50(1)-02.fm

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1 Printed in the Republic of Korea 글로우방전을이용한고효율공기정화용화학반응기의특성관찰에관한연구 ½»y*, Á y, Á û w œ»» l û w yw û w y œw ( ) Study on High Degree of Efficiency Chemical Reactor for Air Purification Using the Glow Discharge Ki-Ho Kim*,, Min-Ho Boo,, and Sang Chun Lee Department of Chemistry, Kyungnam University, Masan , Korea The Center for Instrumental Analysis in Kyungnam University, Masan , Korea Division of Environmental Engineering, Masan , Korea (Received March 22, 2005). w yw»» mx w. Ÿw w y e xƒš,,, t š k»» mw w» ƒ š. w» 1 p w m x y w. ù 1993 v 2-3 w» ƒ w ƒ t, w œ» w w w ƒ SO 2 NO ƒ ƒ w š š. 4 k œ» v x mx, œ»ƒ (Negative glow) m w šz» w. x w x w w» œw w. :, yw»,, œ» v, ABSTRACT. For the basic model of chemical reactor using glow discharge, we used cathode discharge cell with vacant cavity in the middle. Currently glow discharge is widely studied as a radiation source or atomization device in atomic spectroscopy and remarkable technological achievements are made through the graft with other analysis devices such as microanalysis and steel analysis. 1 Additionally, as the characteristics of basic glow discharge and radiation have been reviewed many times, those results could be used in this experiment. 2-3 In 1993, an article regarding the treatment of poisonous gas in the air using low temperature plasma was published. According to this article, if DC Glow Discharge is used under continuous atmospheric flow, poisonous gases such as SO 2 and NO can be removed. 4 Based on those findings, we designed highly efficient reactor where stable air plasma is composed and all air flow pass the negative glow area passing through the tube. It was observed that the cathode tube type glow discharge developed in this study would be economical, easy to use and could be used as radiation source as well. Keywords: Glow Discharge, See-through Hollow Cathode, Chemical Reactor, Air Plasma, Negative Glow 14

2 w šz œ» y yw» p w 15 ú x w w w y wš ù š ƒ y» jš. w l w p w yw sƒ š y x wyw w m w wš w ƒ š, y v w z wš w š. v w š k y k,, w» w» k š w. v k p ù p w w v, k w v, d v, v, v w. wš w v,» w x w J. W. Hittorf(1824~1919), š H. Geissler(1814~1879) w. 20» J. S. E. Townsend(1868~1957) F. Paschen(1865~1947) w x (Glow Discharge System: GDS) w ƒ. x w» w œ» y yw» ww» p š w. x p ƒ w š Bx(Fig. 3) mx mw œ» w w wyw (Dimethylmethyl-phosphonate (DMMP)) z x mw 99.9% y. Bx w v 2.5 l/ min œ»,» Ax w 2 w. Bx w rp Fig. 1. Schematic diagram of the experimental apparatus. Fig. 2. Schematic diagram of a type chemical reactor.

3 16 ½»yÁ yá» 1 l/min, w Ax(0.3 l/min) w 2.5. x,» Fig. 1 v (Direct current - Glow Discharge Plasma) x e ùkü, Fig. 2, Fig. 3 œ» y yw» ü y w. ƒ ƒ k w ü (Cathode Dark Space) w, (Negative Glow) ü w œ» yw. yw» e œ» w ƒ w, œ» 1000 ml/min f œ» v rp w (Dark Space)ƒ f w w œ» v ƒ. A B x w p He Ar Air v d Bx» w wyw z GC-MS x mw œ» y yw» p w r. Ax» p (Fig. 2) Ax» r 12.7 mm, ü 6.45 mm l w ƒœ w, AISI 316 l w. AISI 316 l Fe 79%, Cr 18%, Ni 8%, Mo 3%» o½ w w. 5 yƒ Ta ƒ ƒ x ww w. w ƒœ ƒ wš x ƒœ ù (Machinable Alumina).» œ» ew (Needle valve) Dwyer 0~2.5 l/min (Model RMA-14-ssv) w š 6.45 mm l w œ» w w. œ» v ¼ x z y mw d ƒ w,» ¼ w. Bx» p (Fig. 3) Fig. 3 ùkü Bx» 6.45 mm ANSI 316 l w ü 4.20 mm. w Fig. 3. Schematic diagram of B type chemical reactor.

4 w šz œ» y yw» p w 17 ANSI 316 l ƒœw š, ƒœ ù(machinable Alumina) w w ó w (3.1 mm) w w w w. (3.1 mm) š xk š. ANSI 316 l ü 10.0 mm š 12.7 mm ¼ 78 mm ƒœw. Ax ƒ» (Needle valve) Dwyer 0~2.5 l/min (Model RMA-14-ssv) w š 6.45 mm l w œ» w w.» œ» m w w z ƒ ù, ƒ v x jš, œ»ƒ v m j» w. w 2z ù w v w yw sw œ» 1 k z 2 v m w wyw v œ» m j» w. Bx Ax 2 œ» v w x.»» w w e(ksc) œ e (0~200mA, 2KV Max.) w. œ w œ l k œrv(model V-180, Max. 180 l/min for air) w, œ d Varian œ (Type 0531) œ e(vacuum Gauge Meter(Model 803)) w. (Window) q w ƒ w q rp wš w. mw ù Oriel Instruments y e(model 77220) 1024line/mm Ÿ (Photo Diode Array, Oriel Co. Model 77112)» w w. q š w 25 µm w. (Diode Array) w rp y d ƒ w. vp Instaspec Fig. 4. Selected wavelengths of nitrogen emission peak.

5 18 ½»yÁ yá V. 2.0 w l, w. w He, Ar v d œ» y w mx xk w» p x He, Ar v d k - (Einstein-Boltzmann). Ln(I pqλ/g pa pq)=-e p/kt exc +C Ln(I pqλ/g pa pq) X, E p Y w 1 š l»» -1/kT w T exc w. d š y ù gf x, w» w. x Fe 370~380 nm vj w. y ù gf y š w d vj w. 6-7 Fig. 4 x œ» r p nm w w š, Table 1 d w q, y, ùkü. 8 d w» w x»» Table 2 ùkü.» x w ƒ š š x ƒ Table 1. Wavelengths, excitation energies and transition probabilities of neutral iron used for excitation temperature measurement Excitation energy Ep (cm 1 ) Transition Probability ga w. l Oriel instaspec v 5 Acton Research Spectra Drive Stepping Motor Scan Controller Acton Research y e/ rp v(spectrograph), Oriel CCD» w. œ rv 60 l/min Alcatel. cit. w. œ š, x 10 torr xw. š 250 ma~800 ma¾ 50 ma ƒ j d w, x 100 ma~900 ma ¾ 50 ma ƒ j d w. w 370~380 nm w 10 w. š Wavelength λ (nm) w yw» Table 2. Instruments and components for direct-current hollow cathode and anode glow discharge chemical reactor Instrument/component Manufacturer CCD detector: model Spectra Drive stepping motor scan controller Spectrometer: 0.5m, 2400 G/mm -1 grating Software: Instaspec 5 PC computer Vacuum gauge: model 127AA Vacuum Pump: Direct Drive 60 l/min Flow gas: Ultra high purity Ar and He gas DC Power supply: Power output 2.0 kw) Cathode: 1/4 AISH 316 Stainless Steel Tube Anode: 1/2 Stainless Steel Tube ORIEL Co. Acton Research Co. Acton Research Co. ORIEL Co. IBM MKS Co. ALCATEL. CIT. Korea Switching Co. Laboratory made Laboratory made

6 w šz œ» y yw» p w 19 Fig. 5. Voltage value depend on current. œ» œ» œ» v y, š yw» ü v w. xk Fig. 4 x œ» rp nm w w (B 3II[0] C 3II[0]) š. z» w (Grimm) xk s q w û w w š š. 9 w ü x - l 10 Fig. 5 20~140mA w (V). Ax Bx ƒ ƒ ƒw wì ƒ x w. Bx y ƒƒ w. ƒ xk j (Abnormal Glow Discharge) 11 y w š ƒ w v. wr w Ax Bx û v ƒ. Ax œ»» 440 V, 20 ma Bx û 380 V 20 ma œ» v ƒ. œ» xk œ» y» w Fig. 6 Ax w œ» Fig. 6. Emission intensity value depend on curren Fig. 7. Emission intensity value depend on flow rate in B type. 200 ml/min 1000 ml/min ¾ ƒƒ 100 ml/min ƒ g» y w. œ» v ü w 300 ml/min. w r Fig. 7 Bx w œ» 200 ml/min 2000 ml/min ¾ ƒƒ 100 ml/ min ƒ g»ƒ w Ax w 300 ml/min 700 ml/min l 900 ml/ min¾ 2.5 l/min œ» yw., xk» Fig. 8 w œ» 20 ma l 200 ma¾ y j» y r. Ax 200 ml/ min œ» y 100 ma»ƒ ƒw y w. œ» 500 ml/min 1000 ml/min ƒ g w 200 maƒ

7 20 ½»yÁ yá 60 ma¾ ü (Cathode Dark Space) w x x w. x mw Ax Bx œ»ƒ v x w. Fig. 8. Emission intensity value depend on flow rate in A type. w w x w w. Bx 200 ml/min 2500 ml/min¾ y ƒ ƒw w. Bx Ax 2500 ml/min œ» v ƒ w É. p Ax 1500 ml/min v Bx 2500 ml/min. y œ» v Bx 1000 ml/min» 20 ma w v x w ƒ 40 ma w v x w. ù ü ü (Cathode Dark Space)ƒ y ùkû w. w x 100 ma ùkù 120 ma ü ü (Cathode Dark Space) w š v ml/min» w v x w» w 60 ma ƒ v w, ü ü (Cathode Dark Space) 1000 ml/min ƒ w w. Ax» 1000 ml/min v x w w» ƒƒ 300 ml/min, 600 ml/min wš x ww.»» x ew 300 ml/min 20 ma w v x w 40 ml/min ü (Cathode Dark Space) w»ƒ w ƒ. w 600 ml/min œ», x» w He Ar v d Fig. 9 Table 3 ƒƒ y Ar, He v y t w. y w ùkü. ƒ w ù, w y w.», y,, sww w» (Dimethylmethyl-phosphonate(DMMP)) v» w y w z w œ» y yw» z x w»yw Dimethylmethyl-phosphonate (DMMP)ƒ, GC/MS w z» yw y w. Fig. 10» m w» z DMMP Total Ion Chromatogram.» m wš ù z DMMP x.» m w z dimethoxy- propane, dimethyl ester phosphonic acid, ethoxyethyl acetate, butanedinitrile, tirmethyl ester phosphoric acid, trimethyl ester phosphrous acid š bicyclo 2,2,1 hept-2-yl-phosphonic acid ù, mw y w. œ» 13 ml/ Fig. 9. Plasma temperature relate to change of current in each conditions.

8 w šz œ» y yw» p w 21 Table 3. The temperature of He, Ar plasma depend on a current increase current Temperature of He plasma Temperature of Ar plasma (ma) 1st 2nd 3rd RSD(%) 1st 2nd 3rd RSD(%) ( ; Plasma is not to be observed) Fig. 10. GC/MS Chromatogram for dissociation rate of DMMP in D.C. glow discharge. min, 2.5 Torr, ƒw watt (424 V, 60 ma). mw» m w DMMP w. w w y w z w w» ƒ w. ¾ yw»ü v p r. Bx œ» ƒw v ƒ d Bx w. Bx v ƒ Ar He v 4000~4800 K.»yw 500K w, p w yw w 1000 K K w yw wƒ ƒ w, yw wƒ z (99.9% ) GC-MS mw x w (Fig. 10). w x m w yw»

9 22 ½»yÁ yá w». B x xkƒ xk œ» ƒw v w. x w Abnormal j j rv w j œ»» w. j œrv w 50 l y ƒ w x r. 2005w û w w x 1. Chris Lazik and Kenneth Marcus, Spectrochim. Acta. 1993, 48B, S. Caroli, J., Anal. At. Spectrom. 1993, 2, Slevin, P. J.; Harrison, W. W., Appl. Spectrosc. Rev. 1975, 10(2), Akishev, Y. S.; Deriugin, A. S.; Napartovich, I. V.; Trushkin, A. P., N. I. J. Phys. D, Appl. Phys. 1993, 26, Schroeder, S. G.; Horlick, G., Spectrochim Acta Part B, 1994, Masamba, W. R. L.; Ali, A. H.; Winefordner, J. D., Spectrochim Acta B, 1992, 47(4), Kazuaki Wagatsuma and Kiehinosuke Hirokawa, Anal. Chem. 1985, 57, Charles, H.; Corliss and William R. Bozman; Experimental Transition Probabilites for Spectral Line of Seventy Elements. 1962, U.S.A: U.S. Govt. Print. Off. 9. Pillow, M. E., Spectrochim. Acta. 1981, 36B, Howatson, A. M., An Introduction to Gas Discharges. 1976, N.Y: Pergamon Press. 11. Chris Lazik and Kenneth Marcus, Spectrochim. Acta. 1993, 48B, Broekaert, J. A. C.; Brushwyler, K. R.; Hieftje, G., unpublished work.