Biohydrocarbons Production under Standard Refinery Conditions by means of a Representative Ketal Compound of Biocrude

Abstract

AbstractAny standard oil refinery is based on mature processes that have been adapted to poorly reactive hydrocarbon feeds. In contrast, biomass‐derived compounds are highly functionalized and reactive compared to hydrocarbons. The goal to connect these two different chemical worlds is simple: to transform biomass by ketalization under mild conditions (≈120 °C) to afford a biocrude that is composed of ketal derivatives; 1,2:3,5‐di‐O‐isopropylidene‐β‐d‐xylofuranose (DX) is present in the range of 20–30 wt % in biocrude. Herein, DX mixed in n‐hexane was used as a model under cracking and hydrotreatment conditions. A mixture of DX up to 30 wt % in n‐hexane was converted at 500 °C in fixed‐bed reactor under continuous flow using ZSM‐5 and USY zeolites as catalysts. Remarkably, ZSM‐5 was able to convert DX into monoaromatics. At 1.5 min residence time, 64–94 % of DX was converted into monoaromatics. Additionally, ZSM‐5 showed a coke yield lower than 4 wt %. In contrast, USY increased the coke yield by 10‐fold and afforded fewer monoaromatics. A DX mixture up to 30 % in n‐hexane was converted fully by hydrotreatment in a fixed‐bed reactor using Pd‐USY as the catalyst at 300 °C and 30 bar to produce saturated hydrocarbons only up to 12 atoms. 13C‐labeled DX (in all 13C‐xylofuranose) showed indubitably that xylofuranose carbon atoms were converted into hydrocarbons.