In this work, we sought to find new efficient methods for reducing the sulfur content in crude petroleum coke. The action of reactive dichlorocarbene or chlorocarbene intermediates produced in the reaction of chloroform or methylene chloride and sodium hydroxide under phase transfer catalysis conditions was shown to cause the breakdown of C-S bonds of some individual sulfur compounds to give reaction products identifiable by classical methods. Furthermore, a series of experiments was conducted using crude petroleum coke with high sulfur content (4.3%) under phase transfer catalysis conditions, which showed that, under optimized conditions (by enhancing the mass transfer rate using phase transfer catalysis and/or ultrasound), the sulfur content in the original coke can be reduced to 2%, which comprises a reduction of more than 50% of the initial content.