Renewable Gasoline Produced by Co-Cracking of Methanol and Ketones in Bio-Oil

Abstract

Most research on the upgrading of bio-oil by cracking has been done under atmospheric pressure, which results in a catalyst coke yield as high as 20 wt%. In this paper, pressurized cracking, as well as cocracking with methanol proved to be an effective solution for relieving catalyst deactivation. HZSM-5 catalyst was found to deactivate rapidly in the cracking process of pure ketones. However, when methanol was used as the co-cracking substance for ketones under 2 MPa, ketones reached a full conversion of 100 % without obvious catalyst deactivation. The highest selectivity of bio-gasoline phase from co-cracking of ketones and methanol reached a value of 31.6%, in which liquid hydrocarbons had a relative content of 97.2%. The co-cracking of hydroxypropanone and methanol had lower bio-gasoline phase selectivity but better oil phase quality (liquid hydrocarbons selectivity up to 99%) than those of cyclopentanone and methanol. Based on the experimental results, the promotion mechanism of methanol on cracking of ketones in bio-oil was illustrated by a co-cracking mechanism model.

Co-cracking of bio-oil model compound mixtures and ethanol over different metal oxide-modified HZSM-5 catalysts

“…When compared with the ETG 102 process, which has a feedstock (H/C) eff ratio of 2, due to the low 103 (H/C) eff ratio of crude bio-oil, an appropriate blending of bio-oil 104 and ethanol can take the feedstock (H/C) eff ratio into the range 105 between 1 and 2, which benefits the formation of aromatic hydro-106 carbons (1 6 (H/C) eff < 2). Our previous studies on co-cracking of 107 bio-oil model compounds (hydroxypropanone, cyclopentanone 108 and acetic acid) and alcohols over HZSM-5 produced high quality 109 oil phases under the optimized conditions [22][23][24]. Subsequently, 110 the co-cracking of a distilled fraction from bio-oil molecular distil-111 lation and ethanol was studied [25].…”

Aromatic Hydrocarbon Generation from a Simulated Bio-oil Fraction by Dual-stage Hydrogenation-cracking: Hydrogen Supply and Transfer Behaviors

“…The decomposition (or decarbonylation) of ketones could produce light olefins (Tago et al 2011). However, according to the author's previous study, the intensity of decarbonylation was limited, thus some oxygenated byproducts were generated (Wang et al 2012a(Wang et al , 2013a. In the research of CPO conversion over zeolite, Huang et al (2009) found that the conversion started from the adsorption of CPO on Brønsted acid to form an enol intermediate.…”

“…Publications have indicated some inferior cracking characteristics of individual HAc and ketones (Gayubo et al 2004;Wang et al 2012aWang et al , 2013aRamasamy et al 2014). After the hydrogenation pretreatment at 200 °C, large proportions of ketones, especially HPO, were successfully hydrogenated to alcohols.…”

“…Researchers found that by coprocessing with hydrogen-rich chemicals, such as alcohols, the cracking behaviors of bio-oil components could be improved (Valle et al 2010;Mentzel and Holm 2011). In the authors' previous studies alcohols were also introduced as the coreactants (Wang et al 2012a(Wang et al , 2013aWang et al 2014b). The results showed that alcohols could supply hydrogen to promote the conversion of components in a distilled fraction to aromatic hydrocarbon; nevertheless, because the hydrogen-lacking characteristic of this fraction is serious, high blending ratios of alcohols (greater than 60%) are often used, which affects the economy of this technique.…”

Biogasoline Production from the Co-cracking of the Distilled Fraction of Bio-oil and Ethanol

“…21,22 Therefore, a series of experiments was carried out to investigate the co-cracking behavior of the molecular DF from bio-oil with ethanol for biogasoline production.…”