Technology Profile: Production of Ethylene from Ethane

Ethylene is used almost exclusively as a building block — it is the largest-volume petrochemical produced worldwide (Figure 1). Production of ethylene grew rapidly in the middle of the 20th century, when oil and chemical companies began separating it from petroleum refinery waste gas and producing it from natural gas and ethane (obtained from byproduct refinery streams). FIGURE 1. Ethylene is the most produced petrochemical worldwide, by volume[/caption] Ethylene is mostly used as a raw material for the production of polymers and other organic chemicals in consumable end uses, especially packaging. Polyethylene (PE) is responsible for about 60% of global ethylene demand. The main class of PE produced in the world is high-density polyethylene (HDPE), which is responsible for the consumption of one-third of the available ethylene. This is followed by low-density polyethylene (LDPE) and linear low-density (LLDPE) varieties. Ethylene is stored as a liquid under high pressure or at low temperatures. However, most of the time, ethylene is directly supplied to consumers, via pipeline grids. Steam cracking Steam cracking — high temperature pyrolysis in the presence of steam — is the main technology used to make ethylene. The petroleum-based…