Ethylene and Propene The Most Important Industrial Organic Chemicals

Ethylene and Propene The Most Important Industrial Organic Chemicals 

Having examined the properties of alkenes and introduced the elements of polymers and polymerization, let s now look at some commercial applications of ethylene and propene. 

Ethylene We discussed ethylene production in an earlier boxed essay (Section 5.1), where it was pointed out that the output of the U.S. petrochemical industry exceeds 5 x 10 ° Ib ear. Approximately 90% of this material is used for the preparation of four compounds (polyethylene, ethylene oxide, vinyl chloride, and styrene), with polymerization to polyethylene accounting for half the total. Both vinyl chloride and styrene are polymerized to give poly(vinyl chloride) and polystyrene, respectively. Ethylene oxide is a starting material for the preparation of ethylene glycol for use as an antifreeze in automobile radiators and in the production of polyester fibers. 

Propene The major use of propene is in the production of polypropylene. Tvwo other propene-derived organic chemicals, acrylonitrile and propylene oxide, are also starting materials for polymer synthesis. Acrylonitrile is used to make acrylic fibers, and propylene oxide is one component in the preparation of polyurethane polymers. Cumene itself has no direct uses but rather serves as the starting material in a process that yields two valuable industrial chemicals acetone and phenol. 

We have not indicated the reagents employed in the reactions by which ethylene and propene are converted to the compounds shown. Because of patent requirements, different companies often use different processes. Although the processes may be different, they share the common characteristic of being extremely efficient. The industrial chemist faces the challenge of producing valuable materials, at low cost. Success in the industrial environment requires both an understanding of chemistry and an appreciation of the economics associated with alternative procedures. 

Among the other chemicals prepared from ethylene are ethanol and acetaldehyde  

Ethanol (industrial solvent used in preparation of ethyl acetate unleaded gasoline additive) 

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ETHYLENE AND PROPENE THE MOST IMPORTANT INDUSTRIAL ORGANIC CHEMICALS... 

Rules, Laws, Theories, and the Scientific Method 237 Ethylene and Propene The Most Important Industrial Organic Chemicals 263... 

We made special mention in Section 5.1 of the enormous volume of ethylene and propene production in the petrochemical industry. The boxed essay Ethylene and Pro-pene The Most Important Industrial Organic Chemicals summarizes the principal uses of these alkenes. Most of the ethylene is converted to polyethylene, a high-molecular-weight polymer of ethylene. Polyethylene cannot be prepared by cationic polymerization, but is the simplest example of a polymer that is produced on a large scale by free-radical polymerization. 

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