Traceability tagging of volatile organic compound sources and their contributions to ozone formation in Suzhou using vehicle-based portable single photon ionization mass spectrometry

Abstract

Over the past few decades, the issue of atmospheric volatile organic compounds (VOCs) has garnered escalating global concern. Given that VOCs constitute significant pollutants and pivotal ozone (O3) precursors in both urban and industrial regions, delineating and quantifying their sources of emission stands as a fundamental requirement for devising and executing environmental control strategies. A mobile laboratory vehicle, equipped with a single photon ionization time-of-flight mass spectrometer (SPI-TOFMS) and a navigation system, was employed to tag the traceability of VOCs that contribute to O3 formation in Suzhou industrial park. The method exhibited a good method detection limit of 0.29 µgm-3, a mass resolution of the instrument was1500, and a correlation coefficient of 0.994. A positive matrix factorization (PMF) model was used for the VOCs source appointment. Three primary VOC source profiles were discerned: vehicular emissions, an industrial solvent, and biofuel combustion. These sources were recognized as the principal contributors to the pollution in the Suzhou. The successful utilization of SPI-TOFMS demonstrated a promising technique viable for conducting real-time and online monitoring of atmospheric VOCs. Moreover, an identification library of VOCs fingerprints from the same plant was established. This library serves as a precise point of reference for on-site VOC traceability, source apportionment estimation, and assessment of their contribution to ozone formation.