Sökning: "molecular weight of lignin"

Visar resultat 1 - 5 av 45 avhandlingar innehållade orden molecular weight of lignin.

1. 1. Towards molecular weight-dependent uses of kraft lignin

   Författare :Ayumu Tagami; Mikael Lindström; Olena Sevastyanova; Anna Wistrand; Stefan Backa; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; kraft lignin; successive solvent fractionation; molecular weight; structural analysis; thermal stability; heat capacity; antioxidant activity; methylene blue sorption; tunicate cellulose nanofiber-starch lignin composites films; film properties; Fiber- och polymervetenskap; Fibre and Polymer Science;

   Sammanfattning : There is growing demand for a more efficient use of polymers that originate from renewable feedstocks due to the depleting supply of fossil fuels, based on economic and environmental reasons. As a result, lignin has attracted renewed interest as a resource for various bioproducts. LÄS MER

3. 2. Precipitation of Kraft Lignin: Yield and Equilibrium

   Författare :Weizhen Zhu; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; lignin precipitation; molecular weight of lignin; 1H and 13C NMR spectra of lignin; black liquor; Poisson-Boltzmann cell model; LignoBoost process;

   Sammanfattning : Kraft pulping is the dominant pulping process used in the world today. The material efficiency in modern kraft pulp mills is, however, only 40−55% and the final product consists mainly of cellulose. Recently, a novel process called “LignoBoost” has been introduced to separate lignin from kraft black liquor. LÄS MER

4. 3. Towards bacterial valorization of low molecular weight lignin

   Författare :Krithika Ravi; Avdelningen för kemiteknik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Pseudomonas putida; Microbacterium sp.; Guaiacol; Syringate; Kraft lignin; Bioconversion; Biorefineries;

   Sammanfattning : Lignin is one of the major constituents in lignocellulosic biomass and is the mostabundant source of renewable aromatics on terrestrial ecosystems. The workcarried out in this thesis concerns bacterial conversion of low molecular weightlignin. LÄS MER

5. 4. Equilibrium of lignin precipitation: The effects of pH, temperature, ion strength and wood origins

   Författare :Weizhen Zhu; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; black liquor; 1H and 13C NMR spectra of lignin; carbohydrate analysis; molecular weight of lignin; LignoBoost process; lignin precipitation;

   Sammanfattning : The kraft process is the predominant method for producing pulp in Scandinavia. However, the material efficiency in modern kraft pulp mills for pulp production is only 40−55% and the final product consists mainly of cellulose. A novel process called “LignoBoost” has been introduced recently for extracting lignin from alkaline black liquor. LÄS MER

7. 5. On the Course of Kraft Cooking - The impact of ionic strength

   Författare :Binh Dang; Chalmers tekniska högskola; []
   Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; molecular weight distribution.; hexenuronic acids; carbohydrate removal; delignification; sodium ion concentration; lignin; ionic strength; xylan; flow-through kraft cooking; kinetics;

   Sammanfattning : Kraft pulping is the dominant process currently used to produce chemical pulps, and has been applied for more than 130 years. A large number of studies have been conducted to gain a better understanding of the delignification kinetics as well as the reactions of the wood components being dissolved during the cooking process. LÄS MER