Search for dissertations about: "Sodium dithionite"

Showing result 1 - 5 of 8 swedish dissertations containing the words Sodium dithionite.

  2. 1. Influence of acid hydrogen peroxide treatment on refining energy and TMP properties

    Author : Karin Walter; Per Engstrand; Magnus Paulsson; Lennart Salmén; Mittuniversitetet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TMP; Black Spruce; Energy reduction; Hydrogen peroxide; Ferrous sulphate; Refining; Inter-stage treatment; Pulp and paper properties; Fenton´s reagent; Bleaching; Sodium dithionite; Brightness; Metals; Fibre dimensions; Cross-sectional dimensions; Chemical composition; Cellulose and paper engineering; Cellulosa- och pappersteknik;

    Abstract : The potential of using acid hydrogen peroxide under Fenton conditions to lower the electrical energy consumed during the production of Black spruce (Picea mariana) thermomechanical pulp (TMP) was investigated. The chemical system, which consisted of ferrous sulphate, hydrogen peroxide and optionally an enhancer (3,4-dimethoxybenzyl alcohol, ethylenediaminetetraacetic acid or oxalic acid/sodium oxalate), was evaluated as an inter-stage treatment where the primary refiner was used as a mixer. READ MORE

  4. 2. Pretreatment and Enzymatic Treatment of Spruce : A functional designed wood components separation for a future biorefinery

    Author : Yan Wang; Gunnar Henriksson; Mikael E. Lindström; Hans Theliander; Martin Lawoko; Adriaan van Heiningen; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; kraft cooking; extended impregnation; enzymes; chemo-enzymatic separation process; peeling reaction; sodium borohydride; polysulfide; anthraquinone; sodium dithionite; mild steam explosion; biorefinery.; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Abstract : The three main components of wood, namely, cellulose, hemicellulose, and lignin, can be used in various areas. However, since lignin covalently crosslinks with wood polysaccharides creating networks that is an obstacle for extraction, direct extraction of different wood components in high yield is not an easy matter. READ MORE

  5. 3. Biorefining of lignocellulose : Detoxification of inhibitory hydrolysates and potential utilization of residual streams for production of enzymes

    Author : Adnan Cavka; Leif J. Jönsson; John N. Saddler; Umeå universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : Lignocellulosic biomass is a renewable resource that can be utilized for the production of biofuels, chemicals, and bio-based materials. Biochemical conversion of lignocellulose to advanced biofuels, such as cellulosic ethanol, is generally performed through microbial fermentation of sugars generated by thermochemical pretreatment of the biomass followed by an enzymatic hydrolysis of the cellulose. READ MORE

  6. 4. Biochemical conversion of biomass : hydrothermal pretreatment, by-product formation, conditioning, enzymatic saccharification, and fermentability

    Author : Dimitrios Ilanidis; Leif J. Jönsson; Carlos Martin; Björn Alriksson; Eulogio Castro; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; lignocellulosic biomass; hydrothermal pretreatment; enzymatic digestibility; ethanolic fermentation; microbial inhibitors; conditioning;

    Abstract : Lignocellulosic residues have great potential as feedstocks for production of bio-based chemicals and fuels. One of the main routes is biochemical conversion, which typically includes pretreatment, enzymatic saccharification, microbial fermentation of sugars, and valorization of hydrolysis lignin. READ MORE

  7. 5. The influence of high temperature on the discoloration and degradation of carbohydrates and on hydrogen peroxide bleaching of spruce TMP

    Author : Louise Logenius; Hans Höglund; Roland Agnemo; Mittuniversitetet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Temperature; metal ions; cellulose; glucuronic acid; UV-Vis spectroscopy; spruce; TMP; hydrogen peroxide bleaching; spectroscopy; optical properties; Chemical engineering; Kemiteknik;

    Abstract : When processing wood to obtain pulp, the fibers are subjected to high temperatureat moisture levels and to the influence of metal ions. Many process developmentshave resulted in utilization of higher temperatures that induce chemical reactionsin the wood fibers. This thesis deals with some aspects of using high temperaturesin pulping processes. READ MORE