Flushed from its startup success with its new 200,000 tonne/year green polyethylene (PE) plant in Brazil, Braskem announced last week that it will now build a sugarcane ethanol-based polypropylene plant after concluding the conceptual phase of the project.
Work on the basic engineering studies for the plant is expected to conclude next year and operational startup of the facility is projected in the second half of 2013. Investment of the plant is around $100m and capacity is said to be a minimum 30,000 tonne/year.
Braskem did not state what particular Green PP technology will be used except that it will be an already proven technology on an industrial scale using sugarcane ethanol as feedstock. The conceptual engineering was conducted in partnership with Fundacao Espaco Eco.
The company has been looking into producing green PP since 2008 in various development partnerships including the one last year with Novozymes. At the plastic and rubber K Show in Germany, where the announcement was made, Braskem reportedly confirmed through Plastics News that it will not use the enzyme-based fermentation technologies it is developing together with Novozymes.
According to consulting firm Nexant, there are several routes where green PP can be produced:
Case 1: Fermentation of sugars to produce bio-ethanol followed by dehydration to bio-ethylene. Some of the bio-ethylene are dimerized to produce n-butene, which are then reacted to remaining bio-ethylene via metathesis to produce green PP.
Case 2: Butanol is produced either by fermentation of sugars or gasification of biomass and the bio-butanol is dehydrated to produce bio-butene. And you know the rest from Case 1...
Case 3: Bio-propane produced as a byproduct of biodiesel is dehydrogenated to produce green PP
Case 4: Vegetable oil is fed to an enhanced fluid catalytic cracker (FCC) unit to produce green PP.
Looks like the only option from bio-ethanol here is Case 1 and 2...