Green-aromatic production in typical conditions of fluidized catalytic cracking

Abstract

The production of green hydrocarbons in the standard refinery has significant potential to reduce our reliance on oil and shorten the path to sustainability. Second-generation biomass can help to achieve this objective yet presents important drawbacks. It is majorly composed of reactive compounds and features low density. These features could be overcome by previously transforming the biomass by ketalization reaction into a bio-crude mainly composed by ketal-sugar derivatives. In this work, a representative compound of the bio-crude class, i.e. 1,2:3,5-di-O-isopropylidene-α-d-xylofuranose (DX) were used in up to 50 wt.% mixtures in n-hexane was converted in a laboratory scale fluidized catalytic cracking (FCC) reactor. A commercial and a simplified FCC catalyst were used. Converting a mixture of 30% DX in n-hexane in the presence of a commercial catalyst gave 42.3% aromatics in the liquid product, while pure n-hexane gave merely 8.9%. The use of deactivated catalysts further reduced the coke yield to half of the fresh one. The nature of the coke on the spent catalyst is exclusively composed by carbon and hydrogen, demonstrating that DX is easily deoxygenated. The n-hexane conversion slight reduced in the presence of DX, and did not reduce the stability of the catalyst through micropore blocking. This work demonstrates that adding DX allows to contributes to high bio-aromatic production in FCC and that products distribution is remarkably affected by the type of catalyst used.

Understanding green-hydrocarbon production through the strategy of biomass ketalization reaction

“…According to several papers published by our group, the conversion of biomass into fuel using the regular installations of reneries can be achieved by a two-step process: production of bio-petroleum by hydrolysis-ketalization reactions of biomass followed by catalytic cracking and hydroconversion. [13][14][15][16][17][18][19][20][21]40 The results described here evidenced the existence of bimolecular reactions between DX and hydrocarbons and the primary oxygenate produced from DX. These ndings may be used to increase the efficiency of transforming green carbon into high-value products in two scenarios.…”

“…According to several papers published by our group, the conversion of biomass into fuel using the regular installations of refineries can be achieved by a two-step process: production of bio-petroleum by hydrolysis–ketalization reactions of biomass followed by catalytic cracking and hydroconversion. 13–21,40…”

“…13,16,17 A DX mixture up to 70 wt% in n-hexane was converted into aromatics by uidized catalytic cracking (FCC) in the presence of a commercial and a simplied catalyst. 18,19 In addition a significant contribution of carbohydrates to the hydrocarbons formed was shown by 13 C labeled DX studies. 16 The possibility of producing green hydrocarbons like paraffin, iso-paraffin and naphthenic compounds was demonstrated by co-processing bio-feed and hydrocarbons through hydro-conversion (HDC) using HBEA as a catalyst.…”

Hydrodeoxygenation of Xylose Isopropylidene Ketal Over Pd/HBEA Catalyst for the Production of Green Fuels

“…The former produced mainly aromatics and light olefins. The latter produced aliphatic, cyclic, and aromatic hydrocarbons ( Batalha et al, 2014 , Batalha et al, 2017 ; Pinto et al, 2019a , Pinto et al, 2019b ; Pereira et al, 2020 , Pereira et al, 2021 ). Further, the wide variety of metal/support catalysts used in the HDO process is an advantage since it enables the conversion of different biomass-derived molecules into green fuels.…”