Experiment: 2014 FIXCIT Study_20140126_METHACROLEIN/nitrogen dioxide/methyl nitrite/methacrylic acid epoxide_Hydroxyl radical_Ammonium sulfate_Methacrolein + OH, high NO, dry, then humidify and add (NH4)2SO4 seed at end
Experiment
Name: 2014 FIXCIT Study_20140126_METHACROLEIN/nitrogen dioxide/methyl nitrite/methacrylic acid epoxide_Hydroxyl radical_Ammonium sulfate_Methacrolein + OH, high NO, dry, then humidify and add (NH4)2SO4 seed at end
Date: 2014-01-26
Organization
2014 FIXCIT Study
Chamber
Seinfeld chambers
Experiment Set
FIXCIT experiments
Goals
Understand the gas-phase products of MPAN + OH. Understand what contributes to SOA from MPAN + OH.
Summary
Within an hour of lights on, methacrolein was completely oxidized away. Significant amounts of organic aerosol were reported by AMS past 30% oxidation of methacrolein. TD-LIF reported increasing signal on their PN channel, peaking around lights off. Upon lights off, GHTOS reported significant OH interference, so the addition of NO was held off for 20 minutes. NO addition led to an excess of roughly 90ppb of NO and successfully titrated out the ozone. Wall loss was monitored for approximately an hour. MAE standard (courtesy of the Surrat group at UNC-Chapel Hill) was then injected into the chamber, at approximately ~10ppb. Wall loss was monitored again for another 90 minutes. At this point, humidified air was added to the bag to intentionally cause wall loss of MAE. Wall loss did increase after addition of humidity. Wet ammonium sulfate seed aerosol was then injected into the bag and no extra wall loss was noted from MAE.
Additional Notes
Instrument Status: all up Bag Additions: Initial: ~40ppb methacrolein (from conc. bag ~1136ppm[PNNL ref. spec]... 1x bulb @ 745.8 torr, zero 3.5 torr) ~50ppb NO2 (94.5 torr, zero 3.4 torr, mbar in FTIR: 5.238V, zero 0.701V) ~200ppb CH3ONO (8.05 torr, filled/dumped 3 aliquots before final fill) Then: MAE to ~10ppb Humidified air to final RH ~40% Wet Ammonium Sulfate (0.1M (NH4)2SO4) to ~100ug/m3 Timeline (UTC, hrs): 17:00 - bag capped, filled 17:28 - injection of methacrolein bulb 1 (5sL/m) 17:33 - stop injection of methacrolein bulb 1 17:35 - injection of methacrolein bulb 2(5sL/m) 17:45 - stop injection 18:07 - all inustrments started sampling by this time 18:30 - all instruments stop 18:34 - inject NO2 bulb 5sL/m 18:44 - injection stopped 18:51 - CH3ONO injection 19:00 - CH3ONO stopped 19:00 - everyone sampling 19:30 - UV Lights On @ 10% 22:00 - Lights off 22:19 - Adding NO for 90sec, roughly 250ppb 22:22 - Continue flushing NO line with 5sLm air for 15min 23:34 - start injecting MAE standard 25:06 - stop injecting MAE standard 25:34 - Start humidified air going into bag 26:02 - Stop humidified air going into bag, roughly ~37% RH 26:40 - Wet seed addition with a heat gun 26:49 - bag mixing 26:52 - bag mixing 26:52 - stop seed injection 27:30 - end of experiment, started flushingExperiment Details
Categories:
- Gas phase chemical reaction
- Aerosol formation
Relative Humidity: 5
Seeded Experiment: Yes
Type of Seed: Ammonium sulfate
Initial Seed Concentration Value:
Seed Concentration Units:
Fuchs Adjusted Surface Area:
Condensation sink rate coefficient: 5
Reaction type:
Oxidant Name: Hydroxyl radical
Initial Oxidant Concentration Value: 2e7 (molecules_per_cubic_centimeter)
RO2 Main Fate: NO2
RO2 Lifetime: (Seconds)
Pressure: 750
Data Sets
Data Set plots
Experiment Set Details
Name: FIXCIT experiments
Time format and units: Seconds past midnight
Description:
The Focused Isoprene eXperiment at the California Institute of Technology (FIXCIT) was a collaborative study at the atmospheric chambers of Caltech during January 2014. FIXCIT is the laboratory component of SOAS, and is aimed toward (1) better understanding the chemical details behind ambient observations relevant to the southeastern United States, (2) advancing the knowledge of atmospheric oxidation mechanisms of important biogenic hydrocarbons, and (3) characterizing the behavior of field instrumentation using authentic standards. A series of chamber experiments was conducted to investigate the oxidation of isoprene, α-pinene, methacrolein, pinonaldehyde, acylperoxy nitrates, isoprene hydroxy nitrates (ISOPN), isoprene hydroxy hydroperoxides (ISOPOOH), and isoprene epoxydiols (IEPOX). Pinonaldehyde and isomer-specific standards of ISOPN, ISOPOOH, and IEPOX were synthesized, enabling study of the oxidation mechanisms and instrument responses for these compounds.
Collaborators:
- Allen H. Goldstein UC Berkeley
- William H. Brune Penn State University
- Ronald C. Cohen UC Berkeley
- Delphine K. Farmer Colorado State University
- Manjula R. Canagaratna Aerodyne
- Douglas R. Worsnop Aerodyne
- Jose L. Jimenez University of Colorado Boulder
- Frank N. Keutsch Harvard
- Saewung Kim UC Irvine
- Alex B. Guenther UC Irvine
- John E. Mak SUNY Stonybrook
- Geoffrey S. Tyndall NCAR
- Denise D. Montzka NCAR
- Andrew J. Weinheimer NCAR
- Alam Hasson Fresno State
Contacts
Principal investigators:
Paul O. Wennberg
Phone: 626 395 2447
E-mail: wennberg@caltech.edu
OrcID: 0000-0002-6126-3854
John H. Seinfeld
Phone: 626-395-4635
E-mail: seinfeld@caltech.edu
OrcID: 0000-0003-1344-4068
John D. Crounse
Phone: 626-395-8655
E-mail: crounjd@caltech.edu
OrcID: 0000-0001-5443-729X
Tran B Nguyen
Phone: 5307525987
E-mail: tbn@ucdavis.edu
OrcID: 0000-0001-9206-4359
Data Manager:
Tran B. Nguyen
Phone: 5307525987
E-mail: tbn@ucdavis.edu
Reactants
| Reactant | Compound type | Concentration | Concentration units |
|---|---|---|---|
| METHACROLEIN |
|
43 | Parts Per Billion |
| nitrogen dioxide |
|
50 | Parts Per Billion |
| methyl nitrite |
|
200 | Parts Per Billion |
| methacrylic acid epoxide |
|
10 | Parts Per Billion |
20140126_expTimeline.csv
Timeline
| UTC_hr | Action |
| 17:00 | bag capped/filled |
| 17:28 | injection of methacrolein bulb 1 (5sL/m) |
| 17:33 | stop injection of methacrolein bulb 1 |
| 17:35 | injection of methacrolein bulb 2(5sL/m) |
| 17:45 | stop injection |
| 18:07 | all instruments started sampling by this time |
| 18:30 | all instruments stop |
| 18:34 | inject NO2 bulb 5sL/m |
| 18:44 | injection stopped |
| 18:51 | CH3ONO injection |
| 19:00 | CH3ONO stopped |
| 19:00 | everyone sampling |
| 19:30 | UV Lights On @ 10% |
| 22:00 | Lights off |
| 22:19 | Adding NO for 90sec; roughly 250ppb |
| 22:22 | Continue flushing NO line with 5sLm air for 15min |
| 23:34 | start injecting MAE standard |
| 25:06 | stop injecting MAE standard |
| 25:34 | Start humidified air going into bag |
| 26:02 | Stop humidified air going into bag; roughly ~37% RH |
| 26:40 | Wet seed addition with a heat gun |
| 26:52 | bag mixing |
| 26:52 | stop seed injection |
| 27:30 | end of experiment; started flushing |
Citations
- Overview of the Focused Isoprene eXperiment at the California Institute of Technology (FIXCIT): mechanistic chamber studies on the oxidation of biogenic compounds
- Mechanism of the hydroxyl radical oxidation of methacryloyl peroxynitrate (MPAN) and its pathway toward secondary organic aerosol formation in the atmosphere
- Can Isoprene Oxidation Explain High Concentrations of Atmospheric Formic and Acetic Acid over Forests?
Characterizations
2013-12-16 (#19)
Particle Loss Characterizations:
2013-03-24 (#10)
Vapor Loss Characterizations:
(None)
Chamber Details
Name: Seinfeld chambers
Volume in cubic meters: 22
Shape: Rectangular Prism
Surface area in cubic meters: 48
Flow Mode: Batch
Flow through rate in liters per minute:
Body Material: Teflon
Body thickness: 2
Replacement date:
Replacement frequency: As needed
Cleaning method:
Flushing with air
Flushing with air with UV lights on
Oxidation
o3 background: < 0.5 ppb
nox background: 40 ppt
Particle background in micrograms per cubic meter: < 0.01 ug/m3
Air filtration method: Custom filtration canisters to remove NOx, hydrocarbons, water, particles, ozone, SOx from pressurized ambient air.
Mixing method: 1
Mixing method material: Pulsed air jets, manually actuated
Temparature Control: Yes
Temparature measurements recorded: Yes
Temparature range (min degrees celcius): 10
Temparature range (max degrees celcius): 45
Humidity Control: Yes
Humidity Measurements Recorded: Yes
Relative humidity range (min percent): 4
Relative humidity range (max percent): 90
Particle experiment capability: 1
Lights: Yes
Light source type(s):
UV black lamps (350 nm centered)
Supplemental information: https://www.worldscientific.com/doi/abs/10.1142/9789813147355_0001
Additional Notes: