Sökning: "residual lignin"

Visar resultat 1 - 5 av 30 avhandlingar innehållade orden residual lignin.

  1. 1. On the structure of residual lignin in kraft pulping

    Författare :Andrea Majtnerová; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; biphenyl structures; kappa number; kraft pulping; phenols; radical coupling; residual delignificaiton; residual lignin; softwood; Cellulose and paper engineering; Cellulosa- och pappersteknik;

    Sammanfattning : .... LÄS MER

  3. 2. Some factors affecting the amount of residual phase lignin during kraft pulping

    Författare :Mikael E. Lindström; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Deligniflcation; Residual phase lignin; Hydrogensulfide ion; Hydroxide ion; Polysulfides; Ionic strength; Temperature; Lignin; Kraftpulping; Selectivity; viscosity; Kappa number; chemical degradation; Disproportionation; Cellulose and paper engineering; Cellulosa- och pappersteknik;

    Sammanfattning : The amount of lignin which needs to be removed according to the slow residual delignification phase in kraft pulping, i e residual phase lignin, has been studied as a function of the process conditions. The variebles studied were the concentrations of hydroxide ions, hydrogensulfide ions, sodium ions (ionic strength) and temperature. LÄS MER

  4. 3. On the bleachability of alkaline pulps. The influence of residual lignin structure

    Författare :Waleed Wafa Al-Dajani; KTH; []
    Nyckelord :B-O-4; bleachability; hexenuronic acid; hydrogen peroxide; hydrosulfide ion; hydroxyl ion; ionic strength; residual lignin.;

    Sammanfattning : .... LÄS MER

  5. 4. Potential of Organosolv Lignin Nanoparticles as a Sustainable Flotation Reagent : Towards a Low-Carbon Footprint Mining Industry

    Författare :Katerina Hruzova; Ulrika Rova; Saija Luukkanen; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Organosolv lignin particles; Nanoparticles; Flotation reagent; Copper recovery; Biokemisk processteknik; Biochemical Process Engineering;

    Sammanfattning : The green transition is driving a steep increase in the demand for minerals, which has put the focus on more responsible and sustainable mining practices as there is a growing pressure on mining operations to minimise their environmental footprint, mitigate risks in neighbouring communities, and decrease the consumption of natural resources. In 2022, mineral froth flotation was used to recover 18 million tonnes of copper from copper ore, accounting for 80% of total copper mine output. LÄS MER

  7. 5. The effects of oxygen on the degradation of lignin model compounds and residual lignin

    Författare :Eva Johansson; KTH; []
    Nyckelord :;

    Sammanfattning : The aim of this work was to achieve a further understandingof the reactivity of lignin structures and residual ligninduring oxygen bleaching. The kinetics of lignin model compoundssuch as diguaiacyl stilbene, propylguaiacol,dipropylbiguaiacol, enol ether and β-aryl ether structuresunder oxygen bleaching conditions have been studied. LÄS MER