As the most abundant polymer in the natural world, cellulose can be derived from many sources. Today, most cellulose is derived from wood pulp; however, with the reduction of deforestation being a top priority in reducing greenhouse gas emissions, identifying alternative sustainable sources has become of utmost importance to the majority of global organizations whose companies depend on this base compound.
The main categories of cellulose sources are wood, plants, bacteria, algae, and one species of sea animal. With wood being obviously unsustainable, the remaining categories and resulting sources are:
- Plant – hops, hemp, flax, jute, kenaf, ramie, sisal, bamboo, cotton
- Algae – green, gray, red, and yellow-green; most research using green
- Bacteria – most studied species is Gluconacetobacter xylinus
- Animal – Tunicates, family of sea animals known as Ascidiacea; only animals known to produce cellulose
At Cellulogyx, we took a deep dive into all of these categorical sources for cellulose. Ultimately, significant analysis demonstrated that plant-derived cellulose is both the most sustainable and most scalable. Upon a determination of the plant category, a review of tensile strength, Young’s modulus, microfibril angle, crystallinity index, cellulose percentage, yield per hectare/acre, content of mineral substances, morphology, and versatility inability to grow in both moderate and boreal climates was performed across the various options within the category.
In consideration of this being a blog post and not a research paper, we will simply skip to the results: ultimately, fibrous hemp and hops vines (both members of the cannabaceae family of plants) had much higher overall scores when scored across all categories (results available upon request). Another interesting benefit of these cellulose sources are their potential elimination of Kraft pulping – the pulping process alluded to earlier when “cooking” the wood for cellulose extraction and a large contributor to GHG emissions within the paper and pulp industries. With hops and hemp, using only oxygen delignification, autohydrolysis and some amount of bleaching may be possible; reducing chemical usage, reducing GHG emissions, and increasing biodegradability.
Ok, so hops and hemp are better for the environment – where do they functionally excel relative to wood-derived cellulose?
- Low Density / Light Weight
- Superior Mechanical Strength
- Excellent Stiffness
- Chemical Inertness
- Low Coefficient of Thermal Expansion
- Dimensional Stability
- Ability to Modify its Surface Chemistry