Thesis defence in the University of Oulu

Doctoral Candidate

Master of Science in Technology Jonna Ojala

Faculty and research unit

University of Oulu Graduate School, Faculty of Technology, Fibre and Particle Engineering research unit

Field of study

Process Engineering

Date and time of the thesis defence

10.5.2019 12:00

Place of the thesis defence

Linnanmaa, hall TA105 (Arina Hall)

Topic of the dissertation

Functionalized cellulose nanoparticles in the stabilization of oil-in-water emulsions. Bio-based approach to chemical oil spill response.

Opponent

Research Professor Tekla Tammelin, VTT Technical Research Centre of Finland Ltd.

Custos

Associate Professor Henrikki Liimatainen, University of Oulu

Arctic oil-spill response using wood nanocellulose

The climate warming will slowly melt the permanent ice cover in Arctic, opening up new sea transport routes and enabling oil drilling in the Arctic. This clearly increases the risk of oil accidents, which can be very destructive to the unique nature of the Arctic. Many commercial oil spill chemicals are harmful to the ecosystem and are therefore limited in their use. The aim of this thesis was to investigate the possibilities of developing a new type of bio-based and non-toxic oil spill response chemical from wood pulp.

The nanocellulose is referring to nano-structured cellulose. In this study, the surface properties of wood nanocellulose were modified by various chemical pretreatments so that it would more readily penetrate and adhere to the oil droplet surface. As a result of the work, it can be stated that the cellulose nanoparticles work well in a diesel-water-emulsion to prevent the oil droplets in the emulsion from coalescing. The nanoparticles cover the surface of the oil droplet, stabilizing the droplet in small size, which facilitates the natural biodegradation of bacteria by the sea.

Nanocellulose is renewable and biodegradable raw material having many superior properties such as strength, lightness, transparency and good thermal insulation. Therefore, nanocellulose can be used almost unlimitedly for various applications. In addition, cellulose is abundantly available, for example, from industrial waste streams or agricultural waste. That makes its production more cost-effective, bringing added value to waste while supporting the circular economy ideology.

Dissertation

Last updated: 6.5.2019