• Login
    View Item 
    •   SMARTech Home
    • Georgia Tech Theses and Dissertations
    • Georgia Tech Theses and Dissertations
    • View Item
    •   SMARTech Home
    • Georgia Tech Theses and Dissertations
    • Georgia Tech Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Enhanced contaminants removal for paper recycling by adsorption deinking and new flotation methods

    Thumbnail
    View/Open
    DU-DISSERTATION-2017.pdf (6.279Mb)
    Date
    2017-07-27
    Author
    Du, Xiaotang
    Metadata
    Show full item record
    Abstract
    The recent progress and increasing popularity in digital printing technology created new challenges in recycled paper quality and recycling process runnability due to the sub-micron size, strongly negative charge, and hydrophilic nature of ink particles. As a result, hydrophilic inks are not compatible with state of art flotation deinking that relies on surface hydrophobicity. The new hydrophilic ink would stay in the recirculating water, redeposit into the fiber lumen and decrease the fiber brightness. Adsorption deinking by chitosan and advanced flotation methods were studied for removal of hydrophilic inks from cellulose fiber and water. The ink behavior during pulping was investigated and it was shown that 53% of total ink stays in water phase, 31% redeposits into fiber lumen during pulping and 16% remains attached with cellulose fiber. Thus, redeposited ink is a major concern to control cellulose fiber quality and chitosan can adsorb ink particles during pulping which results in 5 points increase in ISO Brightness besides 90% water saving and 20% energy saving. For free inks in water, two different advanced flotation techniques were studied, including electroflotation and oily-bubble flotation. Firstly, electric treatment agglomerates ink particle from 60nm to 700nm and removes 25% ink through electroflotation mechanism. Secondly, the adsorption of ink particles on silicone oil/water interface was proved by dynamic interfacial tension, and the silicone oil coated bubble flotation shows advantages in both thermodynamics and kinetics. The usefulness of an oil layer outside air bubbles in reducing adsorption energy barrier was demonstrated by a model system and the root cause for the decrease in energy barrier is van der Waals interactions.
    URI
    http://hdl.handle.net/1853/60169
    Collections
    • School of Chemical and Biomolecular Engineering Theses and Dissertations [1438]
    • Georgia Tech Theses and Dissertations [22398]

    Browse

    All of SMARTechCommunities & CollectionsDatesAuthorsTitlesSubjectsTypesThis CollectionDatesAuthorsTitlesSubjectsTypes

    My SMARTech

    Login

    Statistics

    View Usage StatisticsView Google Analytics Statistics
    • About
    • Terms of Use
    • Contact Us
    • Emergency Information
    • Legal & Privacy Information
    • Accessibility
    • Accountability
    • Accreditation
    • Employment
    • Login
    Georgia Tech

    © Georgia Institute of Technology

    • About
    • Terms of Use
    • Contact Us
    • Emergency Information
    • Legal & Privacy Information
    • Accessibility
    • Accountability
    • Accreditation
    • Employment
    • Login
    Georgia Tech

    © Georgia Institute of Technology