High-Resolution SEM and EDX Characterization of Deposits Formed by CH4+Ar DBD Plasma Processing in a Packed Bed Reactor

The deposits formed during the DBD plasma conversion of CH4 were characterized by high-resolution scanning electron microscopy (HRSEM) and energy dispersive X-ray elemental analysis (EDX) for both cases of a non-packed reactor and a packed reactor. For the non-packed plasma reactor, a layer of deposits was formed on the dielectric surface. HRSEM images in combination with EDX and CHN elemental analysis of this layer revealed that the deposits are made of a polymer-like layer with a high content of hydrogen (60 at%), possessing an amorphous structure. For the packed reactor, γ-alumina, Pd/γ-alumina, BaTiO3, silica-SBA-15, MgO/Al2O3, and α-alumina were used as the packing materials inside the DBD discharges. Carbon-rich agglomerates were formed on the γ-alumina after exposure to plasma. The EDX mapping furthermore indicated the carbon-rich areas in the structure. In contrast, the formation of agglomerates was not observed for Pd-loaded γ-alumina. This was ascribed to the presence of Pd, which enhances the hydrogenation of deposit precursors, and leads to a significantly lower amount of deposits. It was further found that the structure of all other plasma-processed materials, including MgO/Al2O3, silica-SBA-15, BaTiO3, and α-alumina, undergoes morphological changes. These alterations appeared in the forms of the generation of new pores (voids) in the structure, as well as the moderation of the surface roughness towards a smoother surface after the plasma treatment.

Download Full-text

The Potential Use of Core-Shell Structured Spheres in a Packed-Bed DBD Plasma Reactor for CO2 Conversion

Catalysts ◽

10.3390/catal10050530 ◽

2020 ◽

Vol 10 (5) ◽

pp. 530

Author(s):

Yannick Uytdenhouwen ◽

Vera Meynen ◽

Pegie Cool ◽

Annemie Bogaerts

Keyword(s):

Energy Efficiency ◽

Plasma Reactor ◽

Spray Coating ◽

Packed Bed ◽

Packed Bed Reactor ◽

Core Material ◽

Core Shell ◽

Co2 Conversion ◽

Dbd Plasma ◽

Specific Material

This work proposes to use core-shell structured spheres to evaluate whether it allows to individually optimize bulk and surface effects of a packing material, in order to optimize conversion and energy efficiency. Different core-shell materials have been prepared by spray coating, using dense spheres (as core) and powders (as shell) of SiO2, Al2O3, and BaTiO3. The materials are investigated for their performance in CO2 dissociation and compared against a benchmark consisting of a packed-bed reactor with the pure dense spheres, as well as an empty reactor. The results in terms of CO2 conversion and energy efficiency show various interactions between the core and shell material, depending on their combination. Al2O3 was found as the best core material under the applied conditions here, followed by BaTiO3 and SiO2, in agreement with their behaviour for the pure spheres. Applying a thin shell layer on the cores showed equal performance between the different shell materials. Increasing the layer thickness shifts this behaviour, and strong combination effects were observed depending on the specific material. Therefore, this method of core-shell spheres has the potential to allow tuning of the packing properties more closely to the application by designing an optimal combination of core and shell.

Download Full-text

Probing the impact of material properties of core-shell SiO2@TiO2 spheres on the plasma-catalytic CO2 dissociation using a packed bed DBD plasma reactor

Journal of CO2 Utilization ◽

10.1016/j.jcou.2021.101468 ◽

2021 ◽

Vol 46 ◽

pp. 101468

Author(s):

Periyasamy Kaliyappan ◽

Andreas Paulus ◽

Jan D’Haen ◽

Pieter Samyn ◽

Yannick Uytdenhouwen ◽

...

Keyword(s):

Material Properties ◽

Plasma Reactor ◽

Packed Bed ◽

Core Shell ◽

Dbd Plasma ◽

The Impact

Download Full-text

Decomposition of Volatile Organic Compounds by a Packed-Bed Reactor and a Pulsed-Corona Plasma Reactor

Non-Thermal Plasma Techniques for Pollution Control ◽

10.1007/978-3-642-78476-7_18 ◽

1993 ◽

pp. 223-237 ◽

Cited By ~ 33

Author(s):

T. Yamamoto ◽

P. A. Lawless ◽

M. K. Owen ◽

D. S. Ensor ◽

C. Boss

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Plasma Reactor ◽

Packed Bed ◽

Packed Bed Reactor ◽

Corona Plasma ◽

Pulsed Corona ◽

Volatile Organic

Download Full-text

Plasma Catalytic Conversion of CH4 to Alkanes, Olefins and H2 in a Packed Bed DBD Reactor

Processes ◽

10.3390/pr8070774 ◽

2020 ◽

Vol 8 (7) ◽

pp. 774

Author(s):

Mohammadreza Taheraslani ◽

Han Gardeniers

Keyword(s):

Barrier Discharge ◽

Plasma Reactor ◽

Packed Bed ◽

Reaction Pathways ◽

Ambient Conditions ◽

Alumina Catalyst ◽

Dbd Plasma ◽

Hydrogenation Reactions ◽

Notable Increase

Methane is activated at ambient conditions in a dielectric barrier discharge (DBD) plasma reactor packed with Pd/γ-alumina catalyst containing different loadings of Pd (0.5, 1, 5 wt%). Results indicate that the presence of Pd on γ-alumina substantially abates the formation of deposits, leads to a notable increase in the production of alkanes and olefins and additionally improves the energy efficiency compared to those obtained for the non-packed reactor and the bare γ-alumina packed reactor. A low amount of Pd (0.5 and 1 wt%) favors achieving a higher production of olefins (mainly C2H4 and C3H6) and a higher yield of H2. Increasing Pd loading to 5 wt% promotes the interaction of H2 and olefins, which consequently intensifies the successive hydrogenation of unsaturated compounds, thus incurring a higher production of alkanes (mainly C2H6 and C3H8). The substantial abatement of the deposits is ascribed to the role of Palladium in moderating the strength of the electric and shifting the reaction pathways, in the way that hydrogenation reactions of deposits’ precursors become faster than their deposition on the catalyst.

Download Full-text

Decomposition of Carbon Tetrachloride by a Packed Bed Plasma Reactor

Journal of Advanced Oxidation Technologies ◽

10.1515/jaots-1997-0213 ◽

1997 ◽

Vol 2 (2) ◽

Cited By ~ 1

Author(s):

G. Prieto ◽

O. Prieto ◽

C. R. Gay ◽

K. Mizuno ◽

I. Tamori ◽

...

Keyword(s):

Carbon Tetrachloride ◽

Plasma Reactor ◽

Packed Bed ◽

Operating Conditions ◽

Empirical Modeling ◽

Atmospheric Pollutants ◽

Packed Bed Reactor ◽

Volatile Organic ◽

Reactor Operating ◽

Decomposition Efficiency

AbstractIn search of a technology capable of controlling atmospheric pollutants, like volatile organic compounds (VOCs) in low concentrations, this paper is concerned with the empirical modeling of a ferroelectric plasma packed-bed reactor at ambient temperature and pressure. The empirical model gives information about the decomposition efficiency of the process as a function of the reactor operating variables. The volatile organic compound selected is Carbon Tetrachloride balanced with air in the concentration-range of 150 to 600 ppm and flow-range of 175 to 325 ml/min. Regarding the decomposition efficiency as the objective function, this modeling provides valuable information about the optimal operating conditions.

Download Full-text

Removal of sulfur dioxide from air using a packed-bed DBD plasma reactor (PBR) and in-plasma catalysis (IPC) hybrid system

Environmental Science and Pollution Research ◽

10.1007/s11356-021-13173-5 ◽

2021 ◽

Author(s):

Niloofar Damyar ◽

Ali Khavanin ◽

Ahmad Jonidi Jafari ◽

Hassan Asilian Mahabadi ◽

Ramazan Mirzaei ◽

...

Keyword(s):

Sulfur Dioxide ◽

Hybrid System ◽

Plasma Reactor ◽

Packed Bed ◽

Plasma Catalysis ◽

Dbd Plasma

Download Full-text

Coupling of CH4 to C2 Hydrocarbons in a Packed Bed DBD Plasma Reactor: The Effect of Dielectric Constant and Porosity of the Packing

Energies ◽

10.3390/en13020468 ◽

2020 ◽

Vol 13 (2) ◽

pp. 468 ◽

Cited By ~ 5

Author(s):

Mohammadreza Taheraslani ◽

Han Gardeniers

Keyword(s):

Dielectric Constant ◽

Strong Electric Field ◽

Plasma Reactor ◽

Packed Bed ◽

Ambient Conditions ◽

Dbd Plasma ◽

Low Dielectric ◽

Small Pore ◽

High Dielectric ◽

C2 Hydrocarbons

The conversion of methane was investigated in a packed-bed dielectric barrier discharge (DBD) plasma reactor operated at ambient conditions. High dielectric BaTiO3 was utilized as packing in comparison with γ-alumina, α-alumina, and silica-SBA-15. Results show a considerably lower conversion of CH4 and C2 yield for the BaTiO3 packed reactor, which is even less than that obtained for the nonpacked reactor. In contrast, the low dielectric alumina (γ and α) packed reactor improved the conversion of CH4 and C2 yield. Additionally, the alumina packed reactor shifted the distribution of C2 compounds towards C2H4 higher than that obtained for the nonpacked reactor and resulted in a higher energy efficiency compared to the BaTiO3 packed reactor. This is attributed to the small pore size of BaTiO3 (10–200 nm) and its high dielectric constant, whereas the polarization inside small pores does not lead to the formation of an overall strong electric field.

Download Full-text