|
 |
|
Stability and Concentration Verification of Ammonium Perchlorate Dosing
Solutions
DAVID T. TSUI, USAF, Capt
ARFL/HEST, Bldg 79
2856 G Street
Wright-Patterson AFB, OH 45433
Latha Narayanan Mantech Geo-Centers Joint Venture
P.O. Box 31009
Dayton, OH 45437-0009
David Mattie, Ph.D.
AFRL/HEST, BLDG 79
2856 G Street
Wright-Patterson AFB, OH 45433
Methods
- Dionex DX-300, CDM-3, ASRS-II
- AI-350 Autosampler
- AS-11/AG-11 IC/Guard Column, and ATC-1 Anion Trap
- 45 mM NaOH in 55/45 H2O/CH3OH
- 1 mL/min Flow Rate
- 50 mL Injection Volume
- 10 mL/min Regenerant Flow Rate
Stability Solutions
- 50 ppb and 200,000 ppb Stocks Prepared in 4L Polyethylene Carboys
- 4 French Clear Square Bottles
- 3 French Amber Square Bottles
- Bottles were stored on Animal Cages
Study Conditions
- Temperature: 70 to 72 degrees F
- Relative Humidity: 60 to 65%
- 12/12 Light/Dark Cycle
- Litemate III Model 504 Lite Meter
- Day 7, 15, 36, 50, 61, and 109.
Method Validation Data
Retention Times
- Nitrate: 2.3 min
- Perchlorate: 9.4 min
Peak Width at Half Height
- Nitrate: 0.3 min
- Perchlorate: 0.4 min
| Perchlorate |
Nitrate |
| Data Points |
Conc. (mg/mL) |
Data Points |
Conc. (mg/mL) |
| 1 |
0.050 |
1 |
0.048 |
| 2 |
0.050 |
2 |
0.051 |
| 3 |
0.052 |
3 |
0.051 |
| 4 |
0.054 |
4 |
0.051 |
| 5 |
0.050 |
5 |
0.052 |
| 6 |
0.050 |
6 |
0.048 |
| 7 |
0.050 |
7 |
0.049 |
| 8 |
0.049 |
8 |
0.050 |
| Avg. Conc.( g/mL) |
0.051 |
Avg. Conc.( g/mL) |
0.050 |
| Expected Conc. ( g/mL) |
0.050 |
Expected Conc. ( g/mL) |
0.050 |
| % Recovery |
101% |
% Recovery |
100% |
| Standard Deviation |
0.002 |
Standard Deviation |
0.002 |
| MDL ( g/mL) |
0.005 |
MDL ( g/mL) |
0.005 |
| PQL (10Xmdl) |
0.05 |
PQL (10Xmdl) |
0.05 |
Code of Federal Regulations 40, Chapter 1, Pt.
136, Appendix B
- Calibration Curves: 0.05, 0.1, 0.25, 0.5, 1.0, 2.0, 5.0, 10.0, 25.0, 50.0,
100, 200 ug/mL (Not Shown, Boringly Linear)
- Linearity: MDL to 40,000 x MDL
- Correlation Variation: 0.9999
- Calibration Curves were Verified by 2nd Source
0.05 mg/mL PERCHLORATE SOLUTION IN CLEAR BOTTLE
|
Day 7 |
Day15 |
Day36 |
Day50 |
Day 61 |
Day 109 |
| Bottle A |
0.048 |
0.050 |
0.051 |
0.050 |
0.050 |
0.050 |
| Bottle B |
0.050 |
0.051 |
0.048 |
0.049 |
0.051 |
|
| Bottle C |
0.051 |
0.050 |
0.048 |
0.051 |
0.051 |
0.050 |
| Bottle D |
0.052 |
0.049 |
0.050 |
0.050 |
0.049 |
|
|
| ANOVA: Single Factor, a = 0.05 |
| SUMMARY |
| Groups |
Count |
Sum |
Average |
Variance |
| Day 7 |
4 |
0.201 |
0.050 |
2.9E-06 |
| Day15 |
4 |
0.200 |
0.050 |
6.7E-07 |
| Day36 |
4 |
0.196 |
0.049 |
1.9E-06 |
| Day50 |
4 |
0.201 |
0.050 |
5.2E-07 |
| Day61 |
4 |
0.201 |
0.050 |
9.2E-07 |
| Day109 |
2 |
0.100 |
0.050 |
0 |
|
| ANOVA |
|
| Source of Variation |
SS |
df |
MS |
F |
P-value |
F crit |
| Between Groups |
4.51E-06 |
5 |
9.02E-07 |
0.69858 |
0.63236 |
2.85241 |
| Within Groups |
2.07E-05 |
16 |
1.29E-06 |
|
|
|
| Total |
2.52E-05 |
21 |
|
|
|
|
An one way analysis of variance (ANOVA) analysis, shown on the bottom of
each table, was employed to examine the differences of within group (intra-day)
and between groups (inter-day) concentration variations. As shown in Appendix
A, three categories of sums of squares (SS) are presented in the ANOVA summary
report, along with the degrees of freedom (df) for the between and within
variance. The mean square (MS) and the test for homogeneity of variance
(F-ratio) were calculated from SS and df by the following equations: MS = SS/df
and F-ratio = between MS/ within MS. The F critical values at 0.05 rejection
level (a) were obtained from Reference 13.As compared to the appropriate
F-critical values, the small F-values (test of homogeneity of variance) for all
four sets of data indicated that ammonium perchlorate in aqueous solution at
0.05 and 200 mg/mL is stable for 109 days. At a given level, no trend was
observed in the perchlorate concentration, as some might expect an increasing
trend due to evaporation. Furthermore, no significant perchlorate concentration
difference was noted between the solutions stored in amber and clear water
bottles at a given concentration. Since the amber bottles are impermeable to
light and UV radiation, the results indicated that average 12-hour daily
exposure to light does not lead to the degradation of perchlorate in reagent
water.
Conclusion:
Ion chromatographic analysis of the stability solutions showed that under
controlled room temperature, relative humidity and light intensity, ammonium
perchlorate is stable in reagent water for at least 109 days.
Emerging Issues
- Alternative Method(s) for Perchlorate Analysis
- Triple Sector Quadrupole Mass Spectrometry (TSQ) - Intra-Laboratory
Validation
- Coulometric Detection - Feasibility Study
- Biological Matrices
- Blood, Urine, and Thyroid
- Plants, Vegetables, and Fruits
- Environmental Matrices
- Waste Water
- Storm Water
- Effects of Organic Solvents on Method Performance
- Effects of Cation(s) on Method Performance
Triple Sector Quadrupole (TSQ) Mass Spectrometry for Perchlorate
Analysis
- Instrumentation: Fin. 700 TSQ
- Mobile Phase (MP): 0.5% acetic acid in CAN
- Flow Rate: 75 uL/min
- Injection Volume: 10 uL
- Negative Ion Mode
- Qualitative Identification:
- Mass Spectra of Perchlorate in MP:
- 99 and 101 m/z - ClO4- and Isotope
- 140 m/z - CH3CN*ClO4- adduct
- 159 m/z - AcOH*ClO4- adduct
- Mass Spectra of Other anions
- Showed no overlapping m/z ratio.
- Quantitation:
- Selective Ion Monitoring (SIM) of 99 m/z
- Linear from 1 to 100 ppb
- Method detection limit: 1 ppb
|
