Influence of the operating conditions on the production rate of multi-walled carbon nanotubes in a CVD reactor

Absrtract. In this paper, the method of ultrasonic vibration in preparation of multi-walled carbon nanotubes(MWCNTs)/epoxy resin composites was studied. Suspension specimens of MWCNTs/epoxy resin solution prepared by different ultrasonic conditions were compared to find out the influences of operating conditions on dispersion properties. In this study, transmission electron microscopes(TEM) were used to characterize the morphology of the blends and suspension stability was used to evaluate the stability of blends. The results showed that ultrasonic power, ultrasonic time and material quantity have great effect on the dispersion of MWCNTs in epoxy resin solution. Increasing ultrasonic power and time can improve dispersion of MWCNTs, and decreasing material quantity within an appropriate range was helpful to disperse MWCNTs into epoxy resin solution. The results of suspension stability were very similar with TEM results, which demonstrate that suspension stability of MWCNTs/epoxy resin blending could be used as an assistant method to characterize the dispersion of MWCNTs in epoxy resin.

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Effect of Operating Conditions for Higher Alcohols Synthesis from Synthesis Gas over Alkali-Modified Co-Rh-Mo Trimetallic Catalyst Supported on Multi-Walled Carbon Nanotubes

International Journal of Chemical Reactor Engineering ◽

10.1515/1542-6580.2697 ◽

2011 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Venkateswara Rao Surisetty ◽

Janusz Kozinski ◽

Ajay K. Dalai

Keyword(s):

Carbon Nanotubes ◽

Synthesis Gas ◽

Fixed Bed ◽

Operating Conditions ◽

Fixed Bed Reactor ◽

Optimum Operating ◽

Higher Alcohols ◽

Higher Alcohols Synthesis ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

The effects of operating conditions on the higher alcohols synthesis reaction from synthesis gas were studied in a single-pass tubular downflow fixed-bed reactor, using sulfided K-promoted trimetallic Co-Rh-Mo catalyst supported on multi-walled carbon nanotubes (MWCNTs). The p CO conversion increased monotonically with increasing reaction temperature (from 275 to 350°C) and pressure (from 800 to 1400 psi), while decreasing monotonically with increasing GHSV (from 2.4 to 4.2 m3 (STP)/(kg of cat./h)). To maximize the ethanol STY and selectivity, the optimum operating conditions were determined as 330°C, 1320 psi, and 3.8 m3 (STP)/kg of cat./h). Maximum ethanol STY and selectivity were obtained using gas with H2 to CO molar ratio around 1.25.

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Carbon Nanotubes for Removal of Fast Green Dye

International Research Journal of Pure and Applied Chemistry ◽

10.9734/irjpac/2020/v21i530168 ◽

2020 ◽

pp. 25-35

Author(s):

Haydar A. Mohammad-Salim ◽

Sabir Ayob Mohammed Salih ◽

Mohammed Mahmoud Molla-Babaker

Keyword(s):

Carbon Nanotubes ◽

Dye Removal ◽

Langmuir Equation ◽

Operating Conditions ◽

Fast Green ◽

Adsorption Data ◽

Multi Walled Carbon Nanotubes ◽

Analysis Of Results ◽

Walled Carbon Nanotubes ◽

Langmuir And Freundlich Models

The adsorption of Fast Green (FG) dye on pristine multi-walled carbon nanotubes (CNTs) was investigated in this study. The adsorption was carried out under different operating conditions. The operating conditions were contact time, adsorbent dosage, initial dye concentration, the pH of the solution and temperature. The analysis of results found that the removal percentage of FG dye on CNTs decreases with increase in initial FG concentration. It was found that the increasing of CNTs dosage enhanced the efficiency of dye removal. It was also found that the increasing of temperature significantly enhanced the removal percent of FG dye and it is indicated that the adsorption of FG dye on CNTs was in endothermic nature. The study reports that the best pH of solution for the adsorption of FG on CNTs were 4. The adsorption data have been analyzed using Langmuir and Freundlich. Fitting the equilibrium adsorption data by Langmuir and Freundlich models shows that experimental data well explained by the Langmuir equation.

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A novel design for mass production of multi-walled carbon nanotubes using Co-Mo/MgO catalyst via pyrolysis of polypropylene waste: effect of operating conditions

Fullerenes Nanotubes and Carbon Nanostructures ◽

10.1080/1536383x.2018.1476344 ◽

2018 ◽

Vol 26 (9) ◽

pp. 591-605 ◽

Cited By ~ 6

Author(s):

Ateyya A. Aboul-Enein ◽

Ahmed E. Awadallah

Keyword(s):

Carbon Nanotubes ◽

Mass Production ◽

Operating Conditions ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes ◽

Novel Design

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Effect of Operating Conditions for Higher Alcohols Synthesis from Synthesis Gas over Alkali-Modified Co-Rh-Mo Trimetallic Catalyst Supported on Multi-Walled Carbon Nanotubes

nano Online ◽

10.1515/nano.0019.00017 ◽

2016 ◽

Author(s):

Venkateswara Rao Surisetty ◽

Janusz Kozinski ◽

Ajay K. Dalai

Keyword(s):

Carbon Nanotubes ◽

Synthesis Gas ◽

Operating Conditions ◽

Higher Alcohols ◽

Trimetallic Catalyst ◽

Higher Alcohols Synthesis ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

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The sum is more than its parts: stability of MnFe oxide nanoparticles supported on oxygen-functionalized multi-walled carbon nanotubes at alternating oxygen reduction reaction and oxygen evolution reaction conditions

Journal of Solid State Electrochemistry ◽

10.1007/s10008-020-04667-2 ◽

2020 ◽

Vol 24 (11-12) ◽

pp. 2901-2906

Author(s):

Dulce M. Morales ◽

Mariya A. Kazakova ◽

Maximilian Purcel ◽

Justus Masa ◽

Wolfgang Schuhmann

Keyword(s):

Carbon Nanotubes ◽

Oxygen Reduction ◽

Oxygen Evolution ◽

Active Sites ◽

Reduction Reaction ◽

Operating Conditions ◽

Active Components ◽

Successful Design ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

Abstract Successful design of reversible oxygen electrocatalysts does not only require to consider their activity towards the oxygen reduction (ORR) and the oxygen evolution reactions (OER), but also their electrochemical stability at alternating ORR and OER operating conditions, which is important for potential applications in reversible electrolyzers/fuel cells or metal/air batteries. We show that the combination of catalyst materials containing stable ORR active sites with those containing stable OER active sites may result in a stable ORR/OER catalyst if each of the active components can satisfy the current demand of their respective reaction. We compare the ORR/OER performances of oxides of Mn (stable ORR active sites), Fe (stable OER active sites), and bimetallic Mn0.5Fe0.5 (reversible ORR/OER catalyst) supported on oxidized multi-walled carbon nanotubes. Despite the instability of Mn and Fe oxide for the OER and the ORR, respectively, Mn0.5Fe0.5 exhibits high stability for both reactions.

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Electrochemical Method for Ease Determination of Sodium Diclofenac Trace Levels in Water Using Graphene—Multi-Walled Carbon Nanotubes Paste Electrode

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph19010029 ◽

2021 ◽

Vol 19 (1) ◽

pp. 29

Author(s):

Sorina Motoc ◽

Florica Manea ◽

Anamaria Baciu ◽

Corina Orha ◽

Aniela Pop

Keyword(s):

Carbon Nanotubes ◽

Limit Of Detection ◽

Tap Water ◽

Operating Conditions ◽

Carbon Nanotubes Paste Electrode ◽

Sodium Diclofenac ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes ◽

Paste Electrode

Sodium diclofenac (DCF) presence reported in water use cycle at various concentrations including trace levels necessitates continuous development of advanced analytical method for its determination. In this work, ease electrochemical methods for DCF determination based on voltammetric and amperometric techniques were proposed using a simple combination of graphene with multi-walled carbon nanotubes as paste electrode. Integration of the graphene with multi-walled carbon nanotubes enlarged the electroactive surface area of the electrode and implicitly enhanced the electrochemical response for DCF determination. On the basis of the sorption autocatalytic effect manifested at low concentration of DCF, we found that the preconcentration step applied prior to differential-pulsed voltammetry (DPV) and multiple-pulsed amperometry (MPA) allowed for the enhancement of the electroanalytical performance of the DCF electrochemical detections, which were validated by testing in tap water. The lowest limit of detection (LOD) of 1.40 ng·L−1 was found using preconcentration prior to DPV under optimized operating conditions, which is better than that reached by other carbon-based electrodes reported in the literature.

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