Limbeck Andreas, Puls Christoph, Handler Markus
Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164 AC, A-1060 Vienna, Austria.
Environ Sci Technol. 2007 Jul 15;41(14):4938-45. doi: 10.1021/es062675t.
Total and size-segregated Pt and Pd emission factors from on-road vehicles were measured in the Kaisermühlen Tunnel in Vienna, Austria. Aerosol sampling was performed simultaneously inside and outside the tunnel during April and May 2005. Analysis of the acid-digested aerosol samples was performed using a preconcentration procedure with subsequent on-line detection by electro-thermal atomic absorption spectrometry (ETAAS). Inside the tunnel distinctly increased Pt and Pd concentrations were found with highest levels in total suspended particulate matter samples and reduced concentrations in the size-segregated PM10 and PM2.5 samples. Emission factors were calculated from concentration differences between tunnel inside and tunnel outside samples, the distance between tunnel entrance and sampling location, the ventilation rate, and the number of vehicles passing through the tunnel. Emission rates observed for Pt ranged from 38 +/- 5.9 to 146 +/- 13 ng veh(-1) km(-1), whereas the emission factors of Pd varied between 13 +/- 2.1 and 42 +/- 4.1 ng veh(-1) km(-1). Variations in the emission rates were assumed to originate from alterations in traffic conditions. Size-segregated investigations revealed that the major part of Pt and Pd emissions were released in the coarse aerosol mode (size fraction > PM10), nevertheless a considerable fraction (approximately 12% and approximately 22% respectively) was emitted in the inhalable PM2.5 fraction.
在奥地利维也纳的凯泽米伦隧道中，测量了道路车辆的总铂（Pt）和钯（Pd）排放因子以及按粒径分类的排放因子。2005年4月和5月期间，在隧道内外同时进行了气溶胶采样。对酸消解后的气溶胶样品进行分析时，先采用预浓缩程序，随后通过电热原子吸收光谱法（ETAAS）进行在线检测。在隧道内，发现铂和钯的浓度明显升高，总悬浮颗粒物样品中的浓度最高，而按粒径分类的PM10和PM2.5样品中的浓度较低。排放因子根据隧道内和隧道外样品之间的浓度差异、隧道入口与采样地点之间的距离、通风率以及通过隧道的车辆数量来计算。观察到的铂排放率范围为38±5.9至146±13纳克/车辆·千米，而钯的排放因子在13±2.1至42±4.1纳克/车辆·千米之间变化。排放率的变化被认为源于交通状况的改变。按粒径分类的研究表明，铂和钯排放的主要部分以粗气溶胶模式（粒径大于PM10）释放，不过仍有相当一部分（分别约为12%和约22%）以可吸入的PM2.5粒径部分排放。
