Search for dissertations about: "Olena Sevastyanova"

Showing result 1 - 5 of 7 swedish dissertations containing the words Olena Sevastyanova.

  2. 1. Oxidizable structures in kraft pulps : chemical properties and bleaching response

    Author : Olena Sevastyanova; KTH; []
    Keywords : ;

    Abstract : .... READ MORE

  4. 2. On the importance of oxidizable structures in bleached kraft pulps

    Author : Olena Sevastyanova; Göran Gellerstedt; Colodette Jorge; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bleached pulps; betula; eucalyptus; 5-formyl-2furancarboxylic acid; 2-furancarboxylic acid; hexenuronic acid; kappa number; kraft pulps; oxidation equivalents; Cellulose and paper engineering; Cellulosa- och pappersteknik;

    Abstract : After cooking, kraft pulps always contain not only residual lignin but also significant amounts of hexenuronic acid and other non-lignin structures oxidizable by permanganate under the standard kappa number determination conditions. These here referred to as false lignin. READ MORE

  5. 3. Pulp strength enhancement by oxygen delignification

    Author : Claudia Esteves; Elisabet Brännvall; Olena Sevastyanova; Sören Östlund; Christine Chirat; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fiber charge; morphology; oxygen delignification; swellability; tensile properties; dragegenskaper; fiberladdningar; morfologi; svällningsförmåga; syrgasdelignifiering; Chemical Engineering; Kemiteknik;

    Abstract : Oxygen delignification is widely used in the pulp and paper industry as a part of delignification process between the kraft cook and bleaching. However, its potential has not been fully utilized. READ MORE

  6. 4. Protected Lignin Biorefining: Fundamental Insights on Lignin Reactivity

    Author : Maria Karlsson; Martin Lawoko; Åsa Emmer; Olena Sevastyanova; John Ralph; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Sustainability; lignin; biorefinery; cyclic organosolv extraction; preserved structure; NMR; MALDI-TOF MS; Hållbarhet; lignin; bioraffinaderi; cyklisk organosolv extraktion; bevarad struktur; NMR; MALDI-TOF MS; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Abstract : The potential to utilize lignin, which constitutes as much as 15-30% of the biomass, needs further evaluation. In the transition towards a bioeconomy, lignin has the potential to replace fossil-based phenols. Attempts to valorize the available technical lignins are ongoing; however, that lignin suffers from molecular heterogeneity. READ MORE

  7. 5. On the Process Development of an ECF Light Bleaching Sequence for the Production of High Quality Softwood Kraft Pulp and Low AOX Formation

    Author : Sara Starrsjö; Juha Fiskari; Mikael Lindström; Olena Sevastyanova; Maria Boman; Peter Sandström; Mittuniversitetet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Chemical Engineering; Natural Science; Chemical Pulping; Softwood; Kraft Pulp; Bleaching; ECF light bleaching; Chlorine Dioxide; AOX formation; Delignification; Bleachability;

    Abstract : The aim of this work is to contribute to the process development of the ECF light bleaching sequence Q(OP)D(PO) by providing a better understanding of the bleaching of softwood kraft pulp. There are few published studies on this type of sequence, and more knowledge is needed on how to reduce environmental impact, improve cost-effectiveness and ensure a high pulp quality. READ MORE