空氣中臭味還原性硫化物線上濃縮與分析On-line enrichment and analysis of

reduced sulfur compounds in the atmosphere

報告者 : 林岱縈指導老師 : 王家麟 教授

1

Reduced sulfur compoundsH2S/ COS/ CH3SH/ C2H5SH/ CS2/ CH3SCH3/ CH3SSCH3

(DMS) (DMDS)

CCN

aerosol

RSCs SO42-

Oxidation RegionalTemperature

2

S

SourceNatural emission

Anthropogenic emission

3

Ocean Volcano

Factory Wastewater treatment

DMS H2S, SO2

H2S, CH3SH, DMS, CS2…. H2S, SO2, C2H5SH, DMS, DEDS….

R SC

Preconcentration methods

Sorption on metal surface Solid sorbents

Cryogenic trapping

Au

S SMolecular sieve 5A/ Tenax TA

Ambient concentration levels (ppbv)

H2S SO2 DMS CS2 COS

~0.2 ~0.1 ~0.001 ~0.02 ~0.5

Anal. Chem. 1978, 50, 992-996/ Analytica Chimica Acta,1995, 306, 259-266 / USEPA, Method 15/ Atmospheric Science for Environmental Scientists4

易沾黏、反應性高 Loss 背景濃度低

Detection limit

H2S other RSCs

LN2

The research goal

Molecular sieve 5A/ Tenax (USEPA, Method 15)

電子降溫至 -20°CFind a better sorbent

5

Solid sorbent Cryogenic trap

Experimental setup

GC/ PFPD

N2Sample

GC He

MFC pump

N2Sample

GC He

MFC pump

-20°C HeatCool

Sampling Injection

Principle of PFPD

77

S2* hʋ

1Filling

2Ignition

3Propagation

4Combustion

5Extinction

Wall gasH2/ zero air

Combustor gasH2/ zero air

2200°C

點火室

燃燒室

Time-delay燃燒室時劑圖

Calibration system

MFC I

MFC III

vent

混合室

MFC II

烘箱 30°C

水冷機1°C

C2H5SHDMS DMDS

CS2

Zero air

( 可調控以改變稀釋倍率 )4 L/min

50 mL/min( 固定 )

1 mL/min( 固定 )

H2S

滲透管實圖

8

滲透管

滲透管

Stability test of permeation tube

9

50 70 90 110 130 150 170 190 210 230 250 0E+00

1E+03

2E+03

3E+03

f(x) = 18.0628888888889 x − 604.966666666666R² = 0.996107483809952

C2H5SH

Volumn ( mL )

Res

pons

e

50 70 90 110 130 150 170 190 210 230 250 0E+00

5E+03

1E+04

2E+04

f(x) = 55.7483333333333 x − 182.753333333329R² = 0.998838652748502

DMS

Volumn ( mL )

Res

pons

e

50 70 90 110 130 150 170 190 210 230 250 0

100200300400500600700800900

f(x) = 4.27711111111111 x − 27.6733333333335R² = 0.998770193775762

DMDS

Volumn ( mL )

Res

pons

e

20 40 60 80 100 120 140 160 180 2000E+00

5E+03

1E+04

f(x) = 86.4466666666667 x − 665.400000000001R² = 0.998550999298153

CS2

Volumn ( mL )

Res

pons

e

N=3

N=3

N=3

N=3

Tenax TA

Stability test of permeation tube

10

0.006 0.008 0.01 0.012 0.014 0.016 0.018 0.02 0.022 0.0240E+00

1E+03

2E+03

3E+03

f(x) = 116302.142775251 x − 348.348902735718R² = 0.997470683628443

C2H5SH

Dilution rate

Res

pons

e

0.006 0.008 0.01 0.012 0.014 0.016 0.018 0.02 0.022 0.0240E+001E+032E+033E+034E+035E+036E+037E+038E+039E+03

f(x) = 340982.672080516 x + 105.048732697243R² = 0.999314823320347

DMS

Dilution rate

Res

pons

e

0.006 0.008 0.01 0.012 0.014 0.016 0.018 0.02 0.022 0.0240

100

200

300

400

500

600

700

f(x) = 24078.5071768864 x + 31.7536354170812R² = 0.99657429967726

DMDS

Dilution rate

Res

pons

e

-3E+03

2E+03

7E+03

1E+04

R² = 0

CS2

Dilution rate

Res

pons

e

N=3

N=3

N=3

N=3

Tenax TA

滲透管已可作為標準氣體使用，改變稀釋比例並不影響滲透管穩定輸出的能力

Results and discussion

Desorption temperature

1. Light RSC (H2S)

Micro (<2 nm)Meso (2-50 nm)Macro ( >50 nm)Non

Look for the best material tocompare with Molecular sieve 5A

Look for the best material tocompare with Tenax TA

2. Heavy RSCs (C2H5SH/ DMS/ CS2/ DMDS)

Desorption temperature Meso (2-50 nm)Macro ( >50 nm)

Trapping T.StabilityCalibration

Trapping T.StabilityCalibration

11

ChallengeVolatile

ReactivityH2O

12

Micro-pore < 20Å

MS-5A MS-13X silica gel Carboxen1000

Carboxen 1003

Carbosieve SIII

5 Å 10 Å 20 Å 10-12 Å 5-8 Å 4-11 Å

Ca2+ 沸石 Na+ 沸石 SiO2 CMS CMS CMS

Meso-pore 20-500ÅUnibeads

1SUnibeads

2S MCM-41 MCM-48 Carboxen1016

Carbopack X

PorapakQ

Haysep D

22 Å 60 Å 29 Å 37 Å N/A 100 Å 75 Å 330 ÅSiO2 SiO2 MCM MCM CMS GCB VB/DVB DVB

Macro-pore >500 Å

Tenax TA2000 Å

polymer

Non-poreAu-glass beads glass beads

-- --

Au/SiO2 SiO2

Micro-meso Micro-macroNCL-A9K4 Glass sand

5-300 Å 30-2500 Å

Charcoal SiO2

5A

13X

Silica gel

NCL-A9K4

MCM48

MCM-41

Carbopack X

Porapak Q

Glass beads

Gold

Unibeads 2S

Unibeads 1S

Temperature

Res

pons

e

H

H

LL

1. Light RSC (H2S)Unibeads 1S

13

SiO2 VS carbon in H2S

14

Carboxen 1003

Carboxen 1000

Carbosieve X

0 50 100 150 200 250 300 3500

200400600800

10001200140016001800

Silica gel

Temperature ( °C )

Res

pons

e

Micro

Meso

40 60 80 100 120 140 160 180 2000E+00

1E+04

2E+04

3E+04Unibeads 1S/ 2S

Unibeads 1SUnibeads 2S

Temperature ( °C )

Res

pons

e

0 50 100 150 200 250 3000E+00

1E+03

2E+03

3E+03

4E+03

5E+03Carbopack X

Temperature ( °C )

Res

pons

e

推測碳材比 SiO2 對 H2S 有較強作用力，因此脫附效率不佳 !

Carboxen 1016

0 50 100 150 200 250 300 3500E+00

1E+04

2E+04

3E+04 Unibeads 1S/ Glass sand vs MS-5A

5A

Unibeads 1S

Temperature ( °C )

Res

pons

e

0 50 100 150 200 250 300 3500E+00

1E+03

2E+03

3E+03

4E+03H2S in Non-porous

Glass beads

Gold

Temperature ( °C )

Res

pons

e

Desorption temperature

0 50 100 150 200 250 300 3500E+00

1E+03

2E+03

3E+03H2S in Micro-pore

5A

13X

Silica gel

NCL-A9K4

Temperature ( °C )

Res

pons

e

0 50 100 150 200 250 300 3500E+00

1E+04

2E+04

3E+04H2S in Meso-pore

Unibeads 1S

Unibeads 2S

MCM48

MCM-41

Porapak Q

Carbopack X

Temperature ( °C )

Res

pons

e

0 2 4 6 8 10 12 14 0E+00

1E+03

2E+03

3E+03

4E+03

5E+03

6E+03

7E+03

8E+03

9E+03

1E+04

f(x) = 3483.55852786515 x + 303.763945578226R² = 0.998681072900552

f(x) = 92.980095556474 x + 96.9702878663387R² = 0.998191310122337

Calibration

5ALinear (5A)Unibeads 1S

ng

Res

pons

e

-30 -20 -10 0 10 20 30 400E+00

1E+03

2E+03

3E+03

4E+03

5E+03

6E+03

7E+03

8E+03

9E+03Trapping Temperature

Unibeads

MS-5A

。 C

Res

pons

eTrapping temperature/ Calibration

(Unibeads 1S vs. MS-5A)

N=3

1616

5.12ppb

Stability %RSD (N=10)

Unibeads 1S MS-5A

1.78 % 2.78 %

H2O

約 70 次實驗後， Glass sand 氣通量不足

12.4ppb

0.5-25 ppbv H2S Chromatogram

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10E+001E-012E-013E-014E-015E-016E-017E-018E-019E-011E+00

f(x) = NaN x + NaNR² = 0 Unibeads 1S

ppbvR

espo

nse

N=3

0.5 ppbv

25 ppbv

LOQ (10σ) for H2S: 0.17 ppbvLOD (3 σ) for H2S: 0.13 ppbv

17

18

Meso-pore 20-500ÅUnibeads

1SUnibeads

2S MCM-41 MCM-48 Carbopack X

PorapakQ

Haysep D

22 Å 60 Å 29 Å 37 Å 100 Å 75 Å 330 ÅSiO2 SiO2 MCM MCM GCB VB/DVB DVB

Macro-pore >500 Å

Tenax TA

2000 Å

polymer

Non-poreAu-glass beads glass beads

Non Non

Au/SiO2 SiO2

2. Heavy RSCs (C2H5SH/ CS2/ DMS/ DMDS)

0 50 100 150 200 250 300 3500E+00

1E+04

2E+04

3E+04Meso-pore in H2S

Unibeads 1S

Unibeads 2S

Porapak Q

Carbopack X

Temperature ( °C )

Res

pons

e

19

The chosen material for heavy RSCs

Meso-pore 20-500ÅUnibeads

1SUnibeads

2SPorapak

QHaysep

D22 Å 60 Å 75 Å 330 ÅSiO2 SiO2 VB/DVB DVB

Macro-pore >500 Å

Tenax TA

2000 Å

polymer

Desorption temperature of C2H5SH / CS2 / DMS / DMDS

Compared with Tenax TA

Desorption Temperature

0 50 100 150 200 250 300 3500E+00

1E+03

2E+03

3E+03

4E+03

5E+03

6E+03

7E+03

8E+03

9E+03 DMS

Temperature ( °C )

Res

pons

e

0 50 100 150 200 250 300 3500.0E+00

1.0E+03

2.0E+03

3.0E+03

4.0E+03

5.0E+03

6.0E+03

7.0E+03

8.0E+03

9.0E+03CS2

Temperature ( °C )

Res

pons

e

0 50 100 150 200 250 300 3500

100

200

300

400

500

600

700 DMDS

Temperature ( °C )

Res

pons

e

0 50 100 150 200 250 300 3500.0E+00

2.0E+02

4.0E+02

6.0E+02

8.0E+02

1.0E+03

1.2E+03

1.4E+03C2H5SH

Temperature ( °C )

Res

pons

e

N=3

N=3

N=3

N=3

20

150°C 150°C

150°C150°C

Byproduct: C2H5SSC2H5 (DEDS)

2C2H5SH→ C2H5SSC2H5 + H2

DEDSDEDS

Tenax TAUnibeads 1S

at 150°C

0 50 100 150 200 250 300 3500

200

400

600

800

1000

1200

1400

1600DEDS

Temperature ( °C )

Res

pons

e

0 50 100 150 200 250 300 3500

200

400

600

800

1000

1200

1400C2H5SH

Unibeads1STenax TAUnibeads2SPorapakQHaysep D

Temperature ( °C )

Res

pons

e

Tested Material (peak area at 150°C)

Tenax TA (peak area at 150°C)Normalization =

Ranking

Desorption at 150°C

Unibeads 1S compared with Tenax TA in C2H5SH/ DMS/ CS2/ DMDS22

0

0.5

1

1.5

2

2.5

3C2H5SH

DMS

DMDS

CS2

Nor

mal

izat

ion

Unibeads 1S Unibeads 2S Porapak Q Haysep DTenax TA

DMS

CS2

-30 -20 -10 0 10 20 30 400E+00

1E+04

Tenax TA

C2H5SH

DMS

DMDS

CS2

Temperature( °C )

Res

pons

e

N=3

-30 -20 -10 0 10 20 30 400E+00

5E+03

1E+04

2E+04 Unibeads 1S

Temperature ( °C )

Res

pons

e

N=3

%RSD (N=10) C2H5SH DMS CS2 DMDS

Unibeads 1S 0.8% 0.82% 2.07% 1.76%

Teanx TA 2.56% 1.65% 1.11% 3.24%

( -20 °C )

Trapping temperature

Stability

23

Trapping Temperature (Unibeads 1S vs. Tenax TA)

Calibration

40 60 80 100 120 140 160 180 2000

100

200

300

400

500

600

700

800

f(x) = 3.538126 x + 58.9190399999998R² = 0.996544000799983f(x) = 3.99141666666667 x + 2.53499999999974R² = 0.994939944908261

DMDS

Tenax TA

Volume ( mL )

Res

pons

e

0 2 4 6 8 10 120E+00

5E+00

1E+01

2E+01

f(x) = NaN x + NaNR² = 0f(x) = NaN x + NaNR² = 0 DMS

Tenax TA

Volume ( mL )

Res

pons

e

40 60 80 100 120 140 160 180 2000E+00

1E+03

2E+03

3E+03

4E+03

5E+03

6E+03

f(x) = 32.8794 x − 487.4R² = 0.999223653337739

f(x) = 17.2322333333333 x − 515.877999999999R² = 0.999509232569337

C2H5SH

Volume ( mL )

Res

pons

e

20 40 60 80 100 120 140 1600E+00

1E+04

2E+04

f(x) = 84.15 x + 22.4999999999991R² = 0.99983697407057f(x) = 86.4466666666667 x − 665.400000000001R² = 0.998550999298153

CS2

Volume ( mL )

Res

pons

e

N=3 N=3

N=3 N=3

24

Summary• An on-line TD-GC/PFPD was developed for analyzing ambient RSCs.

• Of all the RSCs, H2S is the most difficult RSC to be enriched due to its high volatility and reactivity.

• Unibeads 1S shows significantly better sorption characteristics than MS 5A and Tenax TA to enrich H2S with LOQ = 0.17 ppbv.

• For other higher boiling RSCs, Unibeads 1S shows comparable sorption characteristics to the conventional MS 5A or Tenax TA.

• Sorbents with smaller pore sizes may reduce the formation of DEDS from C2H5SH.

• Unibeads 1S has never been used as a sorption material for RSCs, and previously it is being used as a packing material for GC columns.

25

Thanks for your attention !

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