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Peter Mølgaard Mortensen

Bio: Peter Mølgaard Mortensen is an academic researcher from Technical University of Denmark. The author has contributed to research in topics: Steam reforming & Catalysis. The author has an hindex of 15, co-authored 33 publications receiving 2518 citations.

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TL;DR: In this article, two general routes for bio-oil upgrading have been considered: hydrodeoxygenation (HDO) and zeolite cracking, where zeolites, e.g. HZSM-5, are used as catalysts for the deoxygenization reaction.
Abstract: As the oil reserves are depleting the need of an alternative fuel source is becoming increasingly apparent. One prospective method for producing fuels in the future is conversion of biomass into bio-oil and then upgrading the bio-oil over a catalyst, this method is the focus of this review article. Bio-oil production can be facilitated through flash pyrolysis, which has been identified as one of the most feasible routes. The bio-oil has a high oxygen content and therefore low stability over time and a low heating value. Upgrading is desirable to remove the oxygen and in this way make it resemble crude oil. Two general routes for bio-oil upgrading have been considered: hydrodeoxygenation (HDO) and zeolite cracking. HDO is a high pressure operation where hydrogen is used to exclude oxygen from the bio-oil, giving a high grade oil product equivalent to crude oil. Catalysts for the reaction are traditional hydrodesulphurization (HDS) catalysts, such as Co–MoS2/Al2O3, or metal catalysts, as for example Pd/C. However, catalyst lifetimes of much more than 200 h have not been achieved with any current catalyst due to carbon deposition. Zeolite cracking is an alternative path, where zeolites, e.g. HZSM-5, are used as catalysts for the deoxygenation reaction. In these systems hydrogen is not a requirement, so operation is performed at atmospheric pressure. However, extensive carbon deposition results in very short catalyst lifetimes. Furthermore a general restriction in the hydrogen content of the bio-oil results in a low H/C ratio of the oil product as no additional hydrogen is supplied. Overall, oil from zeolite cracking is of a low grade, with heating values approximately 25% lower than that of crude oil. Of the two mentioned routes, HDO appears to have the best potential, as zeolite cracking cannot produce fuels of acceptable grade for the current infrastructure. HDO is evaluated as being a path to fuels in a grade and at a price equivalent to present fossil fuels, but several tasks still have to be addressed within this process. Catalyst development, understanding of the carbon forming mechanisms, understanding of the kinetics, elucidation of sulphur as a source of deactivation, evaluation of the requirement for high pressure, and sustainable sources for hydrogen are all areas which have to be elucidated before commercialisation of the process.

1,487 citations

Journal ArticleDOI
TL;DR: In this paper, four groups of catalysts have been tested for hydrodeoxygenation (HDO) of phenol as a model compound of bio-oil, including oxide catalysts, methanol synthesis catalysts and reduced noble metal catalysts.
Abstract: Four groups of catalysts have been tested for hydrodeoxygenation (HDO) of phenol as a model compound of bio-oil, including oxide catalysts, methanol synthesis catalysts, reduced noble metal catalysts, and reduced non-noble metal catalysts. In total, 23 different catalysts were tested at 100 bar H2 and 275 °C in a batch reactor. The experiments showed that none of the tested oxides or methanol synthesis catalysts had any significant activity for phenol HDO under the given conditions, which were linked to their inability to hydrogenate the aromatic ring of phenol. HDO of phenol over reduced metal catalysts could effectively be described by a kinetic model involving a two-step reaction in which phenol initially was hydrogenated to cyclohexanol and then subsequently deoxygenated to cyclohexane. Among reduced noble metal catalysts, ruthenium, palladium, and platinum were all found to be active, with activity decreasing in that order. Nickel was the only active non-noble metal catalyst. For nickel, the effect o...

353 citations

Journal ArticleDOI
24 May 2019-Science
TL;DR: A disruptive approach to a fundamental process is described by integrating an electrically heated catalytic structure directly into a steam-methane–reforming (SMR) reactor for hydrogen production, which could correspond to a reduction of nearly 1% of all CO2 emissions.
Abstract: Electrification of conventionally fired chemical reactors has the potential to reduce CO2 emissions and provide flexible and compact heat generation. Here, we describe a disruptive approach to a fundamental process by integrating an electrically heated catalytic structure directly into a steam-methane-reforming (SMR) reactor for hydrogen production. Intimate contact between the electric heat source and the reaction site drives the reaction close to thermal equilibrium, increases catalyst utilization, and limits unwanted byproduct formation. The integrated design with small characteristic length scales allows compact reactor designs, potentially 100 times smaller than current reformer platforms. Electrification of SMR offers a strong platform for new reactor design, scale, and implementation opportunities. Implemented on a global scale, this could correspond to a reduction of nearly 1% of all CO2 emissions.

234 citations

Journal ArticleDOI
TL;DR: In this article, the progress in combining fast pyrolysis and catalytic hydrodeoxygenation (HDO) to produce liquid fuel from solid, lignocellulosic biomass is discussed.

180 citations

Journal ArticleDOI
TL;DR: In this article, the authors investigated the effects of H 2 S in the syngas feed on the performance of mixed alcohols from a K 2 CO 3 /Co/MoS 2 /C catalyst.
Abstract: The present work is an investigation of how the process conditions influence the synthesis of mixed alcohols from syngas over a K 2 CO 3 /Co/MoS 2 /C catalyst. The emphasis in the investigations is upon the effects of H 2 S in the syngas feed. However the effects of the temperature and of the partial pressures of H 2 and CO are also investigated. With or without H 2 S in the feed the pre-sulfided catalyst requires an initiation period to reach a stabilized behavior, but the duration of this period depends upon the H 2 S level. Operation with a feed containing more than 103 ppmv H 2 S leads to a fairly rapid stabilization of the product distribution and ensures that higher alcohols are the dominant reaction products. With less than 57 ppmv H 2 S in the feed the stabilization of the product distribution is much slower, and methanol is the dominant product. An investigation of the reaction kinetics indicates a high CO coverage and low hydrogen coverage. Hydrogen sulfide in the syngas feed generally promotes chain growth for both alcohols and hydrocarbons, but lowers the alcohol selectivity by enhancing the hydrocarbon formation. The highest alcohol productivity reached in these investigations was 0.276 g/g cat./h, and this was achieved at 350 °C, 100 bar, GHSV = 5244 h −1 , Feed: 49.9 vol% H 2 , 50.1 vol% CO. Finally it is found that sulfur fed to the reactor as H 2 S is incorporated into the condensed alcohol product, and the incorporation of sulfur species into the product continues for some time after H 2 S has been removed from the feed. When the catalyst is operated with an S-free syngas feed, the amount of sulfur in the condensed liquid product decreases over time, but after 35 h of operation with an S-free syngas the alcohol product still contains 340 ppmw of sulfur. Thiols appear to be the dominant sulfur compounds in the product.

126 citations


Cited by
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[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

Journal ArticleDOI
TL;DR: This paper presents a new state-of-the-art implementation of the iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Key Laborotary of Catalysis, which automates the very labor-intensive and therefore expensive and therefore time-heavy and expensive process ofalysis.
Abstract: and Fuels Changzhi Li,† Xiaochen Zhao,† Aiqin Wang,† George W. Huber,†,‡ and Tao Zhang*,† †State Key Laborotary of Catalysis, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China ‡Department of Chemical and Biological Engineering, University of WisconsinMadison, Madison, Wisconsin 53706, United States

1,977 citations

Journal ArticleDOI
TL;DR: A broad review of the state-of-the-art biomass pyrolysis research can be found in this article, where three major components (cellulose, hemicellulose and lignin) are discussed in detail.

1,613 citations