Experiment: Caltech Atmospheric Chamber_20130420_ISOPRENE/CYCLOHEXANE_Ozone_No Seed_Dry

Experiment

Name: Caltech Atmospheric Chamber_20130420_ISOPRENE/CYCLOHEXANE_Ozone_No Seed_Dry
Date: 2013-04-20

Organization
Caltech Atmospheric Chamber

Chamber
Near/Far Bag 2012-2015 (Tran)

Experiment Set
Isoprene ozonolysis (various amounts of water, SO2)

Goals
This experiment was performed to study product formation from stabilized Criegee intermediates in the Isoprene + ozone under dry conditions with cyclohexane as an OH scavenger

Summary
Start of the water series. Using 50 ppm cyclohexane to scavenge more OH. Experiment produced significant HMHP even though it was dry.

Experiment Details

Categories:

  • Gas phase chemical reaction
Temperature: 24
Relative Humidity: 4
Seeded Experiment: No
Fuchs Adjusted Surface Area:
Condensation sink rate coefficient: 4
Reaction type:
Oxidant Name: Ozone
Initial Oxidant Concentration Value: 590 (parts_per_billion)
RO2 Main Fate: Not Sure
RO2 Lifetime: (Seconds)
Pressure: 750 Torr

Data Sets

ID Instrument File  
3525 CIMS 130420_CIMS_ppb.csv
3526 GC - FID 130420_GCFID.csv
3527 O3NOxTRH 130420_gasanalyzer.csv

Data Set plots
Choose a file: Choose the X-Axis:

Experiment Set Details

Name: Isoprene ozonolysis (various amounts of water, SO2)
Time format and units: Experiment time (minutes, local)
Description:
Investigations into the humidity-dependent ozonolysis of isoprene to form hydroxymethylhydroperoxide (HMHP), formic acid, and other products. The bimolecular fates of the C1 stabilized Criegee (CH2OO) was explored with water and SO2 to understand its competition in the atmosphere.

Collaborators:

  • Tran Nguyen UC Davis
  • Paul Wennberg Caltech

Download

Download this Experiment (45.11 KB)

Contacts

Principal investigator:

John H Seinfeld
Phone: (626) 395-4635
E-mail: seinfeld@caltech.edu
OrcID: https://orcid.org/0000-0003-1344-4068

Data Manager:

Stephanie Kong
Phone: 626-395-3194
E-mail: wkong@caltech.edu

Reactants

Reactant Compound type Concentration Concentration units
ISOPRENE (6557)
  • Alkene
 99 Parts Per Billion
CYCLOHEXANE (8078)
  • Alkane
 50 Parts Per Million

130420_Timeline.csv Timeline

Local time (hh:mm) Action (Time zero is the time Isoprene is introduced)
11:55 Inject ozone
14:40 Stop ozone injection and introduce mixing air
14:50 Hooked up ozone monitor to chamber
14:55 Inject 5.5mL of cyclohexane as OH scavenger (approx 50 ppm)
15:20 Inject 10uL of isoprene or approx 100 ppb (reaction start)
21:20 Stop data collection

Citations
Cite this experiment: Publication associated with this experiment:

Characterizations
Light Flux Characterizations:
(None)
Particle Loss Characterizations:
(None)
Vapor Loss Characterizations:
2016-05-11 (#10)

Chamber Details

Name: Near/Far Bag 2012-2015 (Tran)
Volume in cubic meters: 27
Shape: Rectangular Prism
Surface area in cubic meters: 41.8
Flow Mode: Batch
Flow through rate in liters per minute:
Body Material: Teflon
Body thickness: 50
Replacement date:
Replacement frequency: As needed
Cleaning method: Flushing with air
o3 background: 0.5 ppb
nox background: 0.1 ppb for Near, > 0.1 ppb for Far
Particle background in micrograms per cubic meter: < 0.1 ug/m3
Air filtration method: Custom Filter
Mixing method: 0
Mixing method material:
Temparature Control: Yes
Temparature measurements recorded: Yes
Temparature range (min degrees celcius): 20
Temparature range (max degrees celcius): 45
Humidity Control: Yes
Humidity Measurements Recorded: Yes
Relative humidity range (min percent): 5
Relative humidity range (max percent): 100
Particle experiment capability: 1
Lights: Yes
Light source type(s): UVA Black Lamps
Supplemental information: https://www.worldscientific.com/doi/abs/10.1142/9789813147355_0001
Additional Notes: