Ultrasonic Production of Nano-Structured Cellulose
Nanocellulose, a remarkable high-performance additive, has gained prominence for its versatile applications as a rheology modifier, reinforcing agent, and key component in various advanced materials. These nano-structured fibrils, derived from any cellulose-containing source, can be efficiently isolated through high-power ultrasonic homogenization and milling. This process, known as sonication, significantly enhances fibrillation, resulting in a higher yield of nanocellulose and producing finer, thinner fibers. Ultrasonic technology surpasses conventional manufacturing methods, thanks to its ability to generate extreme cavitational high shear forces, making it an exceptional tool for nanocellulose production.
Ultrasonic Manufacture of Nanocellulose
High power ultrasonics contributes to the extraction and isolation of micro- and nano-cellulose from various sources of cellulosic materials such as wood, lignocellulosic fibers (pulp fibers), and cellulose containing residues.
To release the plant fibres from the source material, ultrasonic grinding and homogenization is a powerful and reliable method, that allows to process very large volumes. The pulp is fed into an inline sonoreactor, where ultrasonic high-shear forces break the cell structure of the biomass so that the fibrillous matter becomes available.

Nanocellulose slurries are reliably dispersed using ultrasonication. The picture shows the high-performance sonicator UIP2000hdT in a batch setup.
[Bittencourt et al. 2008]

TEM image of “Never Dried Cotton” (NDC) submitted to enzymatic hydrolysis and sonicated with Hielscher sonicator UP400S for 20 minutes. [Bittencourt et al. 2008]
Figure 2 below shows a SEM image of a film of viscose, submitted to the enzymatic hydrolysis, followed by sonication with the Hielscher sonicator model UP400S.
[Bittencourt et al. 2008]

SEM image of a film of viscose, submitted to the enzymatic hydrolysis, followed by sonication with UP400S [Bittencourt et al. 2008]
Ultrasonic nanocellulose processing can be also successfully combined with the TEMPO-oxidized fiber treatment. In the TEMPO-process, cellulose nanofibers are produced by an oxidation system using 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO) as catalyst, and sodium bromide (NaBr) and sodium hypochlorite (NaOCl). Research has proven that the oxidation efficiency is significantly improved when the oxidation is conducted under ultrasonic irradiation.
Ultrasonic Dispersion of Nanocellulose
Nanocellulose dispersions demonstrate an extraordinary rheological behaviour due to its high viscosity at low nanocellulose concentrations. This makes nanocellulose a very interesting additive as rheological modifier, stabilizer and gellant for various applications, e.g. in the coating, paper, or food industry. To express its unique properties, nanocellulose must be
Ultrasonic dispersing is the ideal method to obtain fine-size, single-dispersed nanocellulose. As nanocellulose is highly shear-thinning, power ultrasound is the preferrable technology to formulate nanocellulosic suspensions as the coupling of high-power ultrasound into liquids creates extreme shear forces.
Click here to learn more about ultrasonic cavitation in liquids!
After the synthesis of nanocrystalline cellulose, the nanocellulose is often ultrasonically dispersed into a liquid medium, e.g. a non-polar or polar solvent such as dimethylformamide (DMF), to formulate a final product (e.g. nanocomposites, rheological modifier etc.) As CNFs are used as additives in manifold formulations, a reliable dispersing is crucial. Ultrasonication produces stable and uniformly dispersed fibrils.
Ultrasonically Improved Dewatering of Cellulose Nanofibers
Ultrasonically enhanced dewatering of cellulose nanofibers is a cutting-edge technique that significantly improves the efficiency of water removal – making cellulose nanofibers an highly attractive additive for nanopaper production. Nanocellulose fibers, typically requires time-intensive dewatering due to its high water retention capacity. By applying ultrasonic waves, this process is accelerated through the generation of intense cavitational forces, which disrupt the water matrix and facilitate faster, more uniform water expulsion. This not only reduces drying time but also enhances the structural integrity and mechanical properties of the resulting cellulose nanofibers, making it a highly effective method in the production of high-quality nanopapers and other nanomaterials.
Learn more about ultrasonic dewatering of nanopaper!
Industrial Nanocellulose Production using Power Ultrasound
Hielscher Ultrasonics offers a comprehensive range of powerful and reliable ultrasonic solutions, from small lab-scale ultrasonicators to large-scale industrial systems, ideal for the commercial processing of nanocellulose. The key advantage of Hielscher industrial probe-type sonicators lies in their ability to deliver optimal ultrasonic conditions through their flow-through sonoreactors, which come in various sizes and geometries. These reactors ensure that the ultrasound energy is applied consistently and uniformly to the cellulose material, leading to superior processing outcomes.
Hielscher bench-top sonicators, such as the UIP1000hdT, UIP2000hdT, and UIP4000hdT, are capable of producing several kilograms of nanocellulose daily, making them suitable for mid-scale production needs. For large-scale commercial production, the full industrial units like the UIP10000 and UIP16000hdT can handle extensive mass streams, enabling the efficient production of high volumes of nanocellulose.
One of the most significant advantages of Hielscher ultrasonic systems is their linear scalability. Both bench-top and industrial ultrasonicators can be installed in clusters, providing virtually unlimited processing capacity, making them an ideal choice for operations requiring high throughput and reliable performance in the production of nanocellulose.
- high degree of fibrillation
- high nanocellulose yield
- thin fibers
- detangled fibers

Hielscher’s lab ultrasonicator UP400S (400W, 24kHz)
The table below gives you an indication of the approximate processing capacity of our ultrasonicators:
Batch Volume | Flow Rate | Recommended Devices |
---|---|---|
0.5 to 1.5mL | n.a. | VialTweeter |
1 to 500mL | 10 to 200mL/min | UP100H |
10 to 2000mL | 20 to 400mL/min | UP200Ht, UP400St |
0.1 to 20L | 0.2 to 4L/min | UIP2000hdT |
10 to 100L | 2 to 10L/min | UIP4000hdT |
15 to 150L | 3 to 15L/min | UIP6000hdT |
n.a. | 10 to 100L/min | UIP16000 |
n.a. | larger | cluster of UIP16000 |
What is Nanocellulose?
Nanocellulose includes different types of cellulose nanofibers (CNF), which can be distinguished in microfibrillated cellulose (MFC), nanocrystalline cellulose (NCC), and bacterial nanocellulose. The latter refers to nano-structured cellulose produced by bacteria.
Nanocellulose shows outstanding properties such as an extraordinary strength and stiffness, high crystallinity, thixotropy, as well as a high concentration of hydroxyl group on its surface. Many of the high performance characteristics of nanocellulose are caused by its high surface/mass ratio.
Nanocelluloses are widely used in medicine and pharmaceuticals, electronics, membranes, porous materials, paper, and food because of their availability, biocompatibility, biological degradability, and sustainability. Due to its high performance characteristics, nanocellulose is an interesting material for reinforcing plastics, the improvement of the mechanical properties of e.g. thermosetting resins, starch-based matrixes, soy protein, rubber latex, or poly(lactide). For composite applications, nanocellulose is used for coatings and films, paints, foams, packaging. Furthermore, nanocellulose is a promising component to make aerogels and foams, either in homogeneous formulations or in composites.
Abreviations:
Nanocrystalline Cellulose (NCC)
Cellulose Nanofibers (CNF)
Microfibrillated Cellulose (MFC)
Nanocellulose Whiskers (NCW)
Cellulose Nanocrystals (CNC)
Literature / References
- E. Abraham, B. Deep, L.A. Pothan, M. Jacob, S. Thomas, U. Cvelbar, R. Anandjiwala (2011): Extraction of nanocellulose fibrils from lignocellulosic fibres: A novel approach. Carbohydrate Polymers 86, 2011. 1468–1475.
- E. Bittencourt, M. de Camargo (2011): Preliminary Studies on the Production of Nanofibrils of Cellulose from Never Dried Cotton, using Eco-friendly Enzymatic Hydrolysis and High-energy Sonication. 3rd Int’l. Workshop: Advances in Cleaner Production. Sao Paulo, Brazil, May 18th – 20th 2011.
- L. S. Blachechen, J. P. de Mesquita, E. L. de Paula, F. V. Pereira, D. F. S. Petri (2013): Interplay of colloidal stability of cellulose nanocrystals and their dispersibility in cellulose acetate butyrate matrix. Cellulose 2013.
- A. Dufresne (2012): Nanocellulose: From Nature to High Performance Tailored Materials. Walter de Gruyter, 2012.
- M. A. Hubbe; O. J. Rojas; L. A. Lucia, M. Sain (2008): Cellulosic Nanocomposites: A Review. BioResources 3/3, 2008. 929-980.
- S. P. Mishra, A.-S. Manent, B. Chabot, C. Daneault (2012): Production of Nanocellulose from Native Cellulose – Various Options using Ultrasound. BioResources 7/1, 2012. 422-436.
- Matjaž Kunaver, Alojz Anžlovar, Ema Žagar (2016): The fast and effective isolation of nanocellulose from selected cellulosic feedstocks. Carbohydrate Polymers, Volume 148, 2016. 251-258.
- http://en.wikipedia.org/wiki/Nanocellulose