Analysis of Cations in Hydraulic Fracturing Flowback Water from the Marcellus Shale Using Ion Chromatography This presentation describes the determination of cations in hydraulic fracturing flowback water using ion chromatography. In this work, sodium was most abundant, followed by calcium, strontium, magnesium, potassium, barium, ammonium, and then lithium, respectively. The quantity of scale-forming ions, such as calcium, strontium, and barium, is particularly informative because it can be used to determine the amount of anti-scaling agent in fracturing fluid mix that will maximize hydrocarbon recovery.

1. 1
Analysis of Cations in Hydraulic
Fracturing Flowback Water from the
Marcellus Shale Using Ion
Chromatography
Art Fitchett
Director of NASS Operations and Compliance
Chromatography and Mass Spectrometry
Thermo Fisher Scientific
Bannockburn, IL
The world leader in serving science

2. Environmental Impact of Hydraulic Fracturing
2
• Challenges
• Potential for contamination of water, soil, and air
• Compliance to clean water act and shale gas regulations
• Optimization of fracturing processes
• Solution
• Water quality monitoring
• Anion and cations
• Metals
• Organics
• Radiation

3. 3
Hydraulic Fracturing Workflow
Well 1
Waste
Disposal
Desalination
Well 2
Frack Chemicals
Frack Chemicals Pre-Injection Site
assessment
Recycle
Flowback / Produced
Brines
Deep Well
Injection
Gas Production
Water
Monitoring Well Monitoring Well
Fresh Water

4. 4
Hydraulic Fracturing Workflow Monitoring
Inorganic
Metals
Anions
Organic
Surfactants
Site Monitoring Produced Water
13C-CH4 , 18O 87Sr/86Sr
stable gas IRMS HR-ICP-MS, TIMS, MC-ICP-MS
Cl-, Br-, SO4
-
IC, Discrete Analyzer
Ethoxylated phenols, acrylamide
LC-MS/MS, LC-CAD
Sr, Ba, Ca, Mn, Ar, etc.
Cations IC, AAS, ICP-OES, ICP-MS, HR-ICP-MS
Analytes
Radiation
Water Chemistry
Sediments HF Water
Composition
Frack Design
Flowback and
Wastewater
Natural Gas Methane, BTEX
GC
Gross Alpha, Beta, Gamma, Radium 226, 228
GM, NaI
Isotopes ratios
Organic acids
IC
Brines
TDS, alkalinity, pH, conductivity, DO
multiple
Instrumentation

5. Analytes in Flowback Wastewater Measured by IC
5
• Inorganic anions
• Chloride
• Impacts effectiveness of additives (reuse)
• Disrupts nitrification processes
• Bromide
• Ozonation, chlorination -> disinfection by-products: brominated
trihalomethanes, bromate
 Carcinogenic
• Sulfate
• Can disrupt anaerobic digestion processes
• Organic acids
• Formic and acetic acids
• pH balance is important for efficient fracking

6. 20
μS
6
Superior Resolution Using 4 μm Particle Size
Capillary Columns
Dionex IonPac AS11-HC-4μm
(0.4 × 250 mm Column)
Column: Thermo Scientific™ Dionex™
IonPac™ AG11-HC-4μm/
AS11-HC-4μm (0.4 × 250 mm)
Eluent Source: Thermo Scientific Dionex
EGC-KOH Cartridge (Capillary)
Eluent: 1 mM KOH for 0.01 min,
1–5 mM KOH in 15 min;
5–55 mM KOH in 25 min
Flow Rate: 15 μL/min
Inj. Volume: 0.4 μL
Temperature: 30 °C
Detection: Suppressed Conductivity,
Thermo Scientific™ Dionex™
ACES™ 300 Anion Capillary
Electrolytic Suppressor, recycle
mode
2
4
6
9
10
1314
21
19
28
27
26
25
22
30
31
0 10 20 30 40
-2
Minutes
1
3
5
7
8
11 12
15
16
17
18
20
23
24
29
32
33
34
35
36
37
38
39
40
1. Quinate
2. Fluoride
3. Lactate
4. Acetate
5. 2-Hydroxybutyrate
6. Propionate
7. Formate
8. Butyrate
9. Methylsulfonate
10. Pyruvate
11. Isovalerate
12. Valerate
13. Monochloroacetate
14. Bromate
15. Chloride
16. 2-Oxovalerate
17. Nitrite
18. Ethylphosphate
19. Trifluoroacetate
20. Bromide
21. Nitrate
22. Citramalate
23. Malate
24. Carbonate
25. Malonate
26. Citraconitate
27. Maleate
28. Sulfate
29. ɑ-Ketoglutarate
30. Oxalate
31. Fumarate
32. Tungstate
33. Phosphate
34. Phthalate
35. Arsenate
36. Citrate
37. Chromate
38. Isocitrate
39. cis-Aconitate
40. trans-Aconitate

7. 5.5
μS
7
Fast Run on the Dionex IonPac AS18-4μm Column
0 1 2 3 4 5
-0.5
Minutes
1
2
3
4
5 6
7
Column: Dionex IonPac AS18-4μm, 0.4 × 250 mm
Eluent Source: Dionex EGC-KOH Cartridge (Capillary)
Eluent: 35 mM KOH
Flow Rate: 30 μL/min
Inj. Volume: 0.4 μL
Col. Temp.: 30 °C
IC Cube Temp.: 15 C
Detection: Suppressed conductivity,
Dionex ACES 300 Suppressor, recycle
mode
Peaks: 1. Fluoride 0.2 mg/L (ppm)
2. Chloride 0.5
3. Nitrite 1.0
4. Sulfate 1.0
5. Bromide 1.0
6. Nitrate 1.0
7. Phosphate 2.0

8. Analytes in Flowback Wastewater Measured by IC
8
• Cations
• Potassium, sodium
• Impacts effectiveness of additives (reuse)
• Lithium
• Human toxicity
• Ammonium
• Corrosive
• Magnesium, calcium, barium, strontium
• Scale buildup

9. Challenge of Wastewater Analysis
9
High concentrations of dissolved salts:
• Exceed column capacity
• Poor chromatography
• Peak suppression
• Inaccurate reporting
• Exceed linear calibration range
• Analyte specific
• Inaccurate results
• Decrease column lifetime
0 2 4 11
12,000
μS
0
6 8 10
Minutes
50
μS
0
0 2 4 6 8 10 11
Minutes
Undiluted
Diluted

10. Obtaining Accurate Data From High Salt Samples
Manual Analysis
• Post-run
• Determine concentration from chromatogram peak area
10
• Exceed limit → dilute → re-run sample
• Pre-run
• Manual conductivity measurement
• Exceed limit → dilute → run sample
• Tedious
• Dilution prone to errors

11. Obtaining Accurate Data From High Salt Samples
Automated Analysis
• “AutoDilution”
• Post-run analysis using ion chromatograph software
• Exceeding peak height or area -> re-run with less sample loaded
• In-line Conductivity
• Conductivity measured prior to loading sample onto column
• Exceeding upper limit -> less sample loaded
Injecting Less Sample
• Smaller sample loop
• Partial loop
• Automated sample dilution
• Lower amount of sample loaded
11
Thermo Scientific™
Dionex™
Chromeleon™
Chromatography Data
System (CDS) Software

12. Automated Dilution: Precision and Accuracy
12
Cl (g/L) Avg. %RSD
2 6545 0.058
0.02 683.1 0.034
N = 5 injections
Draw/Dispense
Speed
(μL/sec)
Set Volume
(μL)
Liquid
Dispensed
(μg)
%RSD %Accuracy
50/25 4950 4926.9 0.0032 99.5
50/25 1980 1968.9 0.0747 99.4
10/5 50 50.5 0.38 99.0
10/5 20 20.1 0.67 98.4
N = 10 injections

13. Using a Gradient for Faster Cation Separation
2.9
μS
13
Column: Dionex IonPac CG16/CS16
columns, 5 mm i.d.
Eluent Source: Dionex EGC III MSA
cartridge
Eluent (A): 30 mM MSA
Gradient (B): 20–30 mM MSA (0–10 min)
30–55 mM MSA (10–18 min)
55 mM MSA (18–32 min)
20 mM MSA (32–38 min)
Flow Rate: 1 mL/min
Inj. Volume: 25 μL
Col. Temp.: 40 °C
Detection: Suppressed conductivity,
Thermo Scientific™ Dionex™
CERS™ 500 Cation Eletrolytically
Regenerated Suppressor,
recycle mode
Sample: Mix of standards
0
7
Minutes
1 2
3
5
4
6
7
8
1 2
3
5
4
6
8
B
A
0 10 20
30 40 50 60
Peaks:
1. Lithium 0.1 mg/L 5. Magnesium 0.5
2. Sodium 0.4 6. Calcium 1.0
3. Ammonium 0.5 7. Strontium 5.0
4. Potassium 1.0 8. Barium 5.0

14. High Resolution Cation Analysis Using a Dionex
IonPac CS16 Column at Different Flow Rates
7
14
20 μL/min 2400 psi
Minutes
μS
B
A
0 40
-1
1 2 3
4
5
20
6
C
10 μL/min 1200 psi
30 μL/min 3600 psi
Column: Dionex IonPac CS16,
2 x 250 mm x 0.5 mm ID
Eluant: 30 mmol/L MSA (EG)
Flow rate: A: 10 μL/min
B: 20 μL/min
C: 30 μL/min
Inj. volume: 0.4 μL
Temperature: 40 °C
Detection: Suppressed conductivity
Thermo Scientific™ Dionex™
CCES™ 300 Cation Capillary
Electrolytic Suppressor,
AutoSuppression, recycle
mode
Peaks: 1. Lithium 0.5 mg/L
2. Sodium 2.0
3. Ammonium 2.5
4. Potassium 5.0
5. Magnesium 2.5
6. Calcium 5.0

15. Determination of Cations in Flowback Wastewater
475
μS
6.8
μS
15
Column: Dionex IonPac CG16/CS16 columns,
5 mm i.d.
Eluent Source: Dionex EGCIII MSA cartridge
Gradient: 20–30 mM MSA (0–10 min)
30–55 mM MSA (10–18 min)
55 mM MSA (18–32 min)
20 mM MSA (32–38 min)
Flow Rate: 1 mL/min
Inj. Volume: 25 μL
Col. Temp.: 40 °C
Detection: Suppressed conductivity,
Thermo Scientific™ Dionex™ CERS™
500 Cation Electrolytically
Regenerated Suppressor, recycle
mode
Sample: 100-fold diluted flowback water, filtered,
0.2 μm
0
7 8
0 5 10 25
Minutes
0
Minutes
3
1
2
3
4
5
15
5
4
1
2
6
20
6
7
30
8
32
0 5 10 15 20 25 30
32
Peaks:
Measured Undiluted
1. Lithium 0.33 mg/L 33 mg/L
2. Sodium 330.0 33,000
3. Ammonium 1.8 180
4. Potassium 5.9 590
5. Magnesium 13.0 1,300
6. Calcium 130.0 13,000
7. Strontium 14.0 1,400
8. Barium 2.1 210

16. Change in Cation Concentration of Flowback Water
16
45,000
40,000
35,000
30,000
25,000
20,000
15,000
10,000
5,000
0
1 2 3 4 5 6 7 8 9 10
Concentration (mg/L)
Fraction
Sodium
Calcium
0 gallons 140,000

17. Change in Cation Concentration of Flowback Water
17
2,000
1,800
1,600
1,400
1,200
1,000
800
600
400
200
0
1 2 3 4 5 6 7 8 9 10
Concentration (mg/L)
Fraction
Strontium
Magnesium
Potassium
400
350
300
250
200
150
100
50
0
1 2 3 4 5 6 7 8 9 10
Concentration (mg/L)
Fraction
Barium
Ammonium
Lithium
Ion composition → wastewater reuse or treatment

18. Conclusion
• Wastewater containing high salt can be challenging to
analyze
18
Automated sample pre-screening and dilution
Accurate and consistent determination of anions,
organic acids, and cations
Formulate wastewater reuse or treatment strategy

19. Technical and Application Notes
• TN 138: Accurate and Precise Automated Dilution and In-line
Conductivity Measurement Using the AS-AP Autosampler
Prior to Analysis by Ion Chromatography
• TN 139: Determination of Anions in Fracking Flowback Water
From the Marcellus Shale Using Automated Dilution and Ion
Chromatography
• AN 1094: Determination of Cations in Hydraulic Fracturing
Flowback Water from the Marcellus Shale
19
www.thermoscientific.com/ic

20. Thank you!
20
OT71277-EN-0814S.