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Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
Characterization of acid tars.
Sunday A Leonard1, Julia A Stegemann, Amitava Roy
1Department of Civil Environmental and Geomatic Engineering, University College London, Chadwick Building, Gower Street, London, WC1E 6BT, United Kingdom. sunday.leonard@ucl.ac.uk
Journal of Hazardous Materials
|October 28, 2009
Summary
Acid tars from petroleum processing contain toxic organic compounds and metals like lead. This study characterizes their complex composition and heterogeneous contaminant distribution, providing crucial data on these industrial byproducts.
Area of Science:
- Environmental Chemistry
- Industrial Byproduct Characterization
- Petroleum Refining
Background:
- Acid tars are complex byproducts of petroleum and petrochemical processing using sulfuric acid.
- Limited public data exists on the detailed composition and variability of these hazardous materials.
Purpose of the Study:
- To comprehensively characterize the chemical composition and physical properties of acid tars.
- To investigate the leaching potential of contaminants from acid tars.
- To provide essential data on acid tar complexity and variability.
Main Methods:
- Gas Chromatography/Mass Spectrometry (GC/MS) for organic compound identification.
- Inductively Coupled Plasma/Optical Emission Spectrometry (ICP/OES) for elemental analysis.
- Differential Scanning Calorimetry (DSC), Fourier Transform Infrared (FTIR) spectrometry, and Scanning Electron Microscopy/Energy Dispersive X-ray (SEM/EDX) for material properties and surface analysis.
- Batch leaching tests with distilled water.
Main Results:
- GC/MS identified numerous toxic organic compounds, including polycyclic aromatic hydrocarbons (PAHs) and various organic acids.
- ICP/OES detected significant concentrations of lead (Pb).
- DSC revealed sample complexity, FTIR confirmed organic functional groups, and SEM/EDX showed heterogeneous contaminant distribution.
Conclusions:
- Acid tars are complex mixtures containing a wide range of toxic organic and inorganic contaminants.
- The heterogeneous nature of contaminants and significant lead presence highlight potential environmental risks.
- This research provides valuable, previously scarce data on acid tar composition and characteristics.
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