+
Method For Rapid
Analysis of Sulfurbearing Samples
for d34S and D33S
June 4th, 2013
Roxane Bowden (CIW)
Weifu Guo (WHOI)
Ann Bauer (MIT)
Yumiko Watanabe (PSU)
Shuhei Ono (MIT)
Marilyn Fogel (UC-Merced)
+
Motivation
 This
work was supported by the NASA Astrobiology
Institute to study organic materials of astrobiological
interest:
Coupled C, N, and S analysis of meteoric IOM
 Sulfur solution behavior and isotope fractionation at high
temperatures and pressures
 Experimental synthesis and carbon and sulfur isotopic
fractionation of single-carbon organic molecules in the CH-O-S
 The origin of D33S in Precambrian sedimentary rocks
(Archean sulfide and sulfates)
 Coupled carbon, nitrogen and sulfur isotope studies for
Biosignature Research (White Sands National
Monument)

+
Challenges
SO2 analyses of natural samples




Usually involves the inorganic
compounds of sulfide and sulfate
Need to analyze the organic
sulfur compounds as well
Current protocols involve timeconsuming, off-line extractions
and reductions of sulfurcontaining organic samples
Very few labs are analyzing D33S
on SO2
Issues with CNS analyses in general

C:N:S

Sulfur memory effects

N2, CO2 and SO2 separation on
GC column

Complications of 18O correction
+
Goals:

To provide a rapid analysis, high throughput
means for assessing D33S excursions using both
SO+ (m/z=48, 49, 50) and SO2+ (m/z=64, 65, 66)
ions.

To provide a method for the determination of
d15N, d13C, d34S, and D33S on the same aliquot
of sample
Began with the purchase of a Thermo Scientific Delta VPlus
with 6 Faraday cups in 2008, and the subsequent purchase
of an elementar vario MICRO cube in 2010.
+
Instrumentation

Vario MICRO cube elemental analyzer

Thermo Scientific Delta V Plus mass
spectrometer

Conflo III interface

GasBench II
+
Vario MICRO cube elemental analyzer

Ball valve sample drop

Ball joint and clamp fittings

L-shaped drying tube filled
with Sicapent (with indicator)

Cu tubing to the adsorption
trap

Post-adsorption trap water
trap with Sicapent

(Thanks Paul M. for the great
pictures yesterday!)
+ Vario MICRO cube – combustion and
reduction columns


Reduction tube from top to
bottom

Stainless steel fitting

2.5 cm silver wool

8 cm corundum balls

10 cm copper

0.5 cm quartz wool

12 cm support rod or
quartz wool

0.5 cm quartz wool
Differs from other
reduction columns in that
the entire length of Cu sits
in the hot zone (>850ºC)
Credit: elementar vario
MICRO cube manual
+ Run conditions : vario MICRO cube




Flow (ml/min): 200
Adsorption column: trap and purge
Pressure (mbar): ~1200
Combustion tube: 1150 °C
Reduction tube: 890 °C

O2 dosing: 70 sec

Standards for normalization:
S-1, S-3, NBS-123, NBS-127
N2
40 °C
CO2
90 °C
SO2
190 °C
Column
bake out:
280 °C
+
NCS spectrums – analysis of a single sample
N2
SO-SO2
CO2
+
NCS spectrums – pre-peak
Note: 190 vs 210ºC SO2 desorption issue
Pre-peak
+
Blank spectrums
Blank – normal NCS method; 70 sec O2 dosing
Blank – short blank method, 10 sec O2 dosing, memory carryover
Absolute isotope ratios,
R:
Ratio
Standard
106 R
R
17O/16O
VSMOW
386.72
0.00038672
33nmda
0.515
18O/16O
VSMOW
2005.2
0.00200520
36 nmda
1.900
33S/32S
CDT
7877.2
0.00787720
17nmda
0.528
34S/32S
VCDT
44162.6
0.04416260
36S/32S
"VCDT"
153.5
0.00015350
Species
Coefficient
Definition
103 Coefficient
Coefficient
Weifu
O2
B
17R2/(218R)
0.0365
3.6500E-05
3.7291E-05
SO2
G
33R/17R
20340
2.0340E+01
2.0369E+01
SO2
H = 2BGI
233R17R/34R
0.1382
1.3820E-04
1.3796E-04
SO2
I
218R/34R
93.02
9.3020E-02
9.0810E-02
d33 = d49 + (1 + 2/G) (d49 - d65)
d34 = d50 + (1 + I + H) (d50 - d66) + H (d65 - d49) + H/2G {-d66 + 4d65 - 2d49 + [(2 + G) d65 - (1+ G)d49]2}
d17 = d65 + (1 + G) (d65 - d49)
d18 = d66 + (1 + 2/I) (d66 - d50) + H/I {(1 + G) [d49 - (1 + 2/G) d65] + (2 + 1/G) d66 - d50 + (1 + G) d49 [(1 + 1/G) d49 - (1 + 2/G) d65]}
D17 = (1 + d17)/(1 + d18)0.528 -1
D33 = (1 + d33)/(1 + d34)0.515 -1
Kaiser and Rockmann, 2008
+
d34S (‰) SO2 3-cup vs SO2 6-cup
analysis
SF6
measured
3 – Cup
(n = 2)
6 – Cup
(n = 2)
Ag2S
32.7
30.75
30.98
Bulk
32.7
30.70
31.08
Ag2S
-5.0
-3.15
-0.03
Bulk
-5.0
-3.70
-0.90
Ag2S
4.3
4.40
5.74
Bulk
4.3
4.50
5.34
Samples from PSU
GR-E-KERO
AUS 493-1
AUS 493-17
3-cup
m/z
SO2+
64
65
66
6-cup
m/z
SO+
48
49
50
SO2+
64
65
66
+
d34S measurements (‰)
SO2 3-cup and SO2 6-cup
d34S Ag2S
35
y = 0.9059x + 1.0036
R² = 0.99936
30
measured
25
20
3 cups
15
10
6 cups
5
y = 0.8381x + 3.2907
R² = 0.99601
0
-5
-10
-10 -5
0
5 10 15 20 25 30 35 40
SF6 method
+
d34S and D33S (raw data) values, ‰
SF6
measured
6 – Cup
all six masses
(n = 2)
6 – Cup
50-omitted
(n = 2)
d34S
32.7
16.47
16.76
D33S
-0.14
-0.23
-0.38
d34S
32.7
16.54
16.97
D33S
-0.14
-0.22
-0.43
d34S
-5.0
-8.10
-8.81
D33S
-1.92
-1.74
-1.38
d34S
-5.0
-8.78
-9.22
D33S
-1.92
-1.41
-1.18
d34S
4.3
-3.53
-4.34
D33S
3.12
1.86
2.28
d34S
4.3
-3.85
-5.92
D33S
3.12
1.04
2.11
Sample
GR-E-KERO
Ag2S
Bulk
AUS 493-1
Ag2S
Bulk
AUS 493-17
Ag2S
Bulk
+ Comparison of d34S and D33S values
- mass 50-omitted (MATLAB)
20
d34S
15
10
D33S
2.5
2
y = 0.6934x - 6.1931
R² = 0.9944
1.5
y = 0.737x - 0.087
R² = 0.992
1
Ag2S
5
Bulk
0
y = 0.735x - 7.4633
R² = 0.9899
-5
0.5
Ag2S
0
Bulk
-0.5
y = 0.6683x - 0.0695
R² = 0.9815
-1
-1.5
-10
-2
-4
-15
-20
0
20
SF6 values, ‰
40
-2
0
2
SF6 values, ‰
4
+
D33S analysis of Ag2S and barite
Samples from PSU, MIT, UMD
Oct. 26, 2012
Sample
D33S
SF6
D33S
all six masses
D33S
65-omitted
GR-E-KERO
-0.14
2.91
(n = 2)
0.55
(n = 2)
AUS 493-1
-1.92
0.10
(n = 2)
-1.24
(n = 2)
AUS 493-17
3.12
4.86
(n = 2)
2.88
(n = 2)
2-S8-PU
2.881
4.09
(n = 3)
2.40
(n = 3)
3-S8-TSR
8.932
9.44
(n = 3)
7.62
(n = 3)
-1.3
0.89
(n = 3)
-0.71
(n = 3)
PPRG 1443
+
D33S analysis
Purified Ag2S from PSU, MIT, UMD
12.0
10.0
measured
8.0
y = 0.8036x + 0.3675
R² = 0.9965
6.0
65-omitted
4.0
6-cup
2.0
y = 0.8223x + 2.1289
R² = 0.978
0.0
-2.0
-4.0
-2.0
0.0
2.0
4.0
SF6 values, ‰
6.0
8.0
10.0
+
Comparison of post-analysis data
processing of the SO2 data
10.0
y = 0.8009x + 0.3906
R² = 0.9638
6-cup
65-omitted
8.0
66-omitted
50-omitted
6.0
measured
49-omitted
4.0
y = 0.783x - 0.1343
R² = 0.9913
2.0
y = 0.7883x - 0.0891
R² = 0.9902
0.0
y = 0.7747x - 0.5679
R² = 0.9899
-2.0
y = 0.7742x - 0.6602
R² = 0.9863
-4.0
-4.0
-2.0
0.0
2.0
4.0
SF6 values,‰
6.0
8.0
10.0
+
d15N and d13C on International, certified and
working standards
25
d15N
20
d13C
0
N-2, n=5
-5
15
y = 1.011x - 0.119
R² = 0.999
10
y = 1.1989x + 13.195
R² = 0.9912
-10
-15
5
0
-20
Acetanilide (n=10)
N-1 (n=5)
-5
Alanine (n=10)
-25
Alanine (n=10)
-10
Acetanilide (n=10)
-30
-10
0
10
Known values, ‰
20
30
-40
-20
Known values, ‰
0
+
d15N, d13C and d34S – protein standard
d15N
5.9 ‰
d13C
-27.0 ‰
d34S
6.3 ‰
Protein
(Sept. 27, 2011)
5.5
-26.6
3.1
Post maintenance
5.8
-26.8
3.7
5.9
-26.8
5.2
5.8
-27.1
7.8
5.7
-27.1
5.2
5.9
-27.2
6.4
6.1
-27.0
6.6
5.9
-27.1
6.7
5.8 ± 0.17 (n=8)
5.9 ± 0.07 (n=7)
-27.0 ± 0.21 (n=8)
-27.0 ± 0.06 (n=7)
5.6 ± 1.59 (n=8)
6.6 ± 0.13 (n=3)
5.6
-27.0
6.9
5.7
-27.2
6.1
Sample
(Sept. 28, 2011)
+
Sample
Protein
(Sept. 28, 2011)
d15N
5.9 ‰
d13C
-27.0 ‰
d34S
6.3 ‰
6.1
-27.0
6.6
5.8
-26.9
6.4
5.6
-27.0
6.5
5.9
-27.0
6.4
5.8
-26.9
6.6
5.9
-27.1
6.7
9 samples
5.9
-26.9
5.5
8 samples
6.1
-26.9
5.6
8 samples
6.2
-27.1
5.9
6.0
-27.0
6.4
6.1
-27.0
6.6
* Memory effects can
be seen in S
+
Conclusions/Summary
is possible to assess samples for D33S in a rapid, high
throughput manner.
 It
 d15N, d13C, d34S
and D33S can be determined on the
same aliquot of sample.
 Careful
post-analysis data analysis can minimize the
effects of contaminants and/or possible linearity issues.
 Greatly,
enhances the ability to study sulfur-bearing
compounds with the goal of understanding the
complete sulfur cycle.
+Acknowledgements
Woods Hole Oceanographic Institution
WeifuGuo
Massachusetts Institute of Technology
ShuheiOno
Ann Bauer
Pennsylvania State University
Hiroshi Ohmoto
Yumiko Watanabe
University of Maryland
James Farquhar
Elementar Americas, Inc
Robyn Sutka
Scott Hughes
Funding Agencies:
NASA Astrobiology Institute