Search for dissertations about: "Chemical modification"

Showing result 1 - 5 of 450 swedish dissertations containing the words Chemical modification.

2. 1. Isolation and chemical modification of arabinoxylan and galactoglucomannan

   Author : Linda Härdelin; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tg; Films; Material properties; Isolation; Etherification; Modification; PEGylation; Hemicellulose;

   Abstract : Today’s society is based on the use of fossil fuels, where oil is used as transportation fuel and as raw material in the petrochemical industry. Efforts are made to increase the use of bio-based materials, since oil is a non-renewable source and a greenhouse gas contributor. READ MORE

4. 2. Chemical modification of cellulose-new possibilities of some classical routes

   Author : Merima Hasani; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Cellulose esters; Cellulose characterization; Cellulose ethers; Cationization; Cellulose nanocrystals; Crosslinking of cellulose;

   Abstract : Owning to its unique structure, along with the inexhaustible renewability, cellulose has been a subject of scientific and commercial interest for over 150 years. However, given attractive structural properties, such as stiffness, hydrophilicity, stereoregularity, potential for chemical modifications and ability to form superstructures, utilization of this biopolymer is far below its potential. READ MORE

5. 3. Improved Usage of Wood Raw Material through Modification of the Kraft Process

   Author : Daniel Tavast; Elisabet Brännvall; Mikael Lindström; Martin Lawoko; Kerstin Forsberg; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; kraft process; impregnation; xylan; spruce; Chemical Engineering; Kemiteknik;

   Abstract :    The kraft process is a complex system with many variables, and though the process is fairly well understood, there is still much we do not know.    This thesis examines some aspects of the kraft process that could prove to be of interest for the pulp and paper industry, specifically, the impact of wood chip impregnation and of the chemical structure of xylan on spruce kraft pulp. READ MORE

6. 4. 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

7. 5. Chemical Modification of Electrospun Cellulose Nanofibers

   Author : Johannes Thunberg; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cellulose Dissolution; Ionic liquid; Polypyrrole; Zeolitic Imidazolate Framework; Nanocellulose; Electrospinning; Cellulose; Metal-organic Framework;

   Abstract : The forest industry is a large part of the Swedish economy and the export of pulp, paper and wood products constitutes 11% of the total Swedish export of goods. The main product of a pulp mill is purified cellulose, which has many great properties like biodegradability and non-toxicity. READ MORE