Patent attributes
The invention relates to an integrated process for producing liquid fuels, the process comprising the steps of:a) subjecting syngas with a hydrogen/carbon monoxide ratio between about 0.5 to 2.0 to Fischer-Tropsch reaction conditions in the presence of a first catalyst;b) optionally removing water and/or heavy hydrocarbons from the product stream; andc) subjecting the product from step a) or b) together with syngas of a hydrogen/carbon monoxide ratio higher than that of step a) or hydrogen to Fischer-Tropsch reaction conditions at higher temperatures than during step a) in the presence of a second catalyst, said second catalyst being selected such as to provide a higher activity than said first catalyst; wherein said first catalyst is selected such as to provide low methane selectivity and high olefins and heavy hydrocarbons selectivity. According to the invention, a third synthesis step or additional synthesis steps is added subsequent to the synthesis step c).
