Abstract: | Abstract Recently, ultra-deep desulfurization of liquid hydrocarbon fuels is becoming very important worldwide not only because of the heightened interest for cleaner air and thus increasingly stringent environmental regulations for fuel sulfur content, but also because of the great need for making ultra-low-sulfur fuels used in hydrocarbon fuel process for fuel cell applications. This article is a selective review on chemistry and process concerning the ultra-deep desulfurization of liquid hydrocarbon fuels. The principles and problems for the existing hydrodesulfurization processes and the challenges, concepts, advantages, and disadvantages of various new approaches are discussed, including (1) sulfur compounds in liquid hydrocarbon fuels; (2) Reactivity and mechanistic aspect of various sulfur compounds; (3) Challenges in ultra-deep desulfurization processes; (4) Approaches to ultra-deep desulfurization process. |