Cooperative development of analytical methods for diesel emissions and particulates solvent extractables, aldehydes and sulfate methods

The Chemical Characterization Panel of the Coordinating Research Council Air Pollution Research Advisory Committee (CRC-APRAC) In house 1-64 Project Group (CAPI 1-64) conducted an extensive study of analytical methods for measuring diesel exhaust emissions. This report details the procedures developed for three of the non-regulated emissions. The first method, solvent extraction of particulate filters, recommends soxhlet extraction with either methylene chloride or toluene-ethanol, depending on the end use of the extract fraction. The second method involves collection of gas phase aldehydes in an acetonitrile-2, 4-dinitrophenylhydrazine solution followed by HPLC-UV analysis. The third method utilizes ion chromatography for analysis of particulate sulfate content. Round-robin testing by 18 Chemical Characterization Panel participants established precision and accuracy data that define the engineering applicability of the test methods.