Detector gas Injector Purge flow DetectorFID ECD Carrier

가스 크로마토그래피 Detector gas Injector Purge flow Detector(FID, ECD…. ) Carrier Gas (운반가스) Split Signal output to Data system 분석컬럼 Gas Oven 3

MSDS의 중요성 a) 유기화합물 분석에서 고농도시 겹칠 수 있는 성분 : 예) Ultra-1 column 사용 ① Methyl acetate & Dichloromethane ② Ethyl acetate & n-Hexane ③ 1 -Butanol & Iso-Propyl acetate & Benzene ④ n-Buthyl acetate & Tetrachloroethylene(PCE) ⑤ m-Xylene & p-Xylene ⑥ c-Hexanone & Iso-Pentyl acetate ⑦ o-Xylene & 1, 1, 2, 2 -Tetrachloroethane b) 단위 공정의 MSDS 확인 c) Column의 선택(비극성, 중성, 극성) d) Bulk sample의 GC/MS 확인 e) 유기화합물의 경우 분석의뢰지에 MSDS 또는 전회 측정에서 나타난 물질의 체크 (단일, 복합) 실제 분석자료와 단위공정에서 사용물질의 종류, 사용량 및 특성 등의 인지문제 6

오븐 온도에 따른 분리능 • Inadequate resolution at 95˚C • Improved resolution at 74˚C • Baseline resolution at 45˚C Note: MCHx changes elution order (3 rd peak to the 1 st peak) due to solubility differences DMHx = Dimethylhexane MCHx = Methylcyclohexane 7

피리딘(Pyridine) 분석방법 1. 측정 및 분석방법 개요 a) 노출기준 한국: 5 ppm, 미국(TLV): 1 ppm b) Sampling Sampler : Solid Sorbent Tube (활성탄; 100㎎/50㎎) Flow rate : 0. 01 - 1 L/min Volume : 18 L - 150 L Sample No. : 3개/사업장 × 10 사업장 = 30개 9

피리딘(Pyridine) 분석방법 1. 측정 및 분석방법 개요 c) Measurement Technique : Gas Chromatography, FID Method No. : NIOSH 1613 Desorption : 1 m. L Methylene chloride, 30 min Temperature : Injection - 260℃, Detection - 285℃, Column - 140℃ Injection Volume : 5㎕ Column : Capillary column (30 m× 0. 32 mm, 1㎛ DB-5) d) Reagents ① Methylene chloride (CH 2 Cl 2) : 특급, Chromatographic quality ② Pyridine : 특급, Reagent grade ③ Hexane : Chromatographic quality ④ DE stock solution, 300 mg/m. L : Weigh 3 g Pyridine (ca. 3. 1 m. L) into a 10 m. L volumetric flask. Dilute to volume with Hexane. Prepare in duplicate. ⑤ Nitrogen, purified. ⑥ Hydrogen, purified ⑦ Air, filtered, compressed. 10

피리딘(Pyridine) 분석방법 2. 분석조건 근거 : NIOSH 1613 분석법 Variables Conditions Instrument HP 6890 (U. S. A. ) Detector FID Injection volume 1. 0㎕ Column HP-5 (30 m× 320㎛× 0. 25㎛) Carrier gas He Gas flow rate Air 450㎖/min H 2 40㎖/min He makeup flow 45㎖/min Constant column flow 1. 0㎖/min Split ratio 50. 0 : 1 Temperature Injector 280℃ Detector 280℃ Oven temperature programing 1 st Temp. 40℃ Hold time 2 min Rate 1 20℃/min 2 nd Temp. 60℃ Hold time 0 min Rate 2 40℃/min 3 nd Temp. 180℃ Hold time 2 min Post run temp. 240℃ Hold time 1 min 11

피리딘(Pyridine) 분석방법 3. 시약제조 Main desorption solvent Codesorption solvent Internal standard solution Standard solution Dichloromethane (Merck, Germany) Methanol (Merck, Germany) n-Hexane (Merck, Germany) Pyridine (Merck, Germany) Molecular weight (g/mol) 84. 93 32. 04 86. 17 79. 1 Specific gravity (kg/L) 1. 33 0. 79 0. 66 0. 98 Purity (%) 99. 9% 98. 5% 99. 5% TLV (ppm) 50 200 50 5 Volume (L) 10 10 Volume weighted TLV (mg) 1. 73681 2. 62086 1. 76217 0. 16176 SG × Purity 1. 32867 0. 78921 0. 65010 0. 97510 90㎖ 10㎖ 300㎕ Contents Mixing volume of desorption solvents Dilution ratio of Stock solution 19 1 12

피리딘(Pyridine) 분석방법 4. 검량 및 spike 시료의 제조 Stock solution(㎕) /㎖) Concentration (mg) Peak area Blank / 1㎖ 0. 00000 1㎕ / 1㎖ 0. 04876 3. 55029 2㎕ / 1㎖ 0. 09751 10. 06408 4㎕ / 1㎖ 0. 19502 23. 16000 8㎕ / 1㎖ 0. 39004 49. 11259 Equation Y = 133. 5109 X - 2. 9382 (r=0. 999998) Sample number Spike volume (pyridine stock solution) Spiked amount (㎎/sample) 1 2 ㎕/sample* 0. 09751 2 4 ㎕/sample 0. 19502 3 6 ㎕/sample 0. 29253 *sample : charcoal tube 13

피리딘(Pyridine) 분석방법 4. 검량 및 spike 시료의 제조 Calibration curve of pyridine standard solution with 10% Me. OH in DCM 14

피리딘(Pyridine) 분석방법 5. LOD와 LOQ LOD and LOQ of pyridine analysis with 10% Me. OH in DCM 측정횟수 농도(mg) Peak area 1 0. 1950 26. 0683 2 0. 1950 25. 9879 3 0. 1950 25. 8920 4 0. 1950 25. 9036 Mean ± SE Standard calibration curve 25. 9630 ± 0. 0411 Y = 133. 5122 X - 2. 9386 (r = 0. 999998) LOD*(ppm, 10 L 기준) 0. 00092㎎ (0. 0283 ppm) LOQ**(ppm, 10 L 기준) 0. 00305㎎ (0. 0934 ppm) * LOD = 3 SE/b (SE: standard error, b: slope, NIOSH, 1995) **LOQ = 3. 3 LOD 15

피리딘(Pyridine) 분석방법 6. 탈착효율 Desorption efficiency of pyridine by type of solvents Desorption solvents Internal standard No. Desorption efficiency (Mean ± SD, %) Only DCM* n-Hexane 1 st 51. 66 ± 1. 33 5% Me. OH in DCM n-Hexane 1 st 67. 36 ± 1. 49 1 st 81. 62 ± 0. 92 2 nd 86. 18 ± 1. 08 Mean 83. 90 10% Me. OH in DCM *DCM n-Hexane : Dichloromethane 16