The effect of ionic strength and pH on the dewatering rate of cellulose nanofibril dispersionsShow others and affiliations
2022 (English)In: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Vol. 29, no 14, p. 7649-7662Article in journal (Refereed) Published
Abstract [en]
Cellulose nanofibrils, CNFs, show great potential in many application areas. One main aspect limiting the industrial use is the slow and energy demanding dewatering of CNF suspensions. Here we investigate the dewatering with a piston press process. Three different CNF grades were dewatered to solid contents between approx. 20 and 30%. The CNF grades varied in charge density (30, 106 and 604 µmol/g) and fibrillation degree. The chemical conditions were varied by changing salt concentration (NaCl) and pH and the dewatering rates were compared before and after these changes. For the original suspensions, a higher charge provides slower dewatering with the substantially slowest dewatering for the highest charged CNFs. However, by changing the conditions it dewatered as fast as the two lower charged CNFs, even though the salt/acid additions also improved the dewatering rate for these two CNFs. Finally, by tuning the conditions, fast dewatering could be obtained with only minor effect on film properties (strength and oxygen barrier) produced from redispersed dispersion. However, dewatering gives some reduction in viscosity of the redispersed dispersions. This may be a disadvantage if the CNF application is as e.g. rheology modifier or emulsion stabilizer. Graphical abstract: [Figure not available: see fulltext.].
Place, publisher, year, edition, pages
Springer Science and Business Media B.V. , 2022. Vol. 29, no 14, p. 7649-7662
Keywords [en]
Cellulose nanofibrils, Dewatering, Nanocelluloses, Redispersion, Rheology, Dispersions, Elasticity, Emulsification, Ionic strength, Nanofibers, Sodium chloride, Application area, Condition, Effect of ionic strength, Energy, Industrial use, Nano-cellulose, Press process, Redispersions, Solids content, Nanocellulose
National Category
Materials Engineering
Identifiers
URN: urn:nbn:se:ri:diva-59856DOI: 10.1007/s10570-022-04719-yScopus ID: 2-s2.0-85134482558OAI: oai:DiVA.org:ri-59856DiVA, id: diva2:1685234
Note
Correspondence Address: Syverud, K.; RISE PFI, Høgskoleringen 6b, Norway; email: kristin.syverud@rise-pfi.no; Funding details: Norges Forskningsråd, 245300, 274975; Funding text 1: Open access funding provided by RISE Research Institutes of Sweden. This work was a part of the project NanoVisc: “Development of high-performance viscosifiers and texture ingredients for industrial applications based on Cellulose Nanofibrils (CNF)” financed by the Research Council of Norway through the Nano2021 programme (Grant No. 245300), and the companies Borregaard, Mercer, and Stora Enso. Part of the work has also been funded through the project NanoPlasma: Nanofibril production using plasma (Grant No. 274975) and from RISE.
2022-08-022022-08-022023-12-06Bibliographically approved