TABLE OF CONTENTS Environmental regulations on nitrogen in transportation fuels have been impacted due to the restrictions imposed on levels of nitrogen oxides released from vehicles. As mentioned earlier in this chapter, direct restrictions have been imposed on sulfur.
The Environmental Protection Agency (EPA) has proceeded with a tough rule to slash the sulfur emissions from motor vehicles, with the trend converging to zero sulfur. It is currently believed that a reduction in sulfur via hydrotreatment concomitantly leads to a nitrogen reduction. However, it is also accepted that hydrotreatment alone could achieve required sulfur removal at a very high cost. Thus, although, there is no direct rule defined by EPA on nitrogen content in fuels, the maximum NOx concentration allowed in emissions would require introduction of a denitrogenation process.
Due to the environmental constraints and the fluctuating oil prices, newer, alternative fuels are bound to be introduced. The new technology of hybrid cars and fuel-cell based cars will induce a change in the fuel pallette. However, the use of petroleum-based fuels will not be significantly reduced, since the demand for energy is going to rise at a rapid pace, and even with addition of renewable and newer cleaner fuels, the demand may not be met. What the newer technology will result is, in a greater demand on the quality of petroleum fuels. Therefore, the specifications of the future petroleum fuels will be very low in nitrogen, sulfur, etc. Quantitation as well as speciation of the components in fuels will...
