Date of Award
Master of Science in Environmental Science - (M.S.)
Chemical Engineering, Chemistry and Environmental Science
Joseph W. Bozzelli
Barbara B. Kebbekus
A method was developed to analyze C2 and C3 light hydrocarbons: Acetylene, Ethylene, Ethane, Propyne, Propylene and Propane levels in the ambient air. Chlorinated compounds which eluted within the gas chromatograph operation conditions needed for the above hydrocarbons included Freon 12 and Methylene chloride, were also monitored.
Samples were collected from two sites, one located at Carteret and one at Elizabeth New Jersey. Samples were taken from September 1988 through July 1989. The sampling method used stainless steel canisters and was set up to collect 24 hour air samples at a constant flow rate of 30-35 cm3 /min.
The ambient air samples were preconcentrated by a liquid nitrogen cryogenic trap on a gas sampling valve mounted outside the gas chromatograph and injected into the gas chromatcgraph by placing the cryoloop into an 100°C hot water bath to vaporize the compounds. The sample injected was equivalent to the concentration of 300 to 1000 ml of ambient air from the canister (volume depended on water vapor content of air).
Average levels of the specific compounds at the two sites are:
TABLE I ONE YEAR AVERAGE LEVELS OF DETECTED AMBIENT AIR COMPOUNDS COMPOUND YEAR AVERAGE CARTERET(32)
LEVELS (PPBV) ELIZABETH(38)a ACETYLENE 6.61 6.34 ETHYLENE 8.12 6.81 EHTANE 8.89 7.69 PROPYLENE 4.53 9.42 PROPANE 6.67 16.84
a. number of samples from site
A simple analysis method was developed to determine the concentrations of total Polycyclic Aromatic Hydrocarbons in airborne particulates. The samples were collected over 24 hours on a glass fiber filter by a high volume air sampler at an industrial area, Carteret in New Jersey.
The samples were treated before analysis. An ultrasonic extraction, filter disc purification and thin layer plate isolation or filter cartridge (C18 and Fluorisil) isolation were used before analysis. Three analysis methods were used for analyzing the PAH (or Benzo(a)pyrene): Thin Layer Chromatography for Benzo(a)pyrene specific analysis and UV-Absorbance Spectrometer and UV-Fluorescence Spectrometry for total PAH analysis. 137 samples were extracted by three different solvents, ethanol, methylene chloride and cyclohexane, and analyzed by three instrumental techniques.
The results are presented as the ratio of the PAH concentration to Benzo(a)pyrene concentration. We have not been able to demonstrate that our method of total PAH analysis correlates linearly with specific Benzo(a)pyrene measurements. The results of analysis cannot distinguish between the following two conclusions:
- That Benzo(a)pyrene dose not track total PAH and that the results of our analysis show the inequality of total PAH vs Benzo(a)pyrene that actually exists;
- That Benzo(a)pyrene may track total PAH but our methods of analysis are not specific to PAH, i.e. we measure additional compounds which absorb and fluoresce in the regions of the uv where this analysis was performed.
Wu, Li-Li, "Analysis of C2 and C3 hydrocarbons in ambient air. Part 1 ; Development of simple analysis for polycyclic aromatic hydrocarbons. Part 2" (1989). Theses. 1957.