Production of Ethylene from Renewable Feedstock

Before the growth of the oil industry, starting after the Second World War, several chemicals were produced from renewable resources such as agricultural crops. Now, 

There are several ways to synthesize ethylene but only a few have been in commercial use. The most common have been  

Dehydration of ethanol was the first experiment that yielded a gas rich in ethylene from ethanol [9]. By using sulfuric acid as catalyst Dutch chemists had demonstrated the formation of ethylene in 1795 [9]. Later on this was developed to commercial production, first using phosphoric acid and later aluminium oxide as catalyst. Before the Second World War this was how ethylene was produced by removal of water from ethanol on a commercial scale, although in much smaller units than the steam crackers of today. In markets with low availability of fossil fuel or with abundant low-cost biomass, such as India and South America, this technology was used well into the 1980s. However, the relative cost of petroleum made the ethanol-to-ethylene process noncompetitive and the production plants were closed. 

During the 1950s the petroleum industry experienced a rapid development. A new abundant and cheap feedstock, naphtha, became available for the chemical industry and all ethylene needed for polyethylene and other chemical products started to be made from fossil feedstock. Combined with the development of cracker technology this has led to the very cost-effective steam crackers operated today. A typical size of a cracker built today has an ethylene production capacity of up to 1 metric tonnes/year. Gradually ethane and propane obtained either by separation from natural gas or from flare gas in oilfields have been used as feedstock. In areas with large oilfields and low population the latter provides a cheap feedstock. This is an important reason why most of today s investments in cracker capacity are made in the Middle East. 

Today there are several reasons to consider the use of renewable feedstock for the production of ethylene as discussed above. Several options can then be considered, although the most obvious are  

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