Determination of source apportionment of volatile organic compounds in Ankara

Sert, Ezgi
In this study, ambient concentrations of fifty-one volatile organic compounds (VOCs) were measured to determine their current level, emission sources and contributions in both urban and suburban atmosphere of Ankara. Two sampling stations were established in Ankara, one in Ankara University (AU), Faculty of Agriculture, other in Middle East Technical University (METU). AU stations is for representing the urban atmosphere while METU represents suburban atmosphere. In these stations with canister sampling, between January 2013 and September 2015 for METU and between June 2014 and September 2015 for AU, VOCs were collected by 24-hour period. By using GC-FID technique, concentrations of VOCs were determined in gathered 559 canister samples. Mean VOC concentrations ranged between 0.09 μg m-3 (cis-2-pentene) and 24.76 μg m-3 (toluene) with average benzene concentration of 2.1 μg m-3 in AU while 0.06 μg m-3 (cis-2-pentene) and 10.09 μg m-3 (toluene) with average benzene concentration of 1.4 μg m-3 in METU. During sampling period, the annual limit of 5 μg m-3 for benzene was exceeded twenty five times in urban station and fifteen times in suburban station. Comparison study was applied to measured concentrations with: other cities in Turkey and cities around the world. Episodic changes, weekday – weekend changes and seasonal changes were examined. In addition, relationship between meteorological parameters and the measured concentrations were discussed. Finally, source apportionment study was conducted using PMF. Six different factors were identified in both stations, namely gasoline exhaust, diesel exhaust, industrial evaporation, solvent, gasoline evaporation and asphalt pavement. Gasoline exhaust factor had the highest contribution to total VOC mass in both stations (38% at each station). At urban station, gasoline evaporation and asphalt pavement activities contributions were approximately 23% each. Contribution of remaining factors (solvent, industrial evaporation, diesel) was <10%. At suburban station gasoline evaporation factor was the second highest contributor (19%), which was followed by industrial evaporation (13%), diesel (11%) and solvent (10%) factors. 
Citation Formats
E. Sert, “Determination of source apportionment of volatile organic compounds in Ankara,” M.S. - Master of Science, Middle East Technical University, 2017.