Search
Use the search bar or filters below to find any TAPPI product or publication.
Filters
Content Type
Publications
Level of Knowledge
Committees
Collections
Journal articles
Magazine articles
A new method of studying the fundamental mechanisms involved in pigment liberation from recycle papers, TAPPI Journal October 2022
ABSTRACT: Deinking flotation is the most efficient and widely used method of removing ink particles from printed papers to improve the recyclability. A prerequisite for successful deinking flotation is detachment of pigments from paper fibers, a subprocess known as liberation. The degree of liberation is usually determined via hyperwashing tests, which are costly and time consuming. Furthermore, they provide no information on the fundamental mechanisms controlling liberation. In the present work, we developed a new method in which ?-potentials of the particles in a pulp are measured and analyzed. If pigments are not liberated from paper fibers, a frequency distribution plot gives a single peak, while two peaks appear when they are liberated. One can readily determine the degrees of liberation from the peak positions and peak heights. In addition, the ?-potential data can be used to construct disjoining pressure isotherms using the DLVO theory that are useful to better understand the fundamental mechanisms involved and the roles of different reagents used to improve pigment liberation.
Journal articles
Magazine articles
Effects of orders of addition in nanocellulose•cationic starch• colloidal silica systems for papermaking, TAPPI Journal October 2022
ABSTRACT: Two orders of addition were compared when preparing paper handsheets from recycled copy paper furnish in combination with nanofibrillated cellulose (NFC), cationic starch, colloidal silica, and cationic retention aid (cPAM; cationic polyacrylamide). Faster dewatering and higher fine-particle retention were obtained at equal optimized dosages of additives when the colloidal silica was added last, after addition of the cPAM. The same order of addition also provided a higher gain in the paper’s tensile strength. However, higher paper stiffness was achieved when the colloidal silica was instead added to the NFC, after its pretreatment with cationic starch. Results were consistent with the principle that papermaking additives added shortly before sheetforming tend to have the largest effects on drainage and retention. The results also demonstrated a sensitivity to the relative dosages of positively and negatively charged additives.
Journal articles
Performance of High Vacuum Dewatering Elements in the Formin
Performance of High Vacuum Dewatering Elements in the Forming Section, 1993 Engineering Conference Proceedings
Journal articles
Cold Blow Batch Cooking Plus Medium Consistency Oxygen: Heat
Cold Blow Batch Cooking Plus Medium Consistency Oxygen: Heat Exchanger Placement, 1993 Engineering Conference Proceedings
Journal articles
Hydrodynamics of the Forming Section: The Origin of Nonunifo
Hydrodynamics of the Forming Section: The Origin of Nonuniform Fiber Orientation, 1994 Engineering Conference Proceedings
Journal articles
Machine Vision Applications Using Binary and Grayscale Morph
Machine Vision Applications Using Binary and Grayscale Morphology, 1994 Engineering Conference Proceedings
Journal articles
Model to Predict the Precipitation of Burkeite in the Multip
Model to Predict the Precipitation of Burkeite in the Multiple Effect Evaporator and Techniques for Controlling Scaling, 1995 Engineering Conference Proceedings
Journal articles
Liquor-To-Liquor Differences in Combustion and Gasification
Liquor-To-Liquor Differences in Combustion and Gasification Processes: Nitrogen Oxide Formation Tendency, 1995 Engineering Conference Proceedings
Journal articles
Thermal stability of paper fillers: a strong case for a low temperature paper ashing, TAPPI JOURNAL, March 1996, Vol. 79(3)
Thermal stability of paper fillers: a strong case for a low temperature paper ashing, TAPPI JOURNAL, March 1996, Vol. 79(3)
Journal articles
Effect of basestock formation on paper coating, TAPPI JOURNAL, May 1996, Vol. 79(5)
Effect of basestock formation on paper coating, TAPPI JOURNAL, May 1996, Vol. 79(5)