Technical assessment of the integrated “green” propylene production process from bioethanol: The Brazilian scenario as a case study

Climate change and concerns about the future of oil prices and depletion of non-renewable fossil fuels have motivated the search for alternative sources of energy. In this context, bioethanol become a viable and realistic alternative source of energy and not only restricted to ethanol fuel, but also incorporate ethanol as a raw material to be used in many sectors of transformation industry. Currently, Brazil is in a privileged position with respect to the bioethanol production from renewable resource. The optimization of current processes for obtaining bioethanol may lead to cheaper and competitive production processes, thus favoring the production of bioproducts derived from bioethanol, especially propylene. Propylene is an important feedstock for chemical and petrochemical industries and is traditionally obtained as an ethylene by-product in steam crackers and through the fluid catalytic cracking (FCC) process. Another alternative to produce propylene is through renewable resources. The most promising is via bioethanol route. In this route, the sugars are fermented to produce bioethanol, followed by dehydration to bioethylene. A portion of the ethylene is dimerized to produce normal butenes, which are reacted with the remaining bioethylene via metathesis to produce propylene. In this work the simulation of the integrated "green" propylene production process from bioethanol was performed. The objective was to assess the technical feasibility considering the Brazilian scenario as a case study. The simulation was carried out with the aid of Aspen Plus^TM platform.