Use of nanofibrillated cellulose in the modification of ultrafiltration membranes
Obi, Chike Hilary (2019)
Diplomityö
2019
School of Engineering Science, Kemiantekniikka
Kaikki oikeudet pidätetään.
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi-fe2019120245264
https://urn.fi/URN:NBN:fi-fe2019120245264
Tiivistelmä
Utilization of biomass as a more sustainable and environmentally friendly substitute to fossil raw material has been proven to be beneficial in several industries. Cellulose is a linear long chain polysaccharide that can easily be converted into nanocellulose using mechanical or chemical or biological treatment. Known characteristics of nanocellulose, for example, high chemical resistance, surface area, and aspect ratio, makes nanocellulose more desirable than the original cellulose in certain applications.
This study aims at utilizing mechanically produced nanocellulose from DES (deep eutectic solvent) treated pulp to modify commercial ultrafiltration membranes, in order to improve the rejection while permeability is maintained. For this purpose, RC70PP, UH004P, ETNA 10PP and UFX10 membranes were modified with nanocellulose. The results from this study showed that modification of the RC70PP and UH004P was successful and both gave an improved rejection while permeability was not affected. However, both the ETNA 10P and UFX10 membranes showed no improvement after the modification with nanocellulose. In case of surface modification of RC70PP membrane, modified membranes with less negative surface charge compared to native membrane were obtained. In the best-case scenario, using 6.58 g/m2 of nanocellulose from bleached DES treated softwood pulp in modification of the RC70PP membrane demonstrated the most improvement in rejection up to 90% and the permeability was maintained.
This study aims at utilizing mechanically produced nanocellulose from DES (deep eutectic solvent) treated pulp to modify commercial ultrafiltration membranes, in order to improve the rejection while permeability is maintained. For this purpose, RC70PP, UH004P, ETNA 10PP and UFX10 membranes were modified with nanocellulose. The results from this study showed that modification of the RC70PP and UH004P was successful and both gave an improved rejection while permeability was not affected. However, both the ETNA 10P and UFX10 membranes showed no improvement after the modification with nanocellulose. In case of surface modification of RC70PP membrane, modified membranes with less negative surface charge compared to native membrane were obtained. In the best-case scenario, using 6.58 g/m2 of nanocellulose from bleached DES treated softwood pulp in modification of the RC70PP membrane demonstrated the most improvement in rejection up to 90% and the permeability was maintained.