characterization of SiO2-Al2O3 Xerogels

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.2286 ◽

2007 ◽

Vol 336-338 ◽

pp. 2286-2289

Author(s):

Fei He ◽

Xiao Dong He ◽

Yao Li

Keyword(s):

Structural Change ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Sol Gel ◽

Nitrogen Adsorption ◽

Mesoporous Structure ◽

Supercritical Drying ◽

High Specific Surface Area ◽

Molar Ratio

Low-density xSiO2-(1-x)Al2O3 xerogels with x=0.9, 0.8, 0.7, 0.6 (mole fractions) were prepared by sol-gel and non-supercritical drying. Silica alkogels, which were the framework of binary composite materials, formed from tetraethyl orthosilicate (TEOS) by hydrolytic condensation with a molar ratio of TEOS: H2O: alcohol: hydrochloric acid: ammonia =1: 4: 10: 7.5×10-4: 0.0375. Aluminum hydroxide derived from Al(NO3)3·9H2O and NH4OH acting in the alcohol solution under the condition of catalyst. After filtrating and washing, the precipitation was mixed into silica sols to form SiO2-Al2O3 mixed oxide gels with different silicon and aluminum molar ratio. The structural change and crystallization of the binary xerogels were investigated after heat treatment at 600 for 2 h by the means of X-ray diffraction. Nitrogen adsorption experiment was performed to estimate specific surface area, porous volume and pore size distribution. The structural change of xerogels was observed by FT-IR spectroscopy. The resulting mixed xerogels possess of mesoporous structure which is characteristic of cylindrical pores, high specific surface area of 596-863 m2/g and a relatively narrow pore distribution of 2.8-30 nm. Al2O3 is introduced into the SiO2 phase and some of Al-O-Si bonds form.

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High-Level Oxygen Reduction Catalysts Derived from the Compounds of High-Specific-Surface-Area Pine Peel Activated Carbon and Phthalocyanine Cobalt

Nanomaterials ◽

10.3390/nano11123429 ◽

2021 ◽

Vol 11 (12) ◽

pp. 3429

Author(s):

Lei Zhao ◽

Ziwei Lan ◽

Wenhao Mo ◽

Junyu Su ◽

Huazhu Liang ◽

...

Keyword(s):

Activated Carbon ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Active Sites ◽

High Performance ◽

Low Cost ◽

Specific Area ◽

High Specific Surface Area ◽

High Catalytic Activity

Non-platinum carbon-based catalysts have attracted much more attention in recent years because of their low cost and outstanding performance, and are regarded as one of the most promising alternatives to precious metal catalysts. Activated carbon (AC), which has a large specific surface area (SSA), can be used as a carrier or carbon source at the same time. In this work, stable pine peel bio-based materials were used to prepare large-surface-area activated carbon and then compound with cobalt phthalocyanine (CoPc) to obtain a high-performance cobalt/nitrogen/carbon (Co-N-C) catalyst. High catalytic activity is related to increasing the number of Co particles on the large-specific-area activated carbon, which are related with the immersing effect of CoPc into the AC and the rational decomposed temperature of the CoPc ring. The synergy with N promoting the exposure of CoNx active sites is also important. The Eonset of the catalyst treated with a composite proportion of AC and CoPc of 1 to 2 at 800 °C (AC@CoPc-800-1-2) is 1.006 V, higher than the Pt/C (20 wt%) catalyst. Apart from this, compared with other AC/CoPc series catalysts and Pt/C (20 wt%) catalyst, the stability of AC/CoPc-800-1-2 is 87.8% in 0.1 M KOH after 20,000 s testing. Considering the performance and price of the catalyst in a practical application, these composite catalysts combining biomass carbon materials with phthalocyanine series could be widely used in the area of catalysts and energy storage.

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