Sökning: "Anette Heijnesson Hultén"

Hittade 3 avhandlingar innehållade orden Anette Heijnesson Hultén.

  1. 1. Kraft Pulp Fibre Surfaces. Chemical Composition and Effect on Pulp Bleachability

    Författare :Anette Heijnesson Hultén; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ray cells; carbohydrates; Kraft pulps; enzymes; lignin; fibre surfaces; metal ions; bleachability;

    Sammanfattning : The work presented in this thesis concerns studies of kraft fibre surfaces in respect of chemical composition and effect on pulp bleachability. Kraft fibre surfaces were studied by mechanical peeling using a disintegrator operated at 20.000-200.000 revolutions and a pulp consistency of 3% or 4. LÄS MER

  3. 2. Studies of surface material from unbleached kraft fibres

    Författare :Anette Heijnesson Hultén; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fines; lignin; surface structure; kraft pulp; metal ions;

    Sammanfattning : .... LÄS MER

  4. 3. Fenton Pre-treatment of a Birch Kraft Pulp for MFC preparation

    Författare :Pia Hellström; Helena Håkansson; Anette Heijnesson Hultén; Magnus Paulsson; Monica Ek; Karlstads universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Microfibrillated cellulose; Fenton chemistry; carbonyl groups; surface charge; total charge; Enzymatic hydrolysis; Tensile strength; z-directional strength; Chemical Engineering; Kemiteknik;

    Sammanfattning : The potential to use acidic hydrogen peroxide in the presence of ferrous ions (Fenton’s reagent) as a pre-treatment when producing microfibrillar cellulose (MFC) from a fully bleached birch (Betula verucosa) kraft pulp was investigated and the properties of the produced MFC was compared to the properties of a MFC produced with enzymatic pre-treatment with a monocomponent endoglucanase (FiberCare® R). The mechanical treatment to MFC was performed in a laboratory colloid mill or in a pilot high-pressure homogeniser and the pre-treated pulps as well as the produced MFCs were chemically and morphologically characterised. LÄS MER