Blar i Institutt for kjemisk prosessteknologi på forfatter "Venvik, Hilde Johnsen"
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Establishing Experimental and Characterization Methodology for Analyzing the Performance of Silver Catalysts for Formalin Production
Lervold, Stine (Master thesis, 2016)Formaldehyde is the essential component of wood adhesives, which can be used for a wide range of applications and is an important intermediate in the production of several fine chemicals. Industrially production of ... -
Fischer-Tropsch synthesis – Influence of aerosol – deposited potassium salts on activity and selectivity of Co based catalysts
Gavrilović, Ljubiša (Doctoral theses at NTNU;2018:104, Doctoral thesis, 2018)The effect of potassium salts (K2SO4, KNO3, KCl, K2CO3) on cobalt based Fischer-Tropsch catalysts has been studied experimentally and theoretically. In order to better understand the deactivation effect of potassium species, ... -
Fischer-Tropsch synthesis—Investigation of the deactivation of a Co catalyst by exposure to aerosol particles of potassium salt
Gavrilovic, Ljubisa; Brandin, Jan; Holmen, Anders; Venvik, Hilde Johnsen; Myrstad, Rune; Blekkan, Edd Anders (Journal article; Peer reviewed, 2018)The influence of potassium species on a Co based Fischer-Tropsch catalyst was investigated using an aerosol deposition technique. This way of poisoning the catalyst was chosen to simulate the actual potassium behaviour ... -
Inhibiting carbon growth at the initial stage of metal dusting corrosion of high temperature alloys
Guo, Xiaoyang (Doctoral theses at NTNU;2020:212, Doctoral thesis, 2020)Metal dusting corrosion is a high temperature degradation phenomenon affecting Fe-, Ni- and Co- based alloys when exposed to strongly carburizing gases (carbon activity ac > 1) at elevated temperatures (> 400˚C). The alloy ... -
Inhibition of metal dusting corrosion on Fe-based alloy by combined near surface severe plastic deformation (NS-SPD) and thermochemical treatment
Guo, Xiaoyang; Vullum, Per Erik; Venvik, Hilde Johnsen (Peer reviewed; Journal article, 2021)Combined NS-SPD and thermochemical treatment has been used to improve the metal dusting corrosion resistance of Incoloy 800. After testing under infinite carbon activity for 20−100 h, carbon was not found in the NS-SPD ... -
Initial stages of metal dusting corrosion
Hwang, Jihye (Master thesis, 2015)Metal dusting is a disintegration phenomenon of metals and alloys into fine, dust-like particles. Metal dusting can be found in different reforming units in the petrochemical industry. As well as in reforming units, it can ... -
Initial Stages of Metal Dusting Corrosion - Surface and subsurface investigation using SEM, Raman spectroscopy, and STEM
Helms, John (Master thesis, 2018)Metal dusting (MD) is a corrosion phenomenon that often occurs in industrial processes involving syngas. Carbon deposited on vessel walls gradually causes disintegration of the bulk metal. Because MD is related to carbon ... -
Interaction of hydrogen with flat (0001) and corrugated (11–20) and (10–12) cobalt surfaces: Insights from experiment and theory
Weststrate, Kees-Jan; Mahmoodinia, Mehdi; Farstad, Mari Helene; Svenum, Ingeborg-Helene; Strømsheim, Marie Døvre; Niemantsverdriet, Hans; Venvik, Hilde Johnsen (Journal article; Peer reviewed, 2019)Cobalt catalysts are used on a commercial scale to produce synthetic fuels via the Fischer-Tropsch synthesis process. As adsorbed hydrogen atoms are involved in many of the elementary reaction steps that occur on the ... -
Investigation of Fundamental Properties of Catalysts for Direct and Indirect Synthesis of DME
Risa, Kamilla Opheim (Master thesis, 2014)Dimethyl ether (DME) has potential as an environmentally friendly fuel. The main advantage of DME as a fuel lies in its clean combustion; the emissions of soot and particulate matter, as well as NOx and SOx are significantly ... -
Investigation of metal dusting corrosion process over UNS N08800 alloy
Guo, Xiaoyang; Panditha Vidana, Daham Sanjaya Gunawardana; Chen, De; Vanhaecke, Estelle Marie M.; Venvik, Hilde Johnsen; Walmsley, John (Journal article; Peer reviewed, 2017)Metal dusting corrosion is a catastrophic degradation phenomenon that initiates on metallic surfaces of chemical process equipment at elevated temperature and under carburizing atmospheres. It proceeds by a gradual breakdown ... -
Investigations of Pd3Au(100) as a catalytic model system
Hådem, Gaute Osaland (Master thesis, 2018)Catalysts are defined as materials that lowers the activation energy of a reaction, without being consumed. In heterogeneous catalysis they are commonly transitions metals which have been refined to small particles using ... -
Investigations of PdAu membranes and model systems for production of pure hydrogen
Sørvik, Linn Cecilie (Master thesis, 2015)Hydrogen production from carbon-containing energy sources can capture the CO2 on site, and therefore reduce the contribution to global warming. The only emission when energy is produced through a fuel cell is H2O. Another ... -
Kinetics and Deactivation in the Methanol Synthesis Reaction
Alam, Mahmud (Master thesis, 2011)This study is highlighting the synthesis of methanol by using Cu-based ( ) catalyst and synthesis gas, which consists a mixture of CO, CO2, H2, N2 and CH4. The catalyst was prepared as per the procedure described by the ... -
Microchannel Membrane Reactor for production of pure Hydrogen - Inhibition effects on thin self-supported Pd/Ag membranes
Johannesen, Bengt Arild (Master thesis, 2014)Hydrogen gas is one of the most produced gases in the world for industrial purposes, generally produced by methane steam reforming. The demand for clean hydrogen is rising as technology is advancing. Combining a hydrogen ... -
Monolithic, microchannel and carbon nanofibers/carbon felt reactors for syngas conversion by Fischer-Tropsch syntehesis
Holmen, Anders; Venvik, Hilde Johnsen; Myrstad, Rune; Zhu, Jun; Chen, De (Journal article; Peer reviewed, 2013)The present contribution summarizes work carried out on different microstructured reactors in the Catalysis Group at the Norwegian University of Science and Technology during the last years. The work has involved co-operation ... -
Morphology and Activity of Electrolytic Silver Catalyst for Partial Oxidation of Methanol to Formaldehyde Under Different Exposures and Oxidation Reactions
Lervold, Stine; Arnesen, Kamilla; Beck, Nikolas; Lødeng, Rune; Yang, Jia; Bingen, Kristin; Skjelstad, Johan; Venvik, Hilde Johnsen (Journal article; Peer reviewed, 2019)Electrolytic silver particles were studied in relation to its morphology changes under different reactive and non-reactive atmospheres, and its catalytic activity in oxidation of methanol to formaldehyde (MTF), carbon ... -
New insight to the effects of heat treatment in air on the permeation properties of thin Pd77%Ag23% membranes
Vicinanza, Nicla; Svenum, Ingeborg-Helene; Peters, Thijs; Bredesen, Rune; Venvik, Hilde Johnsen (Journal article; Peer reviewed, 2018)Sputtered Pd77%Ag23% membranes of thickness 2.2–8.5 µm were subjected to a three-step heat treatment in air (HTA) to investigate the relation between thickness and the reported beneficial effects of HTA on hydrogen transport. ... -
Nickel Cobalt Catalyst for Methane Abatement in Marine Machinery
Lund-Johansen, Ragnhild Brokstad (Master thesis, 2017)Natural gas vehicles (NGVs) have been suggested as an alternative to conventional vehicles in the marine sector, in order to reduce the large contribution this sector provides to greenhouse gas emissions. Natural gas has ... -
NiCo2O4 Catalyst on Commercial Low Surface Area and Synthesized High Surface Area CeO2 For Catalytic Methane Abatement in Natural Gas Engines
Selnes, Jon Arve (Master thesis, 2020)Større utnyttelse av naturgass som marint brensel blir sett på som en mulig del av den globale, men også nasjonale løsningen med tanke på å redusere utslipp av klimagasser. Dette forutsetter midlertidig at overskuddsmetan ... -
Oxidation of Methanol to Formaldehyde over Ag - Kinetic Modelling of Gas Phase Reactions using COMSOL Multiphysics
Ekholdt, Rakel Johanne (Master thesis, 2017)In this master thesis the goal was to create two COMSOL Multiphysics simulation models, one representing the laboratory scaled reactor and the other representing the industrial scale reactor, to study gas phase reactions ...