Wood — the building block of all Domtar products — is composed of cellulose, hemicellulose and lignin. Cellulose and hemicellulose can be converted into cellulosic sugars. In our ongoing quest to find innovative ways to use every part of every tree we harvest, our R&D teams are looking for ways to turn those cellulosic sugars into a wide range of biomaterials and biochemicals.
“We are already using wood — and more specifically, cellulose — as a source for paper and other products. Wood is also a reliable source of sugars,” says Dr. Naren Narendranath, Domtar’s director of BioMaterials Research. “This makes it a good feedstock for biofuels, biochemicals and other sugar-based biomaterials.”
Cellulosic Sugars in Our Trees
The idea of converting cellulosic sugars into biofuels and biochemicals isn’t new. Companies have been doing it for years using corn stover (material left after harvesting corn), wheat straw and other lignocellulosic biomass feedstocks. However, they have struggled to find an efficient and cost-effective way of pretreating or breaking down the raw materials and separating the cellulose, hemicellulose and lignin prior to conversion into cellulosic sugars.
“In a pulp and paper mill, we already have that part figured out, and our industry has been doing it for more than 150 years,” says Narendranath. “The digester is where all the pretreatment happens, and we don’t have to purchase or install any expensive new equipment or chemicals to break down the wood chips. The pretreatment is already complete and produces a clean cellulose stream — what we call pulp.”
The next step is to treat the pulp with enzymes that break down the cellulose into glucose and the hemicellulose into xylose (collectively termed cellulosic sugars), which can be used for producing biomaterials. Narendranath says this is where the research really becomes exciting.
“We have been getting 95 to 99 percent conversion of cellulose to glucose with our wood pulp. With corn stover, for example, the best you can get is 75 to 80 percent conversion,” he says. “This has been really encouraging for us. Plus, our sugar is cleaner; easier to ferment into alcohols, such as ethanol, that can be used as a biofuel; and easier to process into end products compared to sugar from other lignocellulosic feedstocks.”
Cellulosic Sugars Are Game Changers
Breaking into highly competitive markets can be extremely difficult, if not next to impossible. “The incumbents are very smart, well-financed and armed with technology and a supply chain that can be more than a century old. Most of all, they do not want to give up market share,” says Mark DeAndrea, vice president and business unit leader of Domtar’s BioMaterials Innovation team.
The good news is that our success in this field is not based on disrupting an incumbent. “Our strategy is to work with incumbents to develop proprietary solutions and to help solve some of their biggest problems,” says Narendranath.
Cellulosic sugars can be made into a wide range of biomaterials that can help our partners reduce their use of fossil fuels and minimize their carbon footprints. Some of the products we’re developing include:
more at: https://newsroom.domtar.com/cellulosic-sugars/