Search for dissertations about: "hydrothermal stability"

Showing result 16 - 20 of 36 swedish dissertations containing the words hydrothermal stability.

2. 16. Colour changes and acid formation in wood during heating

   Author : Bror Sundqvist; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wood Physics; Träfysik;

   Abstract : Heating wood has since ancient times been a method to dry and modify its properties. Nowadays heat is used in industrial processes for the same reasons. Treatment at temperatures above 150ºC can change the colour, improve resistance to biodegradation and enhance dimensional stability. READ MORE

4. 17. A tandem Catalyst for hydrogenation of CO2 to light olefins — The role of the zeolite component

   Author : Wei Di; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Brønsted acid density; MTO reaction; CO2 hydrogenation; tandem catalysts; HCPs; methanol-intermediate; pre-coking; Al distribution; light olefins; SSZ-13 zeolite;

   Abstract : The catalytic conversion of waste CO2 into light olefins offers a sustainable pathway for green chemicals production in the future. Over a tandem catalyst with the bifunctional active sites for methanol synthesis (CTM) and methanol to olefins (MTO), CO2 can be efficiently converted via intermediate methanol into a mixture of light olefins (ethylene, propene, butene). READ MORE

5. 18. Enzyme Immobilization in Mesoporous Silica

   Author : Hanna Gustafsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; immobilization; lipase; Mesoporous; particle morphology; feruloyl esterase; enzyme; encapsulation; silica; pore size; trypsin;

   Abstract : Catalysts are widely used in many industries for production of chemicals, pharmaceuticals, fuels and energy. There is a need for more sustainable production processes, with reduced energy and raw material consumption together with a reduction in waste and toxic by-products. READ MORE

6. 19. The effect of framework structure on N2O formation over Cu-based zeolites during NH3-SCR reactions

   Author : Ghodsieh Isapour Toutizad; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CHA; MFI; Zeolites; SCR; Ammonium nitrate; Nitrous Oxide; BEA; Infrared spectroscopy; Catalysis;

   Abstract : Anthropogenic nitrous oxide (N2O), which is generally formed as a byproduct of industrial chemical processes and fossil fuel combustion, has attracted significant attention in recent years due to its destructive role in global warming and ozone layer depletion. Among different developed technologies applied for lean NOx reduction, the selective catalytic reduction (SCR) of NOx with ammonia (as a reducing agent) is presently the most used method. READ MORE

7. 20. Microstructural Changes in Deactivated Noble Metal Catalysts

   Author : Bertil Stenbom; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : The structural deactivation of supported noble metal catalysts has been investigated for treatments at different temperatures and in different atmospheres. The sintering rates of Pt/Al2O3, Rh/Al2O3, and Pt-Rh/Al2O3 catalysts were measured using temperature-programmed desorption of CO (CO-TPD) and transmission electron microscopy (TEM). READ MORE