w y wz 8«( 4y) 00~00, 2005 J. of the Korean Society for Environmental Analysis CWPO œ w 1,4- s Á Á * û y, * w yœ lœw 1,4-Dioxane Treatment using Catalytic Wet Peroxide Oxidation Process Jong-min Kang, In-cheol Cho, and Ju-yeong Song* Gyeongsangnam-do Provincial Government Institude Public Health & Environment *Department of Chemical Engineering, Changwon National University 1,4-dioxane, a possible carcinogen, has been found in the Nakdong river and became a social issue. Synthetic and industrial wastewater containing 1,4-dioxane were treated by catalytic wet peroxide oxidation (CWPO) process. Complete decomposition for synthetic wastewater containing 500 mg/l of 1,4-dioxane was obtained in 10 minutes when 1.0 g/l of copper powder and 196 mm of hydrogen peroxide was applied at 100 o C and ph 3. Similarly, an industrial wastewater containing 780 mg/l of 1,4-dioxane was completely decomposed within 30 minutes when 1.5 g/l of copper and 588 mm of hydrogen peroxide was applied, while COD Cr was reduced by 60 %. Factors that affecting the experiment were ph, temperature, amount of hydrogen peroxide, and the forms and amount of the catalyst. Ethylene glycol diformate, various forms of organic acids and aldehydes, were produced as by-products of decomposition. Reaction rate was proportionally increased with the dose amount of catalyst. Treatment efficiency was also proportionally increased with the dose amount of hydrogen peroxide. The 1,4-Dioxane decomposition rate of industrial wastes showed the first order reaction with 2.5 10 3 s 1 of rate constant. Key words : 1,4-Dioxane, CWPO, catalytic wet peroxide oxidation, Cu catalyst 1. Ÿ w 1,4- (C 4 H 8 O 2 ) WHO w» (International Agency for Research on Cancer, IARC) w,» û ƒ» w w ƒ Group 2B wš 1). y (U.S. EPA) 2000 y w» w «še tw 1,4- ƒ 0.3 mg/l 10,000 1 Õ x š x 2). wr, y w 2000~2002 ¾ 35 w w k w 1,4- ù k ƒ ùkù y y w 2004 9 ù w 1,4- ƒ 50 µg/l w z š. l»ƒ y e š w»yw 1,4- w w ƒ» y k ù œ» k» z. š w w w w œ y ƒ, š y œ (Advanced Oxidation Proccess, AOP) UV/ H 2 O 2» n ƒ w» s, k Ÿ y w w z To whom correspondence should be addressed.
2 Á Á ƒ. y(catalytic Wet Oxidation, CWO) œ 1970 Sanada Katzer3) w s z x 200 y œ ù w» s š» y w w yw w w z y w.» y œ (œ») y y w w w e x j œ CWPO(catalytic wet peroxide oxidation) œ w. CWPO œ w 1,4- w e y ph,, xkƒ 1,4- w e w w š w wš w s w ƒ mw. 2. 2.1. x 1,4- (C 4 H 8 O 2 ; 99%, Junsei Chemical Co., Ltd., extra pure) y (H2O2; 30%, DC Chemical Co., Ltd., extra pure), (150~300 mesh; 99.85%, Samchun pure Chemical Co., Ltd., extra pure) q(samchun pure Chemical Co., Ltd.), ( ), (CuSO 4 5H 2 O; Kanto Chemical Co., Inc, extra pure) w w š ph w y (H 2 SO 4 ; 95%, DC Chemical Co., Ltd., extra pure) ƒ (NaOH; 99.5%, Samchun pure Chemical Co., Ltd., extra pure) w 1 N, 0.05 N H 2 SO 4 1 N, 0.05 N NaOH ƒƒ w w. w» w ethylene glycol diformate(c4h6o4; Merck, guaranted reagent) w formaldehyde(ch 2 O; Supelco, 100 µg/ml) acetaldehyde(c 2 H 3 O; Supelco, 100 µg/ml) t t w.» d methoxyacetic acid (C 6 H 8 O 3 ; Acros Organics), (HCOOH; 98%, Junsei Chemical Co., Ltd., guaranted ragent), (CH 3 COOH; 99%, Junsei Chemical Co., Ltd., Table 1. Characteristics of synthetic wasterwater 1,4-Dioxane ph COD Mn COD Cr 500 6.5~6.7 25 890 guaranted reagent), propionic acid(ch 3 CH 2 COOH; 100%, Junsei Chemical Co., Ltd., guaranted reagent), butyric acid (CH 3 CH 2 CH 2 COOH; 99%, Junsei Chemical Co., Ltd., guaranted reagent), glycolic acid (HOCH 2 COOH; 70% in water, Kanto Chemical Co., Ltd.), oxalic acid((cooh) 2 Á2H 2 O; 99.5~100.2%, DAEJUNG( ), extra pure grade reagent) w. x œs p Table 1 ù kü. 2.2. e x y e Fig. 1 ùkü. œs 1,4- w 500 mg/l š k x w w s w.» j» 1,000 ml» agitator ew y yw 200~250 rpm w, š» w þƒ ew. ƒ»ƒ ƒ q w 100 o C x ew. 1,4- w x Fig. 1. Experimental apparatus of catalytic wet peroxide oxidation at atmospheric pressure.
CWPO œ w 1,4- s 3 Table 2. GC/MSD operating conditions for 1,4-dioxane Column : HP-5MS (25 m 0.25 mm I.D 0.25 µm, film thickness) Carrier gas flow : He(>99.9999%) at 1.3 ml/min Splitless injection Injection temp : 200 o C Transferline temp : 280 o C Oven temp. program : initial initial rate final final temp( o C) time(min) ( o C/min) temp( o C) time(min) 30 7 20 90 0 260 2 SIM mode(solvent delay : 3.50 min) Group Start time(min) Selected lons, m/z 1 4.00 (88,58,43) 2 7.00 (77,79,41) w MSD(Agilent Technologies, 5973N)ƒ GC(Agilent Technologies, 6890N) w Table 2. w y w» w TOC(SHIMADZU, TOC-V CSM ) wì COD Mn COD Cr œ x w xw ƒ ph ph analyzer(orion, 920A) w d w. w y w» w ethylene glycol diformate(egdf) 10 ml w 100 ml š yùp 0.5 g z t- butyl methyl ether w GC/FID(Agilent Technologies, 6890N) w.» UV-Vis detector(waters, 996)ƒ High-performance liquid chromatography(hplc, Waters, 2690) w IC-Pak TM Ion- Exclusion(7.8 150 mm) e ü 1.0 ml/min w 215 nm UVq d w w dinitrophenylhydrazine(dnph) yw z UV- Vis detector(waters, 996)ƒ High-performance liquid chromatography(hplc, Waters, 2690) w ZORBAX Eclipse XDB-18(4.6 250 mm) e ü 1.5 ml/min w 360 nm UVq d w. 3. š 3.1. w œs 1,4- w 3.1.1. y w CWPO œ, y w ³ w» w y ƒƒ g yww w z w Fig. 2 1,4- s 80 C ƒw o y ù. n w ù y w 80 25% 1,4- w. w y ƒ n 80 100% w. 1,4- (500 mg/l, 1 L) 80 C o 2.0 g š jš y w y j z w Fig. 3 y ƒw 1,4- w ƒw. y 196 mm 80 1,4- w 392 mm 50, 784 mm 40 w. ù y ƒ k s y w 1,4- w ƒ z ùkù 196 mm š jš x ww. 3.1.2. xk z n w» w 1,4- (500 mg/l, 1 L) 80 o C, ph 3 y 196 mm š jš Fig. 2. Degradation of 1,4-dioxane by oxidizing agents and catalyst in CWPO process (80 o C, ph 7).
4 Á Á Fig. 3. Effects of hydrogen peroxide dosage on 1,4- dioxane degradation (80 o C, ph 7, Cu powder 20 g/ L). y j xw, Fig. 4 ù kü.» ƒw 1,4- w ƒ ƒw ƒ 1.0 g z ùküš, n z w. ü y w ƒ, CWPO œ OH e 1,4- w w, ƒ OH e ww w w». w CWPO œ s» w k w š j ù w k z w v w e w. 1,4- w x y w» w xk q, w w z w (Fig. 5). 1,4- (500 mg/l, 1 L) 80 o C, ph 3 y 196 mm š jš 1.0 g q ƒƒ 30.0 g» n w. q xk n w, 1.0 g n w z ùkþ, xk q xk w 1,4- z, q w t j» q. 3.1.3. ph y z phƒ z e w w» w» ph 3, 7, 11 š jš x w. x Fig. 6 ùkü ph 3 30 100% w ph 11 25%ƒ w. ph 3 w y ƒ ƒ ww OH e ƒ wš y w w š. Meeker y ƒ 4) ph 2.0~4.0 ƒ w 2.0 ù 4.0 y w ƒ ƒw š w. ph 11 10 z ù w Buxton w e y 5) Fig. 4. Effects of catalyst dosage on CWPO 1,4-dioxane degradation (80 o C, ph 3, Cu powder 1.0 g/l, H 2 O 2 196 mm). Fig. 5. Effects of various type of copper catalysts on CWPO 1,4-dioxane degradation (80 o C, ph 3, H 2 O 2 196 mm).
CWPO œ w 1,4- s 5 Fig. 6. Effects of ph on CWPO 1,4-dioxane degradation (80 o C, Cu powder 1.0 g/l, H2O2 196 mm). ƒ ƒ ww OH e w OH e O e y OH e k š w. CWPO œ ƒ 1,4- z ƒw (Fig. 7). w 1,4- w ƒ ƒw. 3.2. w»»y 1,4- w w ƒ w, Hill 6) TiO 2 w photocatalytic degradation ethylene glycol diformate y w š, formic acid, acetic acid, glycolic acid, formaldehyde, acetaldehyde w. Michael 4 q 7) q (205, 358, 618, 1071 khz) w 1,4- w e w ethylene glycol diformate, methoxyacetic acid, formic acid, glycolic acid, formaldehyde xþ. Maurino 8) TiO 2 / UV, H 2 O 2 /UV w ethylene glycol diformate formic acid, formaldehyde, oxalic acid y w. ww 1,4- t ethylene glycol diformateƒ w» w y yk w. GC/FID HPLC w w d w ethylene glycol diformate w formic acid, oxalic acid» formaldehyde, acetaldehyde w ƒ w y (Fig. 8). 1,4- w y w» w 1,4- (500 mg/l, 1 L) 80 o C, y 196 mm, ph 3 1.0 g w w. Fig. 9 1,4-30 wƒ TOC 1,4- w w w ƒ 30~40»y 40% w z w w. y ƒ Fig. 7. Effects of reaction temperature on CWPO 1,4- dioxane degradation (ph 3, Cu powder 1.0 g/l, H 2 O 2 196 mm). Fig. 8. Reaction intermediates during the 1,4-dioxane treatment using CWPO process (80 o C, ph 3, Cu powder 1.0 g/l, H 2 O 2 196 mm).
6 Á Á Fig. 9. Removal of TOC and 1,4-dioxane using CWPO process (80 o C, ph 3, Cu powder 1.0 g/l, H 2 O 2 196 mm). OH e w w» w»y j w. 40 y d w 0.14 mg/l y û. 3.5. CWPO œ w s 3.5.1 s x ù š 1,4- s k y ü w w ƒ w s l wœ š s w ƒ z š. s l wœ s 1,4- ƒ š A s w 1,4- w x ww. s Table 3. œs w x y, 80 o C, ph 3, 1.0 g/l, y 20 ml/l s z Fig. 15 ùkü. 1,4- œs 30 100% ù s z 40. s w ehylene glycol, telephathalic acid» w q, œs s 1,4- ƒƒ 500 mg/l 780 mg/l ƒ 1 : 1.6 w CODCr Table 2 3 16 ù ƒ. y y ƒ 1,4- w s w y ƒ w» w z û q. š z s 1,4- w x x s ƒ¾ 100 C š o w xw. 3.5.2. xk CWPO œ x 1,4- s x w», w g w. w ƒ w ³ w. q ph 3, 100 C y o 588 mm w s w z Fig. 11 ùkü. (Cu : 500 mg/l) w» l 1,4- w w û w q(10.0 g/l) n w» w w ƒ w w û. Table 3. Characteristics of industrial wastewater used in the experiment 1,4-dioxane ph SS COD Mn COD Cr 780 3.65 0.6 7,740 14,860 Fig. 10. Degradation of 1,4-dioxane using CWPO process on the industrial wastes (80 o C, ph 3, Cu powder 1.0 g/l, H 2 O 2 196 mm).
CWPO œ w 1,4- s 7 Fig. 11. Effects of various catalysts (Cu plate : 10.0 g/l, Cu solution: 500 mg/l) on CWPO 1,4-dioxane degradation of the industrial wastewater (100 o C, ph 3, H 2 O 2 588 mm) Fig. 12. Effects of hydrogen peroxide dosage on CWPO 1,4-dioxane degradation of the industrial wastes (100 o C, ph 3, Cu 1,500 mg/l). ƒ ³ w š w. q(10.0 g/l) (Cu : 500 mg/l) n w q(10.0 g/l), (Cu : 500 mg/l) g ƒ w q ƒ y ƒ ƒw». w 1,4- x w ph, s š w ( q, ) z š. 3.5.3. 1,4- z e CWPO œ s w e w» w 100 o C, (Cu: 1,500 mg/l), ph 3 y y j xw (Fig. 12). y 196 mm 1,4-20 59%, 392 mm 30 90%, z 1,4- wƒ ù. y 588 mm 1,4-30, 686 mm w 100%. w, y 588 mm COD Cr 6,040 mg/l 60% wš, Fig. 13. Effects of copper catalyst dosage on CWPO 1,4- dioxane degradation of the industrial wastes (100 o C, ph 3, H 2 O 2 588 mm). 686 mm CODCr 4,590 mg/l 70%. Fig. 17 y 1,4- z CODCr ƒw. y ƒw 1,4- z ƒw w. s 1,4- w w wù» w w 200 mg/l, 500 mg/ L, 1,000 mg/l, 1,500 mg/l, 2,000 mg/l w xw (Fig. 13). 200 mg/l w w 1,4- w 80 95%ƒ š z w š. 500mg/L w 80 1,4-
8 Á Á Fig. 14. Rate constant of CWPO 1,4-dioxane degradation of the industrial waste (100 o C, ph 3, H2O2 588 mm). w. 1,000 mg/l, 1,500 mg/l, 2,000 mg/l w 40 w óû, 1,500 mg/l 2,000 mg/l w ƒ 1,500 mg/l w ƒ š q. s 1,4- w 1,4-. s 1,4- w» w (1,500 mg/l) w 1 2.5 10-3s-1 ùkü (Fig. 14). z ph y 1,4- w ph 2.3 š,»y š» k 1,4- w wš. 4. 1,4- œs s w CWPO œ w xw. 1. œs (1,4- : 500 mg/l) 100 C o, ph 3 1.0 g/l y 196 mm w 10 ü 1,4-100% w. 2. s (1,4- : 780 mg/l) 100 o C, ph 3 (Cu : 1,500 mg/l) y 588 mm w 30 ü 1,4-100% w š COD Cr 60% w. 3. x w ph,, y, xk w ethylene glycol diformate ƒ» w ƒ. 4. CWPO œ w 1,4- n w ƒw š, z y y w w. 5. xk ( q, ) xk w ù, ƒ ³ w» xkƒ w, s 1,4- w 1 2.5 10 3 s 1. š x 1. National Cancer Institute. Carcinogenesis technical report series No. 80. Bioassay of 1,4-Dioxane for Possible Carcinogenicity(CAS No. 123-91-1). DHEW (NIH) Publication No. 78-1330. Bethesda, MD: National Institues of Health, 1978. 2. U. S. EPA. Drinking Water Standard and Health Advisories. Washington, DC: Office of Water, United States Environmental Protection Agency, 2000. 3. Sadana, A. and J. R. Katzer, Ind. Eng. Chem. Fundam., 1974, 13, 127. 4. Meeker, R. E., Stabilization of Hydrogen Peroxide, US Pat. 3, 1965, 208, 606. 5. Buxton, G. V., C. L. Greenstok, W. P. Helman and A. B. Ross, J. Phys. Chem. Ref. Data., 1988, 17, 513-531. 6. Hill, R. R., G. E. Jeffs and D. R. Roberts, J. Photochem. Photobiol. A : Chem., 1997, 108, 55-58. 5. Michael, A., Beckett and Inesz Hua, Environ. Sci. Technol., 2000, 34, 3944-3953. 6. Maurino, V., P. Calza, C. Minero, E. Pelizzetti and M. Vincenti, Chemosphere, 1997, 35, 2675-2688.