- Written by Anna Strom
If you ask Bio4Energy researchers at the Luleå University of Technology (LTU) the answer is “hopefully, yes”. Tomorrow they are taking a symbolic but decisive step towards reaching their goal. Martha Herrera of the Wood and Bionanocomposites’ division will be taking the stage at LTU to present the group’s finding contained in three scientific articles and one licentiate thesis on Nanostructured Materials Isolated from Bio-Residues, and their Characterisation.
In her thesis, Herrera outlines her team’s efforts at characterising a certain type of nanocomponents, or ‘nanowhiskers’, from two types of residual streams from biorefinery production based on woody raw materials. While one was a by-product of ethanol production by the Swedish clean technology firm SEKAB, the other consisted of reject cellulose from making specialty cellulose at Domsjö Fabriker, at Örnsköldsvik, Sweden, Herrera said.
“We have demonstrated that they can be successfully extracted from bio-residues”, Herrera said with reference to the two nanowhisker suspensions—reject cellulose and bioethanol residue, respectively—which characteristics are accounted for in the thesis. She believed that this was the first time nanowhiskers had been extracted from an industrial waste stream based on woody raw materials. Previously, this kind of process had mainly been applied to bio-residues from agriculture, such as banana leaves, Herrera said.
Nanocomposites to enhance packaging or purify air
The LTU Wood and Bionanocomposites’ research group was hoping, in a third step after more laboratory work, to use the results in applications designed to separate gases from each other or to purify air, Herrera said. However, the team was not targeting any specific gas at this stage. For air purification, the technology might be used to make thin films of nanocomposites for filtering out or capturing bacteria or undesirable particles, such as particulate matter from car exhaust. A further line of use could be as a containment, or "barrier", gas in packaging, “to protect food from different gases… or avoid material from getting damaged”, according to Herrera.
Advantages of replacing current solid materials such as plastics or aluminum in certain types of packaging (while adding fewer layers and thus, less weight) with cellulose-based nanocomposites could consist in the removal of a number of energy-intensive steps and less material loss in the production process.
Said Herrera: “Generally, you have to reduce size; there is cleaning, bleaching, hydrolysis. This involves losing a lot of materials. These are not lost in the residues that we are using. At the end we are saving steps and recovering more material. At the end it’s a win-win situation. They get their ethanol, I get my residues. There is no residue” in the form of waste from the process, she said, with a nod to the industrial firms having provided residual materials for the researchers to study.
Soon a licentiate engineer, the current Master of science holder expects to run further trials next year on the two kinds of nanowhiskers at Monash University of Australia. The university had specialty equipment needed to take the project forward, Herrera said. Her research group at LTU, led by professor Kristiina Oksman of Bio4Energy, hoped to have results to underpin one or more practical use application for the nanowhiskers within two years.
But first, Herrera looked forward to pass the test at her more imminent licentiate presentation at LTU, she said. This kicks off at 1 p.m., 4 December 2012, in room E632 at LTU in northern Sweden.