Search for dissertations about: "transient alumina"

Showing result 1 - 5 of 19 swedish dissertations containing the words transient alumina.

  2. 1. Silver Alumina Catalysts for Lean NOx Reduction - Influence of Preparation Methods and Type of Reductant, with Transient Kinetic Modelling

    Author : Hannes Kannisto; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; silver; kinetic modelling; Lean NOx reduction; sol-gel; preparation method; dispersion; cluster; HC-SCR; freeze-dry; XPS; alumina;

    Abstract : The objective of this work was to compare three different preparation methods for silver alumina catalysts for lean NOx reduction. Characteristics such as catalytic activity with propene and n-octane as reductants, chemical state of the silver and silver dispersion were analyzed. READ MORE

  4. 2. Corrosion of High-Temperature Alloys in Molten Salts

    Author : Esraa Hamdy Mohamedin; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Thermal energy storage; Pre-oxidation; Carburisation; Molten salts; Phase transition; High-temperature corrosion; Alumina-forming alloys; Alkali transition metalates; Alkali aluminate; Chromia-forming alloys; Alumina; Concentrated solar power;

    Abstract : Concentrated solar power (CSP) is an interesting technology that involves storing solar energy in the form of heat and subsequently converting it into electricity. The third-generation (Gen3) CSP plants aim to operate at temperatures >700°C, necessitating the deployment of new heat storage materials that can withstand such high operating temperatures. READ MORE

  5. 3. Novel Insights into the Oxidation of High Temperature Alloys - The Role of Environment, Microstructure and Reactive elements

    Author : Nooshin Mortazavi Seyedeh; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; reactive elements; nitridation; High temperature materials; nitrides; alumina; hydrides; microstructure; chromia; oxidation;

    Abstract : The properties of materials can be deteriorated, when they react with an environment at high temperature and form various types of corrosion products, such as oxides and nitrides. In order to perform successfully at elevated temperatures, all these materials are required to be protected by a slow-growing, continuous and adherent surface oxide layer. READ MORE

  6. 4. Experimental and kinetic studies of H2 effect on lean exhaust aftertreatment processes: HC-SCR and DOC

    Author : Muhammad Mufti Azis; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HC-SCR; NO oxidation.; Hydrogen effect; NOx reduction; Kinetic modeling; Silver Alumina; DOC; Platinum Alumina;

    Abstract : With a growing concern to lower greenhouse gas emissions from road transportation, lean burn and diesel engines will keep playing an important role in the future. Development of a highly efficient and durable process to reduce NOx to N2 becomes a challenging issue especially in the presence of ample O2 concentration as in lean burn exhaust. READ MORE

  7. 5. Is water a crucial factor in the oxidation of FeCrAl alloys?

    Author : Helena Josefsson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; alpha-Al203; oxidation kinetics; high temperatur corrosion; reactive elements; FeCrAl; vater vapour; transient alumina;

    Abstract : FeCrAl alloys are much used at high temperatures because the formation of a dense and slow-growing alumina scale provides resistance towards oxidation and high temperature corrosion. While the FeCrAl alloys are primarily intended for temperatures above 950ºC, they are sometimes used at lower temperature, for example as supports in automotive catalysts. READ MORE