PRELIMINARY CHARACTERIZATION OF ACID TAR DEPOSITS AT A HISTORIC SULFURIC ACID PLANT

In the mid-1800s, petroleum refineries in the U.S. primarily produced kerosene for lamps from crude oil. The distilled kerosene fraction was further refined by adding concentrated sulfuric acid to oxidize and remove higher molecular weight hydrocarbons and tars to clarify the kerosene and reduce smoke production during burning. Waste tar-laden and diluted sulfuric acid from Titusville, PA refineries was sent by rail to a factory two miles away where the tar was removed and concentrated sulfuric acid was produced by distillation. Today, the factory site remains unvegetated nearly 100 years after its closing, and the soil is highly contaminated with lead and acid tar. The acid tar is believed to provide a semi-continuous source of sulfuric acid, organic acids, and other heavy metals. The periodic warming of tar deposits exposes new surface area to contact with rainwater and generation of more contaminants associated with acid tar. In this report, we present the initial characterization of representative tar samples from the site. The tar had a dry wt of ca. 65%, a bulk density of 1.7, and contained ca. 2 and 21 g/kg total Pb and sulfate as sulfuric acid, respectively, along with detectable concentrations of As and Sb, common Pb alloying elements. Organic analysis of the tar was performed using liquid chromatography/quadrupole time-of-flight mass spectrometry (LC/Q-TOF-MS), and detected a wide range of compounds, including polyaromatic hydrocarbons. Results of these studies will be used to design feasible bioremediation approaches for the reclamation of the contaminated site.