Treatment with metallic copper for the removal of elemental sulfur from bitumen extracted from sedi-mentary rocks or petroleum is the most widely used method. Little attention has been paid, however, to its disadvan-tages. It was observed that copper can interact with some polar organic substances during conventional sulfur re-moval, which can strongly influence the quantitative and qualitative determination of bitumen, as has been con-firmed by interaction of long-chain fatty acids with copper. The copper soap generated was analyzed by element analysis, inductively coupled plasma optical emission spectrometry (ICP-OES), thermal analysis (TG-DSC) and Fourier Transform Infrared spectroscopy (FTIR). Mechanism of the interaction was investigated and elucidated. Our experimental results would necessitate improvement of the present method for sulfur removal and/or a search for a new one.