FRACTIONAL DETERMINATION OF ELEMENTAL CARBON AND TOTAL SOLUBLE AND INSOLUBLE ORGANIC-COMPOUNDS IN AIRBORNE PARTICULATE MATTER BY THERMAL-ANALYSIS COMBINED WITH EXTRACTION AND HEAVY LIQUID SEPARATION

A thermal method for the fractional determination of elemental carbon (EC) and total soluble and insoluble organic compounds (TSOC and TIOC) in airborne particulate matter has been developed by the optimization of its heating schedule and the pre-separation of other thermal degra dable matter, Mixtures of cotton, sucrose or starch as model insoluble organic compounds and carbon black or activated carbon as model EC we re subjected to thermogravimetry-differential scanning calorimetry (TG -DSC), and its heating schedule was investigated to separate an exothe rmic peak of carbon generated from organic compounds from that of EC. The heating schedule with a holding step at 430 degrees C for 60 min g ave the best recoveries for such carbonaceous components. Weight losse s of 180-485 degrees C and 485-665 degrees C in TG curves were adopted for the determination of TIOC and EC, respectively. In order to deter mine TSOC and to separate thermal degradable inorganic compounds like sulfate, carbonate and hydroxide, systematic separation consisting of acetone, water and 0.1 M hydrochloric acid extraction and heavy liquid separation of its residue was applied to real samples prior to therma l analysis. The fractions were subjected to TG-DSC; EC and TIOC were s uccessfully determined fractionally.