Distribution, characterization and weathering of tarmats along the west coast of Qatar

Abstract

Oil residue in the form of tarmat (TM) deposited on the coast of Arabian Gulf countries is a major environmental concern. In this study, the current TM pollution trend along the west coast of Qatar has been assessed and compared with historical deposition trend. The range of TM distribution is 0-104 g m-1 with an average value of 9.25 g m-1. Though the current TM level is thirty-fold lesser than that was found during 1993-1997 (average 290 g m-1), the distribution pattern is similar. The chemical composition and structural characterization of TMs were studied using an ATR-FTIR spectroscopy, which indicated the presence of higher aromatic compounds in the north (N) coast TMs than those found in the northwest (NW) and southwest (SW) coasts. TM of NW coast is highly weathered compared to those found in the N and SW coasts. We found that the ATR-FTIR spectroscopic method is a rapid approach to characterize and study the weathering of TMs without any tedious sample preparation or solvent extraction.