• Applied Chemistry for Engineering
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• v.33 no.2
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• pp.229-233
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• 2022

In this study, a gas-liquid hybrid atmospheric pressure plasma reactor of the dielectric barrier discharge method was fabricated and characterized. The solubility of copper oxide in the organic acid solution was increased when argon having a larger atomic weight than helium was used during plasma discharge. There was no significant effect of mixing organic acid solutions under plasma discharge treatment on the variation of copper oxide's solubility. As the applied voltage for plasma discharge and the concentration of the organic acid solution increased, the dissolution and removal power of the copper oxide layer increased. Solubility of copper oxide was more affected by the concentration in organic acid solution rather than the variation of plasma applied voltage. The usefulness of hybrid plasma reactor for the surface cleaning process was confirmed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.2
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• pp.128-133
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• 2000

Numerical analysis of the transport phenomena in an inductively coupled plasma reactor was conducted with two-dimensional axisymmetric model including the electromagnetic field model, electron and species density models. The spatial distribution of the charged species in the ion flux to the wafer have been calculated to examine the influence of the process conditions including antenna and reactor geometry. The antenna radius had a significant influence on the plasma state and axial ion flux distribution.

• Resources Recycling
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• v.13 no.1
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• pp.59-67
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• 2004

A universal plasma-chemical module (PChM) for the industrial processing of different hydrocarbon raw material pyrolysis was designed and tested. Laboratory investigations for the plasma-chemical method of acetylene production from natural gas and different coals were made. Similar laboratory tests on the industrial production of acetylene as a raw material for organic syn-thesis were developed using the PChM. A comparison of the suggested plasma-chemical method with the traditional process of acetylene production were carried out. The outlook of the plasma-chemical method was shown.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.343-347
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• 2012

The decomposition behaviors of gaseous cyanides in non-thermal plasma-catalyst hybrid reactor have been investigated with the variation of discharge power, influent concentration of cyanide, humidity of air carrier and packed materials in the reactor. Destruction of cyanides by plasma only process was very difficult compared to that of trichloroethylene. But the destruction efficiencies of cyanides were dramatically improved through packing alumina or Pt/alumina bead in the plasma discharge region. From the results, it could be assumed that thermal catalytic effect is involved simultaneously with plasma in the reaction of cyanides destruction on the alumina or Pt/alumina packed plasma reactor.

• Journal of the Korean Society of Safety
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• v.15 no.3
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• pp.66-70
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• 2000

In order to cope with environmental problems caused by harmful gases emitted from various industrial sources, a new technology which employs discharge plasma formed in ordinary atmospheric pressure has been intensively investigated in many industrialized nations. Although a plenty of useful outcomes and suggestions have been made public by scientists in this field, few commercial products which effectively decompose pollutant gases have appeared as yet. This is partly because that the energy efficiency of a most effective plasma reactor has not reached a satisfactory level in comparison with those of devices using conventional technologies. In an attempt to solve the problem mentioned above, we noticed to combine heterogeneous electrical discharges. This concepts is based on that each plasma reactor has its specific spatial region in which chemical reaction are active and by electrically affected with another reactor of different type, the activated region would increase - which may lead to cutting down the energy consumption. To prove this concept experimentally, two different discharge equipments, a plane ceramic-based surface discharge electrode and a corona electrode with tungsten needle may, are selected and combined to fabricate a hybrid plasma reactor. The results are summarized as follows; (1) Ozone concentration generated in the plasma region drastically increases when the positive corona discharge is added to the surface discharge. The rate of increase of ozone depends on the frequency of the surface discharge. The negative corona, however, does not contribute to the improvement of the ozone generation. (2) NO(nitrogen monoxide) decomposition rate also improves by simultaneously applying the surface and the positive corona discharges. The effect of the corona superposition is more evident when the level of the surface discharge is moderate. (3) By adjusting the corona level, the net energy efficiency during NO decomposition improves in comparison with the simple surface discharge reactor.

• Journal of Industrial Technology
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• v.14
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• pp.63-75
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• 1994

The objective of this research is to analyze the phenomena of negative ion behavior in silane plasma chemical vapor deposition. Based on the plasma chemistry, the model equations for the formation and transport of negative ions were proposed and solved. The evolutions of gaseous species along the reactor were presented for several conditions of process variables such as reactor pressure, total gas flow rate, and electric field. Based on the model results, it is found that : (1) The concentration profiles of positive ions show the sharp peaks at the center of plasma reactor. (2) Most of negative ions are located in bulk plasma region, because the negative ions are excluded from the sheath region by electrostatic repulsion.

• Korean Chemical Engineering Research
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• v.60 no.3
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• pp.452-458
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• 2022

Three types of gas-liquid hybrid horizontal, vertical and needle-to-cylinder plasma reactors were fabricated. Through these reactors, a high-efficiency, eco-friendly cleaning concept that generates reactive active species generated in atmospheric plasma discharge and gas-liquid activation reaction of cleaning components through the potential difference within the electrode was presented. As a result of comparing the efficiency for cleaning performance, the needle-to-cylinder type reactor had the best characteristics. Through this study, it was confirmed that the gas-liquid hybrid atmospheric pressure plasma reactor has the potential to be applied to ultra-precision cleaning processes such as semiconductor processes.

• Journal of the Korean Society of Safety
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• v.14 no.3
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• pp.63-68
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• 1999

In this paper, characteristics of ozone generation by using coil and SPCP + DC corona reactor was studied. The ceramic-based surface discharge electrode, which was first invented as a high-efficiency ozonizer, has been used as an experimental plasma chemical reactor.(Surface Induced Plasma Chemical Processing, SPCP.) The electrode, however, has a structural disadvantage that a highly energetic plasma region is localized near the electrode surface, which may make it impossible for higher efficiency to realize. In an attempt to overcome this advantage, we have developed a hybrid reactor which employs a corona discharge unit together with the surface discharge unit. Experimental results suggest that the efficiency of the ozone production rate is improved when positive corona discharge is added.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1869-1873
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• 2008

In this work, to make it possible to generate glow discharge in atmospheric pressure condition with relatively high and wide electric field, micro channel reactor is proposed. Si DRIE and Cr deposition by Ebeam evaporation is used to make channel and bottom electrode layer. Upper electrode is made from ITO glass to visualize discharge within micro channel. Fabricated reactor is verified by generating uniform glow plasma with N2 / He gases each as working fluid. The range of gas electric field to generate glow plasma is from about 200 V/cm and upper limit is not observed in tested condition of up to 150 kV/cm. This data shows that micro channel plasma reactor is more versatile. Indirect estimation of electron temperature in this reactor can be inferred that the electron temperature within glow discharge in micro reactor lies $0{\sim}2eV$. This research demonstrates that the reactor is appropriate in application that needs to maintain low temperature condition during chemical process.

• Applied Chemistry for Engineering
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• v.25 no.5
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• pp.497-502
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• 2014

The conversion reaction of methane and carbon dioxide at an atmospheric pressure plasma reactor filled with Ni-$Al_2O_3$ and Ni-$MgAl_2O_4$ catalyst was performed. Effects of various process parameters such as the applied electric power, reaction gas flow rate, reactor temperature, mixing ratio of reactants and the presence of the catalyst on the reaction between methane and carbon dioxide were analyzed. From the analysis of the contribution of the catalyst in the reaction step, even if the temperature raised to $400^{\circ}C$, there was no spontaneous catalytic conversion of methane and carbon dioxide without plasma discharges. When the catalysts for the conversion of methane and carbon dioxide would be adopted to the plasma reactor, the careful selection of suitable catalysts and process parameters should be essential.