The catalytic activity of Pd/WOx/γ-Al2O3 for hydrodeoxygenation of guaiacol

Hong, Yoon Ki; Lee, Dae Won; Eom, Hee Jun; Lee, Kwan Young

doi:10.1016/j.apcatb.2013.12.045

Cited by 133 publications

(54 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…When hydrogen activation sites are saturated, activated hydrogen species undergo spillover to Brønsted acid sites for the phenyl ring hydrogenation or hydrogenolysis of C AR O bond in reaction intermediates. This proposed reaction mechanism is also in corroboration with the findings of numerous phenolic HDO studies involving other supported transition metal catalysts …”

Section: Resultssupporting

confidence: 88%

Atmospheric hydrodeoxygenation of phenol as pyrolytic‐oil model compound for hydrocarbon production using Ag/TiO₂ catalyst

Lup

Abnisa

Daud

et al. 2019

Asia-Pacific J Chem Eng

View full text Add to dashboard Cite

Hydrodeoxygenation (HDO) kinetics of phenol over Ag/TiO 2 catalyst was investigated at 415-600 K and 1 atm. The use of oxophilic TiO 2 support has improved phenol conversion due to its preferential activation of C-O bond.Product analysis confirmed the occurrence of direct deoxygenation (DDO) and hydrogenation-dehydration (HYD) pathways to produce benzene and cyclohexane, respectively. Both phenol hydrogenolysis and hydrogenation steps are the respective rate-limiting steps for DDO and HYD pathways of phenol HDO over Ag/TiO 2 . Based on the transition state theory, negative entropy changes of activation during HDO indicated that the HDO reactants formed activated complexes that had more orderly bonding configurations prior to the hydrogenolysis, hydrogenation, and dehydration steps. Under the present conditions, the catalyst was stable after 4 hr of HDO runs and able to be regenerated via H 2 -activation and calcination in air at 553 K with at least 98.9% removal efficiency to remove coke deposits and reform Ag metal species after HDO.

show abstract

Section: Resultssupporting

confidence: 88%

Atmospheric hydrodeoxygenation of phenol as pyrolytic‐oil model compound for hydrocarbon production using Ag/TiO₂ catalyst

Lup

Abnisa

Daud

et al. 2019

Asia-Pacific J Chem Eng

View full text Add to dashboard Cite

show abstract

“…the aromatic C aryl -O bond and the aliphatic C alkyl -O bond. The HDO of guaiacol has been investigated over different metal catalysts, such as Pd, [44,45] Pt, [46][47][48][49][50] Ru, [51][52][53] and Fe [44,[54][55][56]. The product distribution seems to vary with the specific catalyst.…”

Section: Introductionmentioning

confidence: 99%

Mechanistic analysis of the role of metal oxophilicity in the hydrodeoxygenation of anisole

Tan

Wang

Long

et al. 2017

Journal of Catalysis

118

View full text Add to dashboard Cite

A combined experimental and theoretical comparative study of the hydrodeoxygenation (HDO) of anisole was conducted over Pt, Ru, and Fe metals. In the experimental part, an inert silica support was used to directly compare the catalytic activity and selectivity of the three metals at 375 ºC under H 2 flow at atmospheric pressure. In parallel, for density functional theory (DFT) calculations the close-packed Pt(111), Ru(0001), and Fe(110) surfaces were employed to compare the possible mechanisms on these metals. It was observed that over Pt/SiO 2 and Ru/SiO 2 catalysts, both phenol and benzene were the major products in a phenol/benzene ratio that decreased with the level of conversion. By contrast, over the Fe/SiO 2 catalyst, no phenol formation was detected, even at low conversions. The DFT results show that over all the three metal surfaces the dehydrogenation at the-CH 3 side group occurs before the CO bond breaking. This removal of H atoms from the-CH 3 group facilitates the activation of the aliphatic C alkyl-O bond. Therefore, it can be concluded that a common intermediate for the three metals is a surface phenoxy and the significant differences between the three metals is related to the reactivity of this surface phenoxy. That is, over Pt(111) and Ru(0001) the phenoxy intermediate is hydrogenated to phenol, which in turn, can undergo further HDO to form benzene. This result is in agreement with the experiments over Pt/SiO 2 and Ru/SiO 2 catalysts. Over these catalysts, both phenol and benzene are major products, with the selectivity to benzene increasing with conversion at the expense of phenol. In contrast, over the Fe(110) surface, the strong metal oxophilicity makes the direct cleavage of the CO bond in the surface phenoxy easier than

show abstract

“…The HDO of oxygenated products originating from hydrogenation of the benzene ring mainly took place in the temperature range of 220-280 • C on these Ni-based catalysts. The formation of alkane products was usually considered to dissociate C-O bonds by demethoxylation and dehydroxylation [44]. The detectable HDO products were mainly comprised of cyclohexane, methylcyclopentane, cyclopentane, methylolcyclopentane, methoxycyclohexane, and cyclohexanol.…”

Section: Guaiacol Hydrogenolysis Activity Of Prepared Catalystsmentioning

confidence: 99%

Efficient Hydrogenolysis of Guaiacol over Highly Dispersed Ni/MCM-41 Catalyst Combined with HZSM-5

Qiu

Weng

et al. 2016

Catalysts

View full text Add to dashboard Cite

Abstract:A series of MCM-41 supported Ni catalysts with high metal dispersion was successfully synthesized by simple co-impregnation using proper ethylene glycol (EG). The acquired Ni-based catalysts performed the outstanding hydrogenolysis activity of guaiacol. The effects of the synthesis parameters including drying temperature, calcination temperature, and metal loading on the physical properties of NiO nanoparticles were investigated through the use of X-ray diffraction (XRD). The drying temperature was found to significantly influence the particle sizes of NiO supported on MCM-41, but the calcination temperature and metal loading had less influence. Interestingly, the small particle size (≤3.3 nm) and the high dispersion of NiO particles were also obtained for co-impregnation on the mixed support (MCM-41:HZSM-5 = 1:1), similar to that on the single MCM-41 support, leading to excellent hydrogenation activity at low temperature. The guaiacol conversion could reach 97.9% at 150 • C, and the catalytic activity was comparative with that of noble metal catalysts. The hydrodeoxygenation (HDO) performance was also promoted by the introduction of acidic HZSM-5 zeolite and an 84.1% yield of cyclohexane at 240 • C was achieved. These findings demonstrate potential applications for the future in promoting and improving industrial catalyst performance.

show abstract

The catalytic activity of Pd/WOx/γ-Al2O3 for hydrodeoxygenation of guaiacol

Cited by 133 publications

References 65 publications

Atmospheric hydrodeoxygenation of phenol as pyrolytic‐oil model compound for hydrocarbon production using Ag/TiO₂ catalyst

Atmospheric hydrodeoxygenation of phenol as pyrolytic‐oil model compound for hydrocarbon production using Ag/TiO₂ catalyst

Mechanistic analysis of the role of metal oxophilicity in the hydrodeoxygenation of anisole

Efficient Hydrogenolysis of Guaiacol over Highly Dispersed Ni/MCM-41 Catalyst Combined with HZSM-5

Contact Info

Product

Resources

About

The catalytic activity of Pd/WOx/γ-Al2O3 for hydrodeoxygenation of guaiacol

Cited by 133 publications

References 65 publications

Atmospheric hydrodeoxygenation of phenol as pyrolytic‐oil model compound for hydrocarbon production using Ag/TiO2 catalyst

Atmospheric hydrodeoxygenation of phenol as pyrolytic‐oil model compound for hydrocarbon production using Ag/TiO2 catalyst

Mechanistic analysis of the role of metal oxophilicity in the hydrodeoxygenation of anisole

Efficient Hydrogenolysis of Guaiacol over Highly Dispersed Ni/MCM-41 Catalyst Combined with HZSM-5

Contact Info

Product

Resources

About

Atmospheric hydrodeoxygenation of phenol as pyrolytic‐oil model compound for hydrocarbon production using Ag/TiO₂ catalyst

Atmospheric hydrodeoxygenation of phenol as pyrolytic‐oil model compound for hydrocarbon production using Ag/TiO₂ catalyst