ABSTRACT
A refinery (Figure 4-1) is composed of various thermal and catalytic processes (Figures 4-2 and 4-3) to convert molecules in the heavier fractions to smaller molecules in fractions distilling at these lower temperatures (Jones, 1995). This efficiency translates into a strong economic advantage, leading to widespread use of conversion processes in refineries today. However, in order to understand the principles of catalytic cracking, an understanding of the principles of adsorption and reaction on solid surfaces is valuable (Samorjai, 1994; Masel, 1995)
Understanding refining chemistry not only allows an explanation of the means by which these products can be formed from crude oil but also offers the luxury of predictability. This is very necessary when the different types of crude oil accepted by refineries are considered. And the major processes by which these products are produced from crude oil constituents involves thermal decomposition. There have been many simplified efforts to represent refining chemistry (Figure 4-4) that, under certain circumstances, are adequate to the task. However, refining is much more complicated than such representations would indicate (Speight, 1999).
