Transcript MicroFlow - Glass Expansion

Performance of an Inert Selfaspirating Micro flow Nebulizer
Salar Samii, Jonathan A. Levine, Kaveh Kahen, and Akbar Montaser
The George Washington University
Department of Chemistry
Washington, DC 20052
Jerry Dulude and Bobby Brezni
Glass Expansion
Melbourne, Australia
Introduction
In recent years, nebulizers used in inductively coupled
plasma (ICP) spectrometry, particularly in ICPMS, operate
at lower uptake rates to enhance the transport efficiency
and to reduce oxide formation. In this study, a new PFA
nebulizer (Glass Expansion)
is examined, in terms of
droplet size and velocity distributions, at a self-aspirating
rate of 10 ml/min.
The results are compared to data
obtained for several concentric glass nebulizer.
Sample Introduction Components
Twister spray chamber
With Helix nebulizer
fitting
Conikal
AR30-1-FC2E
MicroMist
AR30-1-FM005E
OpalMist
AR30-1-PFA001
Critical Dimensions
Conikal
Gas Orifice i.d.
320 mm
Capillary i.d.
280 mm
Gas Annulus Area
12 mm
MicroMist
Gas Orifice i.d.
240 mm
Capillary i.d.
123 mm
Gas Annulus Area
16 mm
OpalMist
Gas Orifice i.d.
Capillary i.d.
360 mm
60 mm
Gas Annulus Area
55 mm
The Phase Doppler Particle Analyzer
Transmitting
probe
Ar+ laser
Fiberoptics
light coupler
Measurement
volume
Receiver
optics
Computer
Measurement
electronics
PMT
detectors
Droplet Size Distribution (Primary Aerosol)
0.8
60
0.6
0.4
20
0.2
0
D32 = 17.2
10
20
30
40
50
60
MicroMist
Diameter
(microns)
100
D32 = 7.1
60
20
OpalMIst Primary
OpalMist
D32 = 12.8
0.8
0.6
60
1
0.8
0.6
0.4
0.2
0
0
10
0.4
0.2
20
0
20
30
MicroMist Primary
40
50
60
40
50
60
40
40
50
50
60
60
Diameter (microns)
1
0.8
0.6
0.4
0.2
0
0
10
OpalMist
Primary
20
30
Diameter (microns)
1
Normalized Volume
100 1
Normalized Count
Normalized Count
0
Normalized Volume
Conikal
1001
Normalized Volume
Volume
Normalized
Normalized Count
Nebulizer GasConikal
FlowPrimary
Rate = 1.0 L/Min Solution Uptake Rate
= Natural
Conikal
Primary Aspiration
0.8
0.6
0.4
0.2
0
00
10
10
20
20
30
30
40
40
Diam eter (m (mm)
icrons)
Diameter
50
50
60
60
0
10
10
20
20
30
30
Diameter (microns)
Diameter (mm)
Droplet Size Distribution (Primary Aerosol)
Nebulizer Gas Flow Rate = 0.6 L/Min Solution Uptake Rate = 80 µL/Min
Cinikal Primary
1001
1
D32 = 19.2
0.8
0.6
60
Normalized Volume
Normalized Count
Conikal Primary
Conikal
0.4
0.2
20
0
0.8
0.6
0.4
0.2
0
0
10
20
30
40
50
60
0
10
0.6
60
0.4
0.2
20
0
0
10
20
30
40
50
60
Normalized Volume
Volume
Normalized
Normalized Count
D32 = 10.4
0.8
OpalMist
Normalized Volume
0.6
60
60
50
60
0.6
0.4
0.2
0
0
10
20
30
40
Diame tePrimary
r (microns)
OpalMist
1
D32 = 14.2
0.8
50
0.8
Diameter (microns)
100
40
1
Opalmist Primary
1
30
MicroMist Primary
MicroMist
1001
20
Diame te r (um)
MicroMist Primary
Normalized Count
Normalized Count
Diameter (um)
0.4
20
0.2
0
0.8
0.6
0.4
0.2
0
0
0
10
10
20
20
30
30
Diame te r (um)
40
40
Diameter (mm)
50
50
60
60
00
10
10
20
20
30
30
Diameter (um)
40
40
Diameter (mm)
50
50
60
60
Droplet Size Distribution (Primary Aerosol)
Nebulizer Gas Flow Rate = 0.2 L/Min Solution Uptake Rate = 80 µL/Min
Conikal Primary
Conikal Primary
1001
D32 = 27.0
0.8
1
Normalized Volume
Normalized Count
Conikal
0.6
60
0.4
0.2
20
0.8
0.6
0.4
0.2
0
0
MicroMist Primary
20
40
60
0
80
20
40
MicroMist Primary
0.6
60
0.4
0.2
20
0
0
OpalMist Primary
20
40
OpalMist
Diam
eter (m icrons)
1001
0.8
60
80
80
60
80
60
80
1
0.8
0.6
0.4
0.2
0
0
OpalMist Primary
20
40
Diam eter (m icrons)
1
D32 = 24.5
0.6
60
Normalized Volume
D32 = 23.7
0.8
0.4
20
0.2
Normalized Volume
Normalized Count
Normalized Volume
MicroMist
1001
60
Diameter (microns)
Diameter (microns)
Normalized Count
Normalized Count
0
0.8
0.6
0.4
0.2
0
0
0
20
20
40
40
Diameter (microns)
Diameter (mm)
60
60
80
80
0
0
20
20
40
40
Diameter (microns)
Diameter (mm)
60
80
Droplet Size Distribution (Primary Aerosol)
Conikal
1001
Nebulizer Gas Flow Rate = 1.0 L/Min
Uptake Rate = Natural Aspiration
D32 = 17.2
1.0 L/Min
Natural Aspiration
7.1
MicroMist Primary
Cinikal Primary
20
40
60
80
1
Normalized Count
100
Diameter (microns)
0.8
0.6 L/Min
80 µL/Min
19.2
0.6
60
0.4
0.2
20
0
Conikal
Primary
20
40
0
60
80
Normalized Count
Diameter (um)
1001
0.2 L/Min
80 µL/Min
27.0
0.8
0.6
60
0.4
0.2
20
0
00
Normalized
Count
Count
Normalized
0.8
60
0.6
0.4
20
0.2
0
0
Normalized Count
MicroMist
Normalized Count
Normalized Count
Conikal Primary
1
0.8
0.6
0.4
0.2
0
1
0.6 L/Min
80 µL/Min
10.4
MicroMist Primary
0
20
0.8
40
Diameter (microns)
0.6
60
80
0.2 L/Min
80 µL/Min
23.7
0.4
0.2
0
20
20
40
40
Diameter (microns)
Diameter (mm)
60
60
80
80
00
20
20
40
40
Diam eter (m icrons)
Diameter (mm)
60
60
80
80
Droplet Velocity Distribution (Primary Aerosol)
Conikal Primary
Conikal
300
Nebulizer Gas Flow Rate = 1.0 L/Min
Uptake Rate = Natural Aspiration
Vx = 40.8 m/s
200
200
Counts
Counts
300
300
MicroMist Primary
MicroMist
100
100
1.0 L/Min
Natural Aspiration
53.9
200
100
Conikal Primary
40
60
80
120
0.6 L/Min
80 µL/Min
29.7
Axial Velocity (m/s)
300
100
200
200
400
Counts
20
100
900
900
0
20
40
60
80
120
0.6 L/Min
80 µL/Min
32.7
Axial Velocity (m/s)
300
100
200
100
0
20
40
60
80
Axial Velocity (m/s)
600
600
MicroMist Primary
0
Conikal Primary
100
0
120
0.2 L/Min
80 µL/Min
10.1
300
300
900
20
40
60
80
100
120
0.2 L/Min
80 µL/Min
11.6
Axial Velocity (m/s)
Counts
Counts
0
00
Counts
Counts
400
400
MicroMist Primary
0
0
600
300
0
0
0
0
20
20
40
40
60
60
80
80
Axial Velocity (m/s)
Axial Velocity (m/s)
100
100
120
120
0
0
20
20
40
40
60
60
80
80
Axial Velocity (m /s)
Axial Velocity (m/s)
100
100
120
120
Droplet Velocity Distribution (Primary Aerosol)
Opal Mist Primary 1
MicroMist
Counts
200
200
Counts
300
300
0
Nebulizer Gas Flow Rate = 1.0 L/Min
Uptake Rate = Natural Aspiration
Vx = 48.9 m/s
100
100
0
Mist Primary
.680
20 Opal40
60
100
120
Axial Velocity (m/s)
Counts
450
450
0.6 L/Min
80 µL/Min
29.5
300
300
150
150
0
00
20
20
40
40
60
60
80
80
Axial Velocity (m/s)
Axial Velocity (m/s)
100
100
120
120
Droplet Size Distribution (Tertiary Aerosol)
Nebulizer Gas Flow Rate = 1.0 L/Min Solution Uptake Rate = Natural Aspiration
Conikal Tertiary
Conikal
Normalized Count
1001
D32 = 4.9
0.8
0.6
60
0.4
20
0.2
0
0
10
20
30
40
50
Normalized Count
MicroMist
Tertiary
Diameter
(microns)
MicroMist
Normalized Count
1001
D32 = 5.0
0.8
0.6
60
0.4
0.2
20
0
0
10
20
30
Opal Mist Primary 1
40
50
OpalMist
Normalized Count
Diameter (microns)
1
100
D32 = 6.1
0.8
0.6
60
0.4
20
0.2
0
0
0
10
10
20
20
30
30
Diameter (microns)
Diameter (mm)
40
40
50
50
Conclusions
1. The size and velocity of the aerosol produced by three Glass
Expansion nebulizers were examined.
2. The results showed that the MicroMist nebulizer produced the
finest primary aerosol with the smallest D32 value obtained at a
gas flow rate of 1.0 L/min.
3. The tertiary aerosol obtained at a gas flow rate of 1.0 L/min was
generally fine for all three nebulizers with the Conikal nebulizer
producing the smallest D32 values.
4. The results suggest that although the MicroMist nebulizer is
probably the most suitable nebulizer (among the three) for
direct injection nebulization in ICP, significant improvements in
terms of aerosol size distribution must be made.