Technologies to convert biomass to liquid hydrocarbon fuels are currently being developed to decrease our carbon footprint and increase use of renewable fuels.
Cellulose and hemicellulose are two major constituents in the biomass and can be broken down to C6 and C5 sugars using an acid or enzyme hydrolysis process. C6 and C5 sugars can be further converted to sugar alcohols or other derivatives. The sugars and their derivatives can be upgraded to gasoline range hydrocarbons, mainly aromatics, using a ZSM-5 catalyst, hydrotreating or combinations of ZSM-5 and hydrotreating.
However, the sugars and sugar derivatives from biomass have high oxygen content and low hydrogen content, and coking and frequently lower liquid yield becomes an issue during zeolite upgrading to liquid hydrocarbon fuels.
Addition of hydrogen donors with high effective hydrogen to carbon ratio such as methanol (U.S. Pat. No. 4,503,278) and i-pentane (U.S. Pat. No. 7,678,950) have been used to decrease coking, incorporated by reference. However, the cost to use methanol is high.
Therefore, developing a new process for converting sugar and sugar derivatives from biomass with reduced coking issue during zeolite upgrading to liquid hydrocarbon fuels would be a significant contribution to the art. In addition, development of a process for converting sugar and sugar derivatives to hydrocarbons which yields significant quantities of desirable hydrocarbon products such as aromatics and olefins would also be a significant contribution to the art.