Study of particulate matter at DLSU-Manila using SEM-EDX and gravimetric analysis

• Main Author: Narido, Shaira Jehsarine C.
• Format: text
• Language: English
• Published: Animo Repository 2013
• Subjects: Particulate matter—Philippines—Manila; Environmental Indicators and Impact Assessment; Environmental Monitoring
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/18607; https://animorepository.dlsu.edu.ph/cgi/viewcontent.cgi?article=19118&context=etd_bachelors
• Institution: De La Salle University

Size-segregated samples were taken at Br. Andrew Gonzales Hall rooftop using Staplex MBS-6 Sampler while PM2.5 samples were taken at DLSU Retreat House using Airmetrics PM2.5 sampler. The sampling period was from February 2011 to August 2012, with gaps in between due to shortage of filter supplies. The weather conditions during sampling were taken using the Davis weather station. The samples were mass of samples were determined to compute for the mass concentrations of particulate matter. A fraction of the samples were analyzed using the Scanning Electron Microscope (SEM). The diameters were measured using the SemAfore software while the elemental composition of particles were determined using the Energy Dispersive X-ray (EDX) feature of SEM. Multiple regression analysis was done to examine the relationship of weather parameters with mass concentration. Results showed an exponential relationship of mass concentration with the weather parameters, with the highest correlation observed in wind speed. A general positive correlation of temperature with mass concentration can imply the possibility of the role of photochemical reactions in particulate matter formation. Time period parameters also hinted the possible presence of anthropogenic activity emissions. Comparison of elemental percentages among groups showed that C, Na, Al, K, Ca, Ba, and Zn were higher in percentage than the other elements considered. No difference between Feret diameters of samples from Staplex (stages 4 to 6) and Airmetrics, indicating that the stages are equivalent. Dominance of irregularly-shaped particles was observed, hinting the possibility of secondary particle emissions.