Polyester from Refinery Products and Natural Gas

The largest-volume organic chemical is ethylene, an intermediate building block in many chemicals and polymers. Polyethylene is the largest of these uses, and polyester is a very 

However, in contrast to fuels, petrochemicals intermediates must be produced at extremely high purities. For example, CO at ppm levels will poison polyethylene catalysts, and acetylene in ethylene at this level will produce a crosslinked polymer that will have unsatisfactory properties. Therefore, the chemical engineer must produce these intermediates with extremely high purities, and this requires both careful attention to minor reactor products and to efficient separation of them from the desired product. These factors are also important in the economics of petrochemicals. 

A flow sheet of the steps in forming polyester is as follows  

Natural gas is primarily methane, but it contains 5-10% of natural gas hquids, primarily ethane, propane, and butane. These are available at essentially the cost of natural gas heating except for the cost of condensing these less volatile components from methane. Natural gas liquids are a major source of chemicals, along with petroleum, and we wiU describe a number of similar examples in this book. 

Reaction Rates, the Batch Reactor, and the Real World 

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