Light olefins such as ethylene and propylene are important building blocks for many end products like polyethylene and polypropylene. Recently market analysis shows that the demand for propylene is outgoing that of ethylene and the current supply cannot match the demand. A large proportion of propylene, about 65 wt%, is produced by steam cracking and about 30 wt% during the fluid catalytic cracking (FCC) process as a by-product.
High density polyethylene (HDPE) is a long-chain polymer or plastic. Polyethylene is the most common form of plastic in the world and can be processed in a number of ways to make it thin, flexible, fluffy or strong and hard such as with HDPE. HDPE is primarily used for wood-plastic composites such as plastic lumber. It is also blow molded to make plastic bottles, such as soda bottles.
Polypropylene belongs to the group of polyolefin and is partially crystalline and non-polar. Its properties are similar to polyethylene, but it is slightly harder and more heat resistant. It is a white, mechanically rugged material and has a high chemical resistance. The industrial production processes can be grouped into gas phase polymerization, bulk polymerization and slurry polymerization. All state-of-the-art processes use either gas-phase or bulk reactor systems.
