Kinds of Water Pollution Inorganic Pollutants Organic Pollutants Biologic Pollutants 1
VOCs Volatile Organic Compounds EU 250 101.3 kpa 2
USEPA ( CO, CO 2,, H 2 CO 3 ) (Photochemical Reaction) WHO 50-260 (vapour) (gas) aliphatic hydrocarbons, aromatic hydrocarbons oxygenated hydrocarbons 3
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VOCs,,,,,,,,, 5
VOCs 2 6
1) Non-chlorinated VOCs Non-halogenated hydrocarbons aliphatic hydrocarbons ( fuel oils, gasoline, hexane, idustrial solvents, alcohols, aldehydes, ketone) aromatic hydrocarbons ( - toluene, benzene, ethylbenzene, xylenes, styrene, phenol) VOCs VOCs 144 benzene, toluene, naphthalene propene, 1,3-butadiene, styene alkyl-substituted benzene compounds xylenes, 1-butene/2-methylpropene, propane, 2-methylbutane, ethylbenzene, naphthalene, isopropylbenzene 76.8 % VOCs 7
2) chlorinated VOCs halogenated hydrocarbons chlorinated VOCs (non-chlorinated VOCs) 8
chlorinated VOCs halogenated hydrocarbons Trihalomethanes 9
1 halogenated hydrocarbons 10
halogenated VOCs trichloroethylene (TCE) 30 TCE 11
VOCs 3 1) 2) - 3) (metabolism) VOCs P450 glutathione P450 VOCs CTP2E1 trichloroethylene chloral hydrate CYP2B trichloroethanol trichloroacetic acid; toluene benzyl alcohol benzoic zcid 12
VOCs 1. VOCs VOCs VOCs 2. 2-butanone acetone 13
VOCs 3. VOCs 14
302 ( 40-59 ) Aberdeen, North Carolina Dichloroethylene (DCE) (pesticide dump sites) 4.05 ppb 2.95 ppb (p=0.01) DCE (mitoger-induced lymphoproliferativity) 15
1,1,1-trichloroethane (TRI) 5000 ppm 40 TRI cyclic GMP medulla oblongata 55-58 % cyclic GMP 100 16
VOCs (dichloromethane, n-hexane), plastic compounds (isocyanates polyvinyl chloride) (65%), (53%), (46%), (43%), (1.1-3.5 %) 14,000 Bristol, U.K. (aerosols) VOCs (Xylene, ketones aldehydes) 25%, 19%, 22 % 17
( 2) 2 VOCs (carcinogen) (tumor promoter) ( ) 18
VOCs 3 3 VOCs CNS = Central nervous system 19
VOCs (additive effect) 20
VOCs 8 (EPA) maximun contaminant level (MCL) 21
VOCs oxidizers VOCs VOCs co-meatbolism method anaerobic aerobic oxidation, reduction, dehalogenation VOCs (TCE, PCE, DCM, benzene, toluene) 22
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VOCs VOCs VOCs VOCs 24
There are two methods which are often used for VOCs sampling: sorbent sample tube sampling and air canister sampling. Sorbent Sample Tubes for VOCs sampling The frequently used sorbent sample tubes include charcoal tubes, Tenax tubes and XAD2 tubes. When sampling, the samples are collected by opened tubes connecting to sampling pumps. Airbourne chemicals are trapped onto the surface of the sorbent when the pumps pulling sampled air through the tubes. After sampling, the tubes need to be sealed with push-on caps and freezed during the storage and transportation. 25
Canisters for VOCs sampling VOCs samples are collected into stainless steel canisters which are transported to the laboratory for analysis. Before using, the canisters need to be cleaned and pressurized with nitrogen. The canisters need also to conduct leak checking just before their on-site using. The capacities of canisters include 1L, 2L, 3L, 6L and 15L. For different purposes, the sampling rate should be well controlled. 26
Gas Chromatography (GC) ( 450ºC) 27
GC 2 Gas-Solid Chromatography (GSC) Gas-Liquid Chromatography (GLC) 28
Gas-Solid Chromatography (GSC) stationary phase (adsorption) molecular sieves, porous polymers, silica gel, alumina, activated carbon 29
Gas-Liquid Chromatography (GLC) mobile phase stationary phase partition coefficient 30
Principles of Gas Chromatography Mobile phase mobile phase (carrier) (N 2 ) (He) stationary phase (diffusion) 31
t R t R carrier gas 32
Efficiency of Gas Chromatography GC HETP HETP N carrier gas H optimum velocity 33
Gas Chromatograph 34
Carrier Gas ( ) (Gas tank) High Pressure Steel to 2640 psi Cylinder Designati on Water Capacity (liters) Diameter (inches) Height w/ Valve (inches) Nominal Shipping Weight(lbs)* 049-HP 49-50 9.25 60 150 044-HP 43-44 9.00 56 125 028-HP 27-28 7.00 47 70 016-HP 16-17 7.00 36 53 010-HP 10-11 7.00 28 38 008-HP 7-8 7.00 23 31 *includes estimated weight of contents 35
Regulator 36
Carrier Gas ( ) N 2, He, Ar, H 2 H 2 He N 2 sensitivity 37
carrier gas (detector) detector carrier gas detector carrier gas 2 1. t R 2. detector carrier gas 38
Flow Controller 39
Soap bubble Flow meter 40
Sample Injection System (Injector port) syringe (gas sampling valve) 41
Gas Sampling Valve Load Inject 42
Syringe Micro Syringe Gas Tight Syringe 43
Needle 44
sample chamber carrier gas 45
pyrolysis 46
Column 2 Packed column 1-8. 2-20 oven GSC GLC 47
GSC,,,,, Polarpak Q, Polarpak R t R 48
GLC stationary phase solid support solid support diatomaceous earths (SiO 2 ) solid support 1. 10 2. 1-20 3. 4. 5. 49
stationary liquid phase solid support stationary phase 1. 2. 3. 4. 5. 50
stationary liquid phase liquid phase 5 class Class I (most polar), Class II (polar), Class III (intermediate polarity),, Class IV (low polarity), Class V (non-polar), 51
Open tubular column (capillary column) (0.3-0.6 mm) (25-100 m) packed column packed column 100 52
Oven Isothermal Temperature programmed 53
Detector reproducibility detector 2 1. detector 2. detector 54
detector 1 1. Nitrometer CO 2 carrier gas CO 2 CO 2 KOH 2. Automatic Recording Buret 3. Infrared Analyzer 4. Mass Spectrometer 55
detector 2 1. Hydrogen Flame Detector (HFD) 2. Flame Ionization Detector (FID) 3. Thermal Conductivity Detector (TCD) 4. Flame Photometric Detector (FPD) 5. Electron Capture Detector (ECD) 6. Detector nitrogen-phosphorus detector (NPD) 56
Thermal Conductivity Detector (TCD; Universal) detector (filament) carrier gas bridge bridge 57
Flame Ionization Detector (FID; Selective) carrier gas flame jet FID 58
Electron Capture Detector (ECD; Selective) ECD detector (high electronegativity) 59
ECD (radioactive source) (beta radiation) Ni 63 carrier gas N 2 5% CH 4 Ar 60
Nitrogen Phosphorus Detector (NPD; Selective) FID 61
Flame Photometric Detector (NPD; Selective) detector (chemiluminescence) filter photomultiplier tube 62
detector detector detector 1. 2. (high sensitivity) 3. 4. High reproducibility 5. carrier gas carrier gas 6. 7. dynamic range 8. (selectivity) 63
(Qualitative analysis) retention time identify peak spiking (Quantitative analysis) (recorder) integrator 64
1. RT (Ethanol, Iso-propanol, Tertbutanol) 2. calibration curve 0.5, 1.0, 1.5, 2.0% 3. 4. 65
GC Column : Rt-QPLOT, 30 m, 0.32 mm ID, 10 μm Col. temp. : program from 100 to 240C @ 5 C/min Inj. : 1.0 μl split (70:1) @ 250C Carrier gas : He @ 1.1 ml/min Detector : FID @ 270C 66