ultra-high-pressure ion chromatography with suppressed ......18. thermal heating effects in...
TRANSCRIPT
The world leader in serving science
Christopher A. Pohl1, Sam Wouters2, Yan Liu1, Sebastiaan Eeltink2
1Thermo Fisher Scientific, Sunnyvale, USA 2Vrije Universiteit Brussel, Department of Chemical Engineering, Brussels, Belgium
Ultra-high-pressure ion chromatography with suppressed conductivity detection at 70 MPa using columns packed with 2.5 µm particles
2
Reagent-Free™ Ion Chromatography System – IC without Manual Eluent Preparation
Electrolytic eluent
generator
High-pressure non-metallic
pump
Sample injector(Autosampler)
H20
Separation column
Degasser
Waste
Conductivitydetector
Data management
Cell effluent
Electrolytic suppressor
Continuously regenerated trap column
3
Resin Structure Schematics Thermo Scientific™ Dionex™ IonPac™ Columns
Anionexchange
latex
1.25 µm
High crosslink core
Anion exchange latex coating
High crosslink core
Dionex Ion Pac AS17 Dionex IonPac AS16
4
Column Hardware and Media
Stainless-steel (SS) column housing
2 mm i.d. PEEK lining
IEX stationary phase
Inlet fitting
Outlet insert (exploded view)
PEEK frit
Inlet insert
Integrated capillary
Column
SS clamshell
PEEK seat
5
System Configuration
6
System Configuration
7
System Optimization
8
Injection Optimization
1.450 1.550 1.650 1.750 1.850 1.95
3 - 1.707
min
µS
2 µL PEEK VIPER
2 µL PEEK HP tubing
9
Injection Optimization
2.5
5.0
7.5
10.0
0.0 2.0 4.0 6.0
Red
uced
pla
e he
ight
Retention factor
2.5
5.0
7.5
10.0
0.0 2.0 4.0 6.0
Red
uced
pla
e he
ight
Retention factor
13.4 µL PEEK
8 µL PEEK2 µL Viper
500 nL Viper
AS17-S
1 ppm
0.5 ppm
2 ppm
24 ppm
4 ppm 2 ppm
8 ppm
6 ppm (mg/L)
10
2x150 mm 2.5 µm DionexIonPac AS16
Performance of 2.5 µm Dionex IonPac AS16 Prototype
0.00 2.50 5.00 7.50
0
1
2
3
1 - 1.417
2 - 1.997
3 - 3.030
4 - 4.190 5 - 6.610
minutes
µS
0.0 5.0 10.0 15.0
0
5
10
151 - 2.880
2 - 4.193
3 - 6.567
4 - 9.0475 - 14.547
µS
120 µL/min, 4,500 psi35 mM KOH
EGC 500
250 µL/min, 9500 psi35 mM KOH
10 kpsi prototype EEG
11
Performance Gains with Particle Size Reduction
0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.01.31.5
2.0
2.5
3.0
3.4
1 - 1.413
2 - 1.640
3 - 1.975
4 - 2.9885 - 4.123
6 - 6.478
7 - 8.008
min
µS
1.4
2.0
2.5
3.0
3.5
1 - 2.685
2 - 3.122
3 - 3.737
4 - 5.685 5 - 8.182
µS ≈ 70,000 plates/m
≈ 140,000 plates/m
Commercial 2x250 mm
4 µm DionexIonPac AS16
35 mM KOH
2x150 mm2.5 µm DionexIonPac AS16
35 mM KOH
12
Van Deemter Analysis (Optimized System)
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0.25 0.75 1.25 1.75 2.25 2.75 3.25 3.75
Red
uce
d p
late
hei
gh
tReduced linear velocity
50 μL/min
130μL/min
250 μL/min
50 μL/min
150μL/min
270 μL/min
2x150 mm 2.5 µm DionexIonPac AS16
Iodide
oxalate
2x150 mm 2.5 µm AS17-S
5.0
6.0
7.0
8.0
9.0
10.0
11.0
12.0
13.0
14.0
15.0
0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00 2.25 2.50
Pla
te h
eig
ht,
um
Linear velocity, mm/s
2x150 mm 2.5 µm DionexIonPac AS16
F-
SO42-
S2O32-
I-
SCN-
13
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.01.6
2.0
2.4
2.8
3.2
3.6
4.0
1 - 1.057
2 - 1.672
3 - 2.930
4 - 4.588
5 - 5.635
µS
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0
2.0
2.5
3.0
3.51 - 0.500
2 - 0.760
3 - 1.3004 - 2.008
5 - 2.455
minutes
µS
250 µL/min9500 psi
2x150 mm 2.5 µm DionexIonPac AS17-S
23 mM KOH(2-mm
suppressor)
2x100 mm 2.5 µm DionexIonPac AS17-S
23 mM KOH(2-mm
suppressor)
≈155,000 plates/m
400 µL/min9500 psi
≈135,000 plates/m
Fast IC Using Short Columns at the Kinetic Performance Limit
14
Comparison of 2.85 Micron Particles and 10 Micron Dionex IonPac AS17C Column
-5.0
0.0
5.0
10.0
15.0
20.0
25.0 mAU
1
RT=3.58 N=24489 Asym=1.182 PWHH=0.0773
0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.20 2.40 2.60 2.80 3.00 3.20 3.40 3.60 3.80 4.00 4.20 4.40 4.60 4.80 5.00-5.0
0.0
5.0
10.0
15.0
20.0
25.0 mAU
min
2
RT=3.65 N=12722 Asym=1.048 PWHH=0.1107
Analyte – NaNO3Column body – 2.1 x 150 mm RSParticle type/Size – EC2.85 precipitation particlesPacked at 21,000 psi in water
NaNO3 on Dionex IonPac AS17C 10 um particles, 2x250mm column
ConditionsFlow rate = 0.25 mL/minTemp = 65 ⁰CMobile phase = 15 mM NaOHDetection = UV 220 nmInjection vol. = 2.5 uL
HETP (EC2.85) = 6.13 µmReduced plate height = 2.15
HETP (Dionex IonPac AS17C) = 19.65 µm Reduced plate height = 1.97
15
UV Detection and Conductivity Detection at 30 ⁰C
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0Time [min]
-25.0
-20.0
-15.0
-10.0
-5.0
0.0
5.0
10.0
15.0
20.0
25.0Thermo Scientific™ Vanquish™ SystemColumn body = 2.1 x 150 mm RSTemp = 30 ⁰CFlow = 0.15 mL/minMobile phase = 15 mM NaOHInj. vol = 2.5 uLDetection = UV 220 nm
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.00.56
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
3.00
3.25
3.50
3.75
4.00
4.25
4.43
1 - 2.353
2 - 4.010
3 - 4.690
4 - 7.613
5 - 8.407
min
µS
178,000 n/mBr
102,000 n/mNitrite
93,000 n/m Cl
35,000 n/m F
184,000 n/mNitrate
222,000n/m
Thermo Scientific Dionex ICS-5000 SystemColumn body, 2.1 x 150 mm RSTemp = 30 ⁰CFlow = 0.15 mL/minMobile phase = 15 mM NaOHInj. vol = 2.5 uLDetection = ConductivitySuppressor = 2 mm
Reduced plate height = 1.57
Nitrate
16
van Deemter and Kinetic Plots
4
7
10
13
16
0 1 2 3 4
H(µ
m)
u0 (mm/s)0
1
10
100
2000 20000 200000t0
(min
)
N
0
1
2
3
0 20 40 60
Sign
al (µ
S)
Time (sec)
4 µm DionexIonPacAS16
4 µm DionexIonPacAS162.5 µm Dionex
IonPac AS162.5 µm DionexIonPac AS17
2.5 µm DionexIonPac AS16
2.5 µm DionexIonPac AS17
17
80°C30°C
F-
Cl-
NO3-
-1
80°C30°C
-3-3
-1
F-
Cl-NO3
-
-2
-2
30°C250 µL/min
45°C250 µL/min
3
F- - 1.045
Cl- - 1.627NO3
- - 2.828SO4
-2 - 4.017
PO4-3 - 4.903
min
µS
0.4 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5
0.5
1
2
Bert Wouters et al. (2014) JCA 1370
Consequences of New Operating Regimes: Heating Effects
18
Thermal Heating Effects in Ultra-High-Pressure IC
Percolation of a liquid through columns packed with 2.5 µm particles at ultra-high pressure induces frictional heating, which in turn induced axial and radial temperature gradients over the column• Temperature sensors connected to column end-fittings (providing quantitative information)• Heat-mapping camera for visualization
70 Mpa on SS column packed with 2.5 µm particles
Column inlet Column outlet
20
• 2.5 µm particles versus 4 µm• Efficiency doubled (plates/m)• 2-3 times faster (maintaining plates/column)• Highly efficient: enables reduction of column length• 100 mm column operated at kinetic performance limit: 25% loss in plates/column, but 5 times faster
• Future requirements• Ultra-low dispersion suppressor• Low dispersion conductivity cell• Column oven with still air mode
• High pressure compatible upgrade requirements• Inert pump• Eluent generator, degasser and electrolytic trap column• Injection valve and tubing• Column hardware
Conclusions