, Aerogels' density and S BET when coagulated in H 2 O as a function of DP. Dashed lines are trend curves

, Pulp aerogels' density as a function of type

. .. , Shrinkage of aerogels as a function of pulp's type, p.229

, Pulp aerogels' density as a function of DP, by type of pulp for HCl and EtOH non-solvents

. .. Morphology, , p.231

, Size distribution of pulp aerogel beads

, )h-h-h aerogels (top) and xerogels (bottom) as a function of coagulation bath

, )h-h-h (left) and (2)h-h-l (right) aerogels' and xerogels' sorption cycles, vol.233, p.235

. List and . Tables, Pulp aerogels' characteristics as a function of gelation time, p.218

, Solubility of NaOH and ZnO in the non-solvents in g L ?, vol.1, p.219, 1998.

, Pulp aerogels' metal content and crystallinity as a function of the type of coagulation bath. Measurement performed by RISE-Innventia, p.219

, Composition of pulp aerogels as a function of coagulation bath, p.220

, Specific surface area (S BET ) of hemicellulose, cellulose and hemicellulosecellulose hybrid aerogels

, Rheology of cellulose-[DBNH][Pr] solutions and shaping into aerogel beads Bulk density, specific surface area and morphology, p.131

. .. , , p.133

.. .. Conclusions,

.. .. Abstract,

.. .. Résumé,

. .. Materials,

, Hemicellulose and hemicellulose-MCC hybrid aerogels' preparation

, Determination of non-dissolved fraction in pulp-NaOH-ZnO-H 2 O solutions

. .. , Shaping and different drying modes, p.213

D. .. Results, 215 6.2.1 Dissolution efficiency of NaOH solvent for the pulps, p.217

, Influence of coagulation bath type

, Prospects: application and variation of shaping and drying, p.230

. .. , Pulp based aerogels in shape of beads, p.230

.. .. Vacuum,

.. .. Conclusions,

O. References-aaltonen and O. Jauhiainen, The preparation of lignocellulosic aerogels from ionic liquid solutions. Carbohydrate Polymers, vol.75, pp.125-129, 2009.

M. A. Aegerter, N. Leventis, and M. M. Koebel, Aerogels Handbook, Advances in Sol-Gel Derived Materials and Technologies, vol.73, 2011.

M. Alnaief, M. A. Alzaitoun, C. A. García-gonzález, and I. Smirnova, Preparation of biodegradable nanoporous microspherical aerogel based on alginate, Carbohydrate Polymers, vol.84, issue.3, p.85, 2011.

M. Alnaief, R. Obaidat, and H. Mashaqbeh, Effect of processing parameters on preparation of carrageenan aerogel microparticles, Carbohydrate Polymers, vol.180, p.85, 2018.

J. Andanson, E. Bordes, J. Devémy, F. Leroux, A. A. Pádua et al., Understanding the role of co-solvents in the dissolution of cellulose in ionic liquids, Green Chem, vol.16, issue.5, p.63, 2014.
URL : https://hal.archives-ouvertes.fr/hal-01084934

R. H. Atalla and D. L. Vanderhart, The role of solid state 13c NMR spectroscopy in studies of the nature of native celluloses, Solid State Nuclear Magnetic Resonance, issue.15, p.54, 1999.

F. Ayadi and A. Tourrette, Procédé de préparation d'un matériau poreux a base de cellulose, matériaux obtenus et utilisations, Patent FR, vol.3, p.196, 2015.

K. C. Badgujar and B. M. Bhanage, Factors governing dissolution process of lignocellulosic biomass in ionic liquid: Current status, overview and challenges, Bioresource Technology, vol.178, p.63, 2015.

A. A. Baker, W. Helbert, J. Sugiyama, and M. J. Miles, High-Resolution Atomic Force Microscopy of NativeValoniaCellulose I Microcrystals, BASF 2019. SLENTITE® -High-performance insulation with organic aerogel, vol.119, p.11, 1997.

V. Baudron, P. Gurikov, and I. Smirnova, A continuous approach to the emulsion gelation method for the production of aerogel micro-particle, Colloids and Surfaces A: Physicochemical and Engineering Aspects, vol.566, p.85, 2019.

O. Biganska and P. Navard, Morphology of cellulose objects regenerated from cellulose-Nmethylmorpholine N-oxide-water solutions, Cellulose, vol.16, issue.2, p.179, 2008.

J. Blachot, N. Brunet, P. Navard, and J. Cavaille, Rheological behavior of cellulose/monohydrate of n-methylmorpholine n-oxide solutions Part 1: Liquid state, Rheologica acta, vol.37, issue.2, p.127, 1998.
URL : https://hal.archives-ouvertes.fr/hal-00673787

A. Borisova, M. D. Bruyn, V. L. Budarin, P. S. Shuttleworth, J. R. Dodson et al., A Sustainable Freeze-Drying Route to Porous Polysaccharides with Tailored Hierarchical Meso-and Macroporosity, Macromolecular Rapid Communications, vol.36, issue.8, p.72, 2015.

N. Buchtová and T. Budtova, Cellulose aero-, cryo-and xerogels: towards understanding of morphology control, Cellulose, vol.23, issue.4, pp.2585-2595, 2016.

T. Budtova, Cellulose II aerogels: a review, Cellulose, vol.26, issue.1, p.82, 2019.
URL : https://hal.archives-ouvertes.fr/hal-02419114

T. Budtova and P. Navard, Cellulose in NaOH-water based solvents: a review, Cellulose, vol.23, issue.1, pp.5-55, 2016.
URL : https://hal.archives-ouvertes.fr/hal-02420046

, CabotCorp 2019. Aerogel, p.73

J. Cai, S. Kimura, M. Wada, S. Kuga, and L. Zhang, Cellulose Aerogels from Aqueous Alkali Hydroxide-Urea Solution. Chem-SusChem, vol.1, issue.1-2, p.36, 2008.

J. Cai and L. Zhang, Rapid Dissolution of Cellulose in LiOH/Urea and NaOH/Urea Aqueous Solutions, Macromolecular Bioscience, vol.5, issue.6, p.143, 2005.

J. Cai and L. Zhang, Unique Gelation Behavior of Cellulose in NaOH/Urea Aqueous Solution, Biomacromolecules, vol.7, issue.1, p.147, 2006.

J. Cai, L. Zhang, S. Liu, Y. Liu, X. Xu et al., Dynamic Self-Assembly Induced Rapid Dissolution of Cellulose at Low Temperatures, Macromolecules, vol.41, issue.23, p.61, 2008.

E. Chan, B. Lee, P. Ravindra, and D. Poncelet, Prediction models for shape and size of ca-alginate macrobeads produced through extrusion-dripping method, Journal of Colloid and Interface Science, vol.338, issue.1, p.66, 2009.

X. Chang, D. Chen, and X. Jiao, Chitosan-Based Aerogels with High Adsorption Performance, J. Phys. Chem. B, vol.112, issue.26, p.78, 2008.

W. Chen, H. Yu, Q. Li, Y. Liu, and J. Li, Ultralight and highly flexible aerogels with long cellulose I nanofibers, Soft Matter, vol.7, issue.21, p.77, 2011.

D. Ciolacu, F. Ciolacu, and V. I. Popa, Amorphous cellulose -Structure and characterization, Cellulose Chemistry and Technology, vol.45, p.107, 2011.

D. Ciolacu, C. Rudaz, M. Vasilescu, and T. Budtova, Physically and chemically cross-linked cellulose cryogels: Structure, properties and application for controlled release, Carbohydrate Polymers, vol.151, p.74, 2016.
URL : https://hal.archives-ouvertes.fr/hal-01354077

W. P. Cox and E. H. Merz, Correlation of dynamic and steady flow viscosities, J. Polym. Sci, vol.28, issue.118, p.124, 1958.

C. Cuissinat and P. Navard, Swelling and Dissolution of Cellulose Part 1: Free Floating Cotton and Wood REFERENCES Fibres in N-Methylmorpholine-N-oxide-Water Mixtures, Macromolecular Symposia, vol.244, issue.1, p.64, 2006.

C. Cuissinat and P. Navard, Swelling and Dissolution of Cellulose Part II: Free Floating Cotton and Wood Fibres in NaOH-Water-Additives Systems, Macromolecular Symposia, vol.244, p.64, 2006.
URL : https://hal.archives-ouvertes.fr/hal-00530634

C. Cuissinat and P. Navard, Swelling and dissolution of cellulose, Part III: plant fibres in aqueous systems, Cellulose, vol.15, issue.1, p.64, 2008.
URL : https://hal.archives-ouvertes.fr/hal-00509599

C. Cuissinat, P. Navard, and T. Heinze, Swelling and dissolution of cellulose, Part V: cellulose derivatives fibres in aqueous systems and ionic liquids, Cellulose, vol.15, issue.1, p.64, 2008.
URL : https://hal.archives-ouvertes.fr/hal-00509600

G. F. Davidson, The Dissolution of Chemically Modified Cotton Cellulose in Alkaline Solutions. Part I: In Solutions of Sodium Hydroxide, Particularly at Temperatures Below the Normal, Journal of the Textile Institute Transactions, vol.25, issue.5, p.59, 1934.

G. F. Davidson, The Dissolution of Chemically Modified Cotton Cellulose in Alkaline Solutions, Solutions of Sodium and Potassium Hydroxide Containing Dissolved Zinc, Beryllium and Aluminium Oxides, vol.3, p.61, 1937.

R. De-bruijn, Tipstreaming of drops in simple shear flows, Chemical Engineering Science, vol.48, issue.2, pp.277-284, 1993.

F. De-cicco, P. Russo, E. Reverchon, C. A. García-gonzález, R. P. Aquino et al., Prilling and supercritical drying: A successful duo to produce core-shell polysaccharide aerogel beads for wound healing, Carbohydrate Polymers, vol.147, p.84, 2016.

D. Marco, I. , L. Baldino, S. Cardea, and E. Reverchon, Supercritical gel drying for the production of starch aerogels for delivery systems, Chemical Engineering Transactions, p.77, 2015.

D. Marco, I. , S. Riemma, and R. Iannone, Life cycle assessment of supercritical impregnation: Starch aerogel + ?-REFERENCES tocopherol tablets, The Journal of Supercritical Fluids, vol.143, p.77, 2019.

W. De-oliveira and W. G. Glasser, Hydrogels from Polysaccharides. I. Cellulose Beads for chromatographic support-Glasser.pdf, Journal of Applied Polymer Science, vol.60, p.66, 1996.

A. Demilecamps, G. Reichenauer, A. Rigacci, and T. Budtova, Cellulose-silica composite aerogels from "one-pot, synthesis. Cellulose, vol.21, issue.4, p.224, 2014.
URL : https://hal.archives-ouvertes.fr/hal-02420163

M. Desse, B. Wolf, J. Mitchell, and T. Budtova, Experimental study of the break-up of starch suspension droplets in step-up shear flow, Journal of Rheology, vol.53, issue.4, p.110, 2009.
URL : https://hal.archives-ouvertes.fr/hal-00508428

B. Ding, J. Cai, J. Huang, L. Zhang, Y. Chen et al., Facile preparation of robust and biocompatible chitin aerogels, J. Mater. Chem, vol.22, p.78, 2012.

T. P. Dirkse, C. Postmus, and R. Vandenbosch, A Study of Alkaline Solutions of Zinc Oxide, J. Am. Chem. Soc, vol.76, issue.23, p.218, 1954.

L. Druel, R. Bardl, W. Vorwerg, and T. Budtova, Starch Aerogels: A Member of the Family of Thermal Superinsulating Materials, Biomacromolecules, vol.18, issue.12, pp.4232-4239, 2017.
URL : https://hal.archives-ouvertes.fr/hal-02419331

L. Druel, P. Niemeyer, B. Milow, and T. Budtova, , 2018.

, Cited on pages 38, vol.20, pp.3993-4002

S. Dumitriu, Polysaccharides: Structural Diversity and Functional Versatility, p.51, 2004.

A. Ebringerová, Z. Hromádková, and T. Heinze, Hemicellulose. In Polysaccharides I, vol.186, p.51, 2005.

J. Eckelt, A. Knopf, T. Röder, H. K. Weber, H. Sixta et al., Viscosity-molecular weight relationship for cellulose solutions in either NMMO monohydrate or cuen, Journal of Applied Polymer Science, vol.119, issue.2, pp.670-676, 2011.

M. Egal, Structure and properties of cellulose / NaOH aqueous solutions, gels and regenerated objects, 2006.
URL : https://hal.archives-ouvertes.fr/pastel-00002229

M. Egal, T. Budtova, and P. Navard, Structure of Aqueous Solutions of Microcrystalline Cellulose/Sodium Hydroxide below 0°C and the Limit of Cellulose Dissolution, Biomacromolecules, vol.8, issue.7, p.60, 2007.
URL : https://hal.archives-ouvertes.fr/hal-00574192

O. A. El-seoud, A. Koschella, L. C. Fidale, S. Dorn, and T. Heinze, Applications of ionic liquids in carbohydrate chemistry: A window of opportunities, Biomacromolecules, vol.8, issue.9, pp.2629-2647, 2007.

T. Elschner, K. Ganske, and T. Heinze, Synthesis and aminolysis of polysaccharide carbonates, Cellulose, vol.20, issue.1, p.61, 2013.

R. Evans and A. F. Wallis, Cellulose molecular weights determined by viscometry, Journal of Applied Polymer Science, vol.37, issue.8, pp.2331-2340, 1989.

P. M. Froass, A. J. Ragauskas, and J. E. Jiang, Analysis of Lignin from Modern Kraft Pulping Technologies, Jiang.pdf. Holzforschung, vol.3, p.216, 1998.

K. Ganesan, T. Budtova, L. Ratke, P. Gurikov, V. Baudron et al., Review on the Production of, Polysaccharide Aerogel Particles. Materials, vol.11, issue.11, p.2144, 2018.
URL : https://hal.archives-ouvertes.fr/hal-02419176

K. Ganesan, A. Dennstedt, A. Barowski, and L. Ratke, Design of aerogels, cryogels and xerogels of cellulose with hierarchical porous structures, Materials & Design, vol.92, p.79, 2016.

K. Ganesan and L. Ratke, Facile preparation of monolithic ?-carrageenan aerogels, Soft Matter, vol.10, issue.18, p.78, 2014.

C. García-gonzález, M. Camino-rey, M. Alnaief, C. Zetzl, and I. Smirnova, Supercritical drying of aerogels using CO2: Effect of extraction time on the end material textural properties, The Journal of Supercritical Fluids, vol.66, p.77, 2012.

C. García-gonzález and I. Smirnova, Use of supercritical fluid technology for the production of tailor-made aerogel particles for delivery systems, The Journal of Supercritical Fluids, vol.79, pp.152-158, 2013.

C. García-gonzález, J. Uy, M. Alnaief, and I. Smirnova, Preparation of tailor-made starch-based aerogel microspheres by the emulsion-gelation method, Carbohydrate Polymers, vol.88, issue.4, pp.1378-1386, 2012.

C. A. García-gonzález, M. Alnaief, and I. Smirnova, Polysaccharide-based aerogels-Promising biodegradable carriers for drug delivery systems, Carbohydrate Polymers, vol.86, issue.4, pp.1425-1438, 2011.

C. A. García-gonzález, E. Carenza, M. Zeng, I. Smirnova, and A. Roig, Design of biocompatible magnetic pectin aerogel monoliths and microspheres, RSC Adv, vol.2, issue.26, pp.9816-9823, 2012.

C. A. García-gonzález, M. Jin, J. Gerth, C. Alvarez-lorenzo, and I. Smirnova, Polysaccharide-based aerogel microspheres for oral drug delivery, Carbohydrate Polymers, vol.117, pp.797-806, 2015.

E. S. Gardiner and A. Sarko, Packing analysis of carbohydrates and polysaccharides, Canadian Journal of Chemistry, vol.16, issue.1, p.56, 1985.

R. Gavillon, Preparation and characterization of ultra porous cellulosic materials, vol.37, 2007.
URL : https://hal.archives-ouvertes.fr/tel-00173409

R. Gavillon and T. Budtova, Kinetics of Cellulose Regeneration from Cellulose-NaOH-Water Gels and Comparison with Cellulose-N-Methylmorpholine-N-Oxide-Water Solutions, Biomacromolecules, vol.8, issue.2, p.75, 2007.
URL : https://hal.archives-ouvertes.fr/hal-00522031

R. Gavillon and T. Budtova, Aerocellulose: New Highly Porous Cellulose Prepared from Cellulose-NaOH Aqueous Solutions, Biomacromolecules, vol.9, issue.1, pp.269-277, 2008.
URL : https://hal.archives-ouvertes.fr/hal-00509828

G. Gellerstedt and E. Lindfors, Structural changes in lignin during kraft cooking. Part 4. Phenolic hydroxyl REFERENCES groups in wood and kraft pulps, Svensk Papperstidning, vol.87, issue.15, p.216, 1984.

M. Gericke, T. Liebert, O. A. Seoud, and T. Heinze, Tailored Media for Homogeneous Cellulose Chemistry: Ionic Liquid/Co-Solvent Mixtures, Macromol. Mater. Eng, vol.296, issue.6, p.121, 2011.

M. Gericke, K. Schlufter, T. Liebert, T. Heinze, and T. Budtova, Rheological Properties of Cellulose/Ionic Liquid Solutions: From Dilute to Concentrated States, Biomacromolecules, vol.10, issue.5, pp.1188-1194, 2009.
URL : https://hal.archives-ouvertes.fr/hal-00509464

M. Gericke, J. Trygg, and P. Fardim, Functional Cellulose Beads: Preparation, Characterization, and Applications, Chemical Reviews, vol.113, issue.7, pp.4812-4836, 2013.

G. M. Glenn and D. W. Irving, Starch-based microcellular foams, Cereal chemistry, vol.72, issue.2, p.77, 1995.

H. P. Grace, Dispersion Phenomena in High Viscosity Immiscible Fluid Systems and Application of Static Mixers as Dispersion Devices in Such Systems, Chemical Engineering Communications, vol.14, issue.3-6, pp.225-277, 1982.

C. Graenacher, Cellulose solution. U.S. Patent 1,943,176, p.62, 1934.

S. M. Green, Understanding Ionic Liquid Properties for Carbohydrate Dissolution, 2017.

S. Groult and T. Budtova, Thermal conductivity/structure correlations in thermal super-insulating pectin aerogels, Carbohydrate Polymers, vol.196, pp.73-81, 2018.
URL : https://hal.archives-ouvertes.fr/hal-02420006

S. Groult and T. Budtova, Tuning structure and properties of pectin aerogels, European Polymer Journal, vol.108, pp.250-261, 2018.
URL : https://hal.archives-ouvertes.fr/hal-02419292

M. Gunnarsson, Investigation of CO2 interactions with cellulose dissolved in the NaOH(aq) REFERENCES system, 2017.

M. Gunnarsson, D. Bernin, Å. Östlund, and M. Hasani, The CO2 capturing ability of cellulose dissolved in NaOH(aq) at low temperature, Green Chem, vol.20, issue.14, pp.3279-3286, 2018.

M. Gunnarsson, H. Theliander, and M. Hasani, Chemisorption of air CO2 on cellulose: an overlooked feature of the cellulose/NaOH(aq) dissolution system, Cellulose, vol.24, issue.6, pp.2427-2436, 2017.

P. Gurikov, S. P. Raman, D. Weinrich, M. Fricke, and I. Smirnova, A novel approach to alginate aerogels: carbon dioxide induced gelation, RSC Adv, vol.5, issue.11, p.78, 2015.

E. Haimer, M. Wendland, K. Schlufter, K. Frankenfeld, P. Miethe et al., Loading of Bacterial Cellulose Aerogels with Bioactive Compounds by Antisolvent Precipitation with Supercritical Carbon Dioxide, Macromolecular Symposia, vol.294, issue.2, p.77, 2010.

L. K. Hauru, M. Hummel, A. W. King, I. Kilpeläinen, and H. Sixta, Role of Solvent Parameters in the Regeneration of Cellulose from Ionic Liquid Solutions, Biomacromolecules, vol.13, issue.9, p.63, 2012.

L. K. Hauru, M. Hummel, K. Nieminen, A. Michud, and H. Sixta, Cellulose regeneration and spinnability from ionic liquids, Soft Matter, vol.12, issue.5, p.63, 2016.

L. Heath and W. Thielemans, Cellulose nanowhisker aerogels. Green Chemistry, vol.12, issue.8, p.77, 2010.

S. Hoepfner, L. Ratke, and B. Milow, Synthesis and characterisation of nanofibrillar cellulose aerogels, Cellulose, vol.15, issue.1, pp.121-129, 2008.

D. N. Hon, .. , and N. Shiraishi, Wood and Cellulosic Chemistry, Second Edition, Revised, and Expanded, 2000.

J. Innerlohinger, H. K. Weber, and G. Kraft, Aerocellulose: Aerogels and Aerogel-like Materials made from Cellulose, REFERENCES Macromolecular Symposia, vol.244, issue.1, pp.126-135, 2006.

N. Isobe, U. Kim, S. Kimura, M. Wada, and S. Kuga, Internal surface polarity of regenerated cellulose gel depends on the species used as coagulant, Journal of Colloid and Interface Science, vol.359, issue.1, p.81, 2011.

N. Isobe, S. Kimura, M. Wada, and S. Kuga, Mechanism of cellulose gelation from aqueous alkali-urea solution. Carbohydrate Polymers, vol.89, p.62, 2012.

N. Isobe, K. Noguchi, Y. Nishiyama, S. Kimura, M. Wada et al., Role of urea in alkaline dissolution of cellulose, Cellulose, vol.20, issue.1, p.61, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00787592

A. Isogai and R. H. Atalla, Dissolution of Cellulose in, Aqueous NaOH Solutions. Cellulose, vol.5, pp.309-319, 1998.

A. Isogai, M. Usuda, T. Kato, T. Uryu, and R. H. Atalla, Solid-state CP/MAS carbon-13 NMR study of cellulose polymorphs, Macromolecules, vol.22, issue.7, p.197, 1989.

Z. Jiang, Y. Fang, J. Xiang, Y. Ma, A. Lu et al., Intermolecular Interactions and 3d Structure in Cellulose-NaOH-Urea Aqueous System, J. Phys. Chem. B, vol.118, issue.34, p.61, 2014.

C. Jiménez-saelices, B. Seantier, B. Cathala, and Y. Grohens, Spray freeze-dried nanofibrillated cellulose aerogels with thermal superinsulating properties, Carbohydrate Polymers, vol.157, pp.105-113, 2017.

H. Jin, M. Kettunen, A. Laiho, H. Pynnönen, J. Paltakari et al., Superhydrophobic and Superoleophobic Nanocellulose Aerogel Membranes as Bioinspired Cargo Carriers on Water and Oil, Langmuir, vol.27, issue.5, p.77, 2011.

S. M. Kamal-mohamed, K. Ganesan, B. Milow, and L. Ratke, The effect of zinc oxide (ZnO) addition on the physical and morphological properties of cellulose aerogel beads, RSC Adv, vol.5, issue.109, p.66, 2015.

K. Kamide, K. Okajima, and K. Kowsaka, Dissolution of natural cellulose into aqueous alkali solution: role of supermolecular structure of cellulose, Polymer Journal, vol.24, issue.1, p.60, 1992.

K. Kamide, K. Okajima, T. Matsui, and K. Kowsaka, Study on the Solubility of Cellulose in Aqueous Alkali Solution by Deuteration IR and 13 C NMR, Polymer Journal, vol.16, issue.12, p.60, 1984.

I. Karadagli, B. Schulz, M. Schestakow, B. Milow, T. Gries et al., Production of porous cellulose aerogel fibers by an extrusion process, The Journal of Supercritical Fluids, vol.106, p.79, 2015.

S. K. Karatzos, L. A. Edye, and R. M. Wellard, The undesirable acetylation of cellulose by the acetate ion of 1-ethyl-3-methylimidazolium acetate, Cellulose, vol.19, issue.1, p.63, 2012.

H. Karbstein and H. Schubert, Developments in the continuous mechanical production of oil-in-water macroemulsions, Process Intensification, vol.34, p.67, 1995.

H. Kayser, C. R. Müller, C. A. García-gonzález, I. Smirnova, W. Leitner et al., Dried chitosan-gels as organocatalysts for the production of biomass-derived platform chemicals, Applied Catalysis A: General, vol.85, pp.180-186, 2012.

J. A. Kenar, F. J. Eller, F. C. Felker, M. A. Jackson, and G. F. Fanta, Starch aerogel beads obtained from inclusion complexes prepared from high amylose starch and sodium palmitate, Green Chem, vol.16, issue.4, p.84, 2014.

M. Kihlman, F. Aldaeus, F. Chedid, and U. Germgård, Effect of various pulp properties on the solubility of cellulose in sodium hydroxide solutions, Holzforschung, vol.64, issue.5, p.66, 2012.

K. K. Kim and D. W. Pack, Microspheres for Drug Delivery, BioMEMS and Biomedical Nanotechnology: Volume I Biological and Biomedical Nanotechnology, p.70, 2006.

S. S. Kistler, Coherent Expanded Aerogels and Jellies, Nature, vol.127, issue.3211, p.11, 1931.

S. S. Kistler, Coherent Expanded Aerogels, J. Phys. Chem, vol.36, pp.52-64, 1932.

D. Klemm, B. Heublein, H. Fink, and A. Bohn, Cellulose: Fascinating Biopolymer and Sustainable Raw Material, Angewandte Chemie International Edition, vol.44, issue.22, p.53, 2005.

D. Klemm, B. Philipp, T. Heinze, U. Heinze, and W. Wagenknecht, Comprehensive Cellulose Chemistry, vol.1, 1998.

Y. Kobayashi, T. Saito, and A. Isogai, Aerogels with 3d Ordered Nanofiber Skeletons of Liquid-Crystalline Nanocellulose Derivatives as Tough and Transparent Insulators, Angewandte Chemie International Edition, vol.53, issue.39, p.77, 2014.

L. M. Kroon-batenburg, J. Kroon, and M. G. Nordholt, Chain modulus and intramolecular hydrogen bonding in native and regenerated cellulose fibers, Polymer communications, vol.55, issue.27, p.35, 1986.

K. Labidi, M. O.-korhonen, A. H. Zrida, T. Hamzaoui, and . Budtova, All-cellulose composites from alfa and wood fibers, Industrial Crops and Products, vol.127, p.65, 2019.
URL : https://hal.archives-ouvertes.fr/hal-02419278

P. T. Larsson, K. Wickholm, and T. Iversen, A CP/MAS13c NMR investigation of molecular ordering in celluloses. Carbohydrate Research, vol.302, p.108, 1997.

N. Lavoine and L. Bergström, Nanocellulose-based foams and aerogels: processing, properties, and applications, J. Mater. Chem. A, vol.5, issue.31, p.77, 2017.

K. A. Le, C. Rudaz, and T. Budtova, Phase diagram, solubility limit and hydrodynamic properties of cellulose in binary solvents with ionic liquid, Carbohydr. Polym, vol.105, p.121, 2014.
URL : https://hal.archives-ouvertes.fr/hal-00960085

L. Duc, A. , B. Vergnes, and T. Budtova, Polypropylene/natural fibres composites: Analysis of fibre dimensions after compounding and observations of fibre rupture by rheo-optics, Composites Part A: Applied Science and Manufacturing, vol.42, issue.11, p.110, 2011.
URL : https://hal.archives-ouvertes.fr/hal-00623531

N. Le-moigne and P. Navard, Dissolution mechanisms of wood cellulose fibres in NaOH-water, Cellulose, vol.17, issue.1, pp.31-45, 2010.
URL : https://hal.archives-ouvertes.fr/hal-00509589

T. Liebert and T. Heinze, Interaction of ionic liquids with polysaccharides 5. Solvents and reaction media for the modification of cellulose, BioResources, vol.3, issue.2, p.62, 2008.

F. Liebner, E. Haimer, A. Potthast, D. Loidl, S. Tschegg et al., Cellulosic aerogels as ultra-lightweight materials. Part 2: Synthesis and properties 2nd ICC, Holzforschung, vol.81, issue.1, p.79, 2007.

F. Liebner, E. Haimer, M. Wendland, M. Neouze, K. Schlufter et al., Aerogels from Unaltered Bacterial Cellulose: Application of scCO2 Drying for the Preparation of Shaped, Ultra-Lightweight Cellulosic Aerogels, Macromolecular Bioscience, vol.10, issue.4, p.77, 2010.

F. Liebner, N. Pircher, C. Schimper, E. Haimer, and T. Rosenau, Aerogels: Cellulose-Based, Encyclopedia of Biomedical Polymers and Polymeric Biomaterials, pp.37-75, 2016.

F. Liebner, A. Potthast, T. Rosenau, E. Haimer, and M. Wendland, Cellulose aerogels: Highly porous, ultra-lightweight materials, Holzforschung, vol.62, issue.2, pp.129-135, 2008.

C. Lin, M. H.-y.-zhan, S. Liu, L. A. Fu, and . Lucia, Novel Preparation and Characterization of Cellulose Microparticles Functionalized in Ionic Liquids, Langmuir, vol.25, issue.17, p.115, 2009.

B. Lindman, G. Karlström, and L. Stigsson, On the mechanism of dissolution of cellulose, Journal of Molecular Liquids, vol.156, issue.1, p.57, 2010.

B. Lindman, B. Medronho, L. Alves, C. Costa, H. Edlund et al., The relevance of structural features of cellulose and its interactions to dissolution, regeneration, gelation and plasticization phenomena, Physical Chemistry Chemical Physics, vol.19, issue.35, p.60, 2017.

H. Liu, K. L. Sale, B. M. Holmes, B. A. Simmons, and S. Singh, Understanding the Interactions of Cellulose with Ionic Liquids: A Molecular Dynamics Study, J. Phys. Chem. B, vol.114, issue.12, p.63, 2010.

W. Liu and T. Budtova, Dissolution of unmodified waxy starch in ionic liquid and solution rheological properties, Carbohydrate Polymers, vol.93, issue.1, p.128, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00678047

W. Liu, T. Budtova, and P. Navard, Influence of ZnO on the properties of dilute and semi-dilute cellulose-NaOHwater solutions, Cellulose, vol.18, issue.4, p.61, 2011.

Y. Liu, Study of Tin Cementation in Alkaline Solution, J. Electrochem. Soc, vol.145, issue.1, p.5, 1998.

C. López-iglesias, J. Barros, I. Ardao, F. J. Monteiro, C. Alvarez-lorenzo et al., Vancomycin-loaded chitosan aerogel particles for chronic wound applications, Carbohydr Polym, vol.204, p.78, 2019.

D. D. Lovskaya, A. E. Lebedev, and N. V. Menshutina, Aerogels as drug delivery systems: In vitro and in vivo evaluations, The Journal of Supercritical Fluids, vol.106, p.84, 2015.

B. Lu, A. Xu, and J. Wang, Cation does matter: how cationic structure affects the dissolution of cellulose in ionic liquids, Green Chem, vol.16, issue.3, p.63, 2014.

X. Luo, S. Liu, J. Zhou, and L. Zhang, In situ synthesis of Fe3o4/cellulose microspheres with magnetic-induced protein delivery, Journal of Materials Chemistry, vol.19, issue.21, p.70, 2009.

X. Luo and L. Zhang, Creation of regenerated cellulose microspheres with diameter ranging from micron to millimeter for chromatography applications, Journal of Chromatography A, vol.1217, issue.38, pp.5922-5929, 2010.

X. Luo and L. Zhang, Immobilization of Penicillin G Acylase in Epoxy-Activated Magnetic Cellulose Microspheres for Improvement of Biocatalytic Stability and Activities, Biomacromolecules, vol.11, issue.11, p.70, 2010.

Y. Ma, S. Asaadi, L. Johansson, P. Ahvenainen, M. Reza et al., High-Strength Composite Fibers from Cellulose-Lignin Blends Regenerated REFERENCES from Ionic Liquid Solution, ChemSusChem, vol.8, issue.23, pp.4030-4039, 2015.

L. Manzocco, F. Valoppi, S. Calligaris, F. Andreatta, S. Spilimbergo et al., Exploitation of ?-carrageenan aerogels as template for edible oleogel preparation, Food Hydrocolloids, vol.71, p.78, 2017.

T. Matsumoto, D. Tatsumi, N. Tamai, and T. Takaki, Solution properties of celluloses from different biological origins in LiCl· DMAc, Cellulose, vol.8, issue.4, p.127, 2001.

M. Mazza, C. D.-a.-catana, C. Vaca-garcia, and . Cecutti, Influence of water on the dissolution of cellulose in selected ionic liquids, Cellulose, vol.16, issue.2, p.63, 2009.
URL : https://hal.archives-ouvertes.fr/hal-02067524

, Probing cellulose amphiphilicity. Nordic Pulp and Paper Research Journal, vol.30, p.57, 2015.

B. Medronho and B. Lindman, Competing forces during cellulose dissolution: From solvents to mechanisms, Current Opinion in Colloid & Interface Science, vol.19, issue.1, p.35, 2014.

B. Medronho, A. Romano, M. G. Miguel, L. Stigsson, and B. Lindman, Rationalizing cellulose (in)solubility: reviewing basic physicochemical aspects and role of hydrophobic interactions, Cellulose, vol.19, issue.3, p.60, 2012.

T. Mehling, I. Smirnova, U. Guenther, and R. Neubert, Polysaccharide-based aerogels as drug carriers, Journal of Non-Crystalline Solids, vol.355, p.77, 2009.

E. Melro, L. Alves, F. E. Antunes, and B. Medronho, A brief overview on lignin dissolution, Journal of Molecular Liquids, vol.265, p.51, 2018.

N. V. Menshutina, D. D. Lovskaya, A. E. Lebedev, and E. A. Lebedev, Production of Sodium Alginate-Based Aerogel Particles Using Supercritical Drying in Units with Different Volumes. Russ, J. Phys. Chem. B, vol.11, issue.8, p.85, 2017.

J. Mercer, Improvements in the preparation of cotton and others fabrics and other fibrous materials, British Patent, vol.13, p.59, 1850.

Q. Mi, S. Ma, J. Yu, J. He, and J. Zhang, Flexible and Transparent Cellulose Aerogels with Uniform Nanoporous Structure by a Controlled Regeneration Process, ACS Sustainable Chem. Eng, vol.4, issue.3, p.79, 2016.

A. Michud, M. Tanttu, S. Asaadi, Y. Ma, E. Netti et al., Ioncell-F: ionic liquid-based cellulosic textile fibers as an alternative to viscose and Lyocell, Textile Research Journal, vol.86, issue.5, p.64, 2016.

, Project | nanohybrids, Nanohybrids, vol.18, p.12, 2019.

R. H. Newman, Simulation of X-ray diffractograms relevant to the purported polymorphs cellulose IVI and IVII, Cellulose, vol.15, issue.6, p.56, 2008.

T. Nishino, I. Matsuda, and K. Hirao, All-Cellulose Composite, Macromolecules, vol.37, issue.20, p.65, 2004.

R. M. Obaidat, M. Alnaief, and H. Mashaqbeh, Investigation of Carrageenan Aerogel Microparticles as a Potential Drug Carrier, AAPS PharmSciTech, vol.19, issue.5, p.85, 2018.

T. Okano and A. Sarko, Mercerization of cellulose. II. Alkali-cellulose intermediates and a possible mercerization mechanism, Journal of Applied Polymer Science, vol.30, issue.1, p.59, 1985.

S. Ookuma, K. Igarashi, M. Hara, K. Aso, H. Yoshidome et al., Porous ion-exchanged fine cellulose particles, method for production thereof, and affinity carrier. US005196527A, vol.85, p.79, 1993.

M. Pääkkö, J. Vapaavuori, R. Silvennoinen, H. Kosonen, M. Ankerfors et al., Long and entangled native cellulose I nanofibers allow flexible aerogels and hierarchically porous templates for functionalities, Soft Matter, vol.4, issue.12, p.77, 2008.

A. Parviainen, A. W. King, I. Mutikainen, M. Hummel, C. Selg et al.,

H. Sixta and I. Kilpeläinen, Predicting Cellulose Solvating Capabilities of Acid-Base Conjugate Ionic Liquids, ChemSusChem, vol.6, issue.11, pp.2161-2169, 2013.

A. Parviainen, R. Wahlström, U. Liimatainen, T. Liitiä, S. Rovio et al., Sustainability of cellulose dissolution and regeneration in 1,5-diazabicyclo, vol.5, p.117, 2015.

A. Pereira, H. Duarte, P. Nosrati, M. Gubitosi, L. Gentile et al., Cellulose gelation in NaOH solutions is due to cellulose crystallization, Cellulose, vol.25, issue.6, pp.3205-3210, 2018.

M. Pinnow, H. Fink, C. Fanter, and J. Kunze, Characterization of Highly Porous Materials from Cellulose Carbamate, Macromolecular Symposia, vol.262, issue.1, p.67, 2008.

N. Pircher, L. Carbajal, C. Schimper, M. Bacher, H. Rennhofer et al., Impact of selected solvent systems on the pore and solid structure of cellulose aerogels, Cellulose, vol.23, issue.3, pp.1949-1966, 2016.
URL : https://hal.archives-ouvertes.fr/hal-01317471

, PlasticsEurope, p.53, 2019.

D. Poncelet, R. Lencki, C. Beaulieu, J. P. Halle, R. J. Neufeld et al., Production of alginate beads by emulsification/internal gelation. I. Methodology, Appl Microbiol Biotechnol, vol.38, issue.1, p.70, 1992.

I. Preibisch, P. Niemeyer, Y. Yusufoglu, P. Gurikov, B. Milow et al., Polysaccharide-Based Aerogel Bead Production via, Jet Cutting Method. Materials, vol.11, issue.8, p.84, 2018.

U. Prüße, Bead production with JetCutting and rotating disk/nozzle technologies. Landbauforschung Völkenrode, P, vol.11, p.67, 2002.

U. Prüsse, L. Bilancetti, M. Bu?ko, B. Bugarski, J. Bukowski et al., Comparison of different technologies for alginate beads production, Chemical Papers, issue.4, p.67, 2008.

U. Prüße, F. Bruske, J. Breford, and K. Vorlop, Improvement of the Jet Cutting Method for the Preparation of Spherical Particles from Viscous Polymer Solutions, Chemical Engineering & Technology, vol.21, issue.2, p.67, 1998.

U. Prüße, B. Fox, M. Kirchhoff, F. Bruske, J. Breford et al., New Process (Jet Cutting Method) for the Production of Spherical Beads from Highly Viscous Polymer Solutions, Chemical Engineering & Technology, vol.21, issue.1, p.67, 1998.

U. Prüße, U. Jahnz, P. Wittlich, and K. Vorlop, Scale-up of the JetCutter technology, Chem. Ind, vol.57, issue.12, p.67, 2003.

F. Quignard, F. D. Renzo, and E. Guibal, From Natural Polysaccharides to Materials for Catalysis, Adsorption, and Remediation. In Carbohydrates in Sustainable Development, Topics in Current Chemistry, vol.85, p.78, 2010.
URL : https://hal.archives-ouvertes.fr/hal-00523443

F. Quignard, R. Valentin, and F. D. Renzo, Aerogel materials from marine polysaccharides, New J. Chem, vol.32, issue.8, pp.1300-1310, 2008.
URL : https://hal.archives-ouvertes.fr/hal-00311053

A. Rege, M. Schestakow, I. Karadagli, L. Ratke, and M. Itskov, Micro-mechanical modelling of cellulose aerogels from molten salt hydrates, Soft Matter, vol.12, issue.34, pp.7079-7088, 2016.

C. Reichardt, Solvents and Solvent Effects in Organic Chemistry, 2006.

R. A. Reichle, K. G. Mccurdy, and L. G. Hepler, Zinc Hydroxide: Solubility Product and Hydroxy-complex Stability Constants from 12.5-75°C, Canadian Journal of Chemistry, vol.53, issue.24, p.218, 1975.

A. Ricci, L. Bernardi, C. Gioia, S. Vierucci, M. Robitzer et al., Chitosan aerogel: a recyclable, heterogeneous organocatalyst for the asymmetric direct aldol reaction in water, Chem. Commun, vol.46, issue.34, p.85, 2010.
URL : https://hal.archives-ouvertes.fr/hal-00512826

M. Robitzer, L. David, C. Rochas, F. D. Renzo, and F. Quignard, Nanostructure of Calcium Alginate Aerogels Obtained from Multistep Solvent Exchange Route, Langmuir, vol.24, issue.21, p.85, 2008.
URL : https://hal.archives-ouvertes.fr/hal-00336402

M. Robitzer, F. D. Renzo, and F. Quignard, Natural materials with high surface area. Physisorption methods for the characterization of the texture and surface of polysaccharide aerogels, Microporous and Mesoporous Materials, vol.140, issue.1-3, pp.9-16, 2011.
URL : https://hal.archives-ouvertes.fr/hal-00547222

M. Robitzer, A. Tourrette, R. Horga, R. Valentin, M. Boissière et al., Nitrogen sorption as a tool for the characterisation of polysaccharide aerogels, Carbohydrate Polymers, vol.85, issue.1, p.85, 2011.
URL : https://hal.archives-ouvertes.fr/hal-00573148

C. Roy, T. Budtova, and P. Navard, Rheological Properties and Gelation of Aqueous Cellulose-NaOH Solutions, Biomacromolecules, vol.4, issue.2, pp.259-264, 2003.
URL : https://hal.archives-ouvertes.fr/hal-00533049

C. Roy, T. Budtova, P. Navard, and O. Bedue, Structure of Cellulose-Soda Solutions at Low Temperatures, Biomacromolecules, vol.2, issue.3, p.60, 2001.
URL : https://hal.archives-ouvertes.fr/hal-00574760

C. Rudaz, Cellulose and Pectin Aerogels Towards their nano structuration, 2013.
URL : https://hal.archives-ouvertes.fr/pastel-00957296

C. Rudaz and T. Budtova, Rheological and hydrodynamic properties of cellulose acetate/ionic liquid solutions, Carbohydrate Polymers, vol.92, issue.2, p.128, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00769803

C. Rudaz, R. Courson, L. Bonnet, S. Calas-etienne, H. Sallée et al., Aeropectin: fully biomass-based mechanically strong and thermal superinsulating aerogel, Biomacromolecules, vol.15, issue.6, pp.2188-2195, 2014.
URL : https://hal.archives-ouvertes.fr/hal-01022581

F. D. Rumscheidt and S. G. Mason, Particle motions in sheared suspensions XII. Deformation and burst of fluid drops in shear and hyperbolic flow, Journal of Colloid Science, vol.16, issue.3, pp.238-261, 1961.

K. Sakai, Y. Kobayashi, T. Saito, and A. Isogai, Partitioned airs at microscale and nanoscale: thermal diffusivity in ultrahigh porosity solids of nanocellulose, Scientific Reports, vol.6, issue.1, p.77, 2016.

A. Sarko, J. Southwick, and J. Hayashi, Packing Analysis of Carbohydrates and Polysaccharides. 7. Crystal Structure of Cellulose IIII and Its Relationship to Other Cellulose Polymorphs, Macromolecules, vol.9, issue.5, p.56, 1976.

P. A. Scandinavian-pulp, SCAN-CM Standard 15:88, Viscosity in cupi-ethylenediamine solution, 1988.

M. Schestakow, I. Karadagli, and L. Ratke, Cellulose aerogels prepared from an aqueous zinc chloride salt hydrate melt, Carbohydrate Polymers, vol.137, p.36, 2016.

K. R. Seddon, A. Stark, and M. Torres, Influence of chloride, water, and organic solvents on the physical properties of ionic liquids, Pure and Applied Chemistry, vol.72, issue.12, p.63, 2000.

H. Sehaqui, Q. Zhou, and L. A. Berglund, High-porosity aerogels of high specific surface area prepared from nanofibrillated cellulose (NFC), Composites Science and Technology, vol.71, issue.13, p.77, 2011.

R. Sescousse and T. Budtova, Influence of processing parameters on regeneration kinetics and morphology of porous cellulose from cellulose-NaOH-water solutions, Cellulose, vol.16, issue.3, pp.417-426, 2009.
URL : https://hal.archives-ouvertes.fr/hal-00509260

R. Sescousse, R. Gavillon, and T. Budtova, Aerocellulose from cellulose-ionic liquid solutions: Preparation, properties and comparison with cellulose-NaOH and cellulose-NMMO routes, Carbohydrate Polymers, vol.83, issue.4, pp.1766-1774, 2011.
URL : https://hal.archives-ouvertes.fr/hal-00574148

R. Sescousse, R. Gavillon, and T. Budtova, Wet and dry highly porous cellulose beads from cellulose-NaOH-water solutions: influence of the preparation conditions on beads shape and encapsulation of inorganic particles, Journal of Materials Science, vol.46, issue.3, pp.759-765, 2011.
URL : https://hal.archives-ouvertes.fr/hal-00522043

R. Sescousse, K. A. Le, M. E. Ries, and T. Budtova, Viscosity of Cellulose-Imidazolium-Based Ionic Liquid Solutions, J. Phys. Chem. B, vol.114, issue.21, pp.7222-7228, 2010.
URL : https://hal.archives-ouvertes.fr/hal-00509754

R. Sescousse, A. Smacchia, and T. Budtova, Influence of lignin on cellulose-NaOH-water mixtures properties and on Aerocellulose morphology, Cellulose, vol.17, issue.6, p.81, 2010.
URL : https://hal.archives-ouvertes.fr/hal-00522085

X. Shen, J. L. Shamshina, P. Berton, J. Bandomir, H. Wang et al., Comparison of Hydrogels Prepared with Ionic-Liquid-Isolated vs Commercial REFERENCES Chitin and Cellulose, ACS Sustainable Chem. Eng, vol.4, issue.2, pp.471-480, 2016.

Z. Shi, Y. Liu, H. Xu, Q. Yang, C. Xiong et al., Facile dissolution of wood pulp in aqueous NaOH/urea solution by ball milling pretreatment, Industrial Crops and Products, vol.118, p.65, 2018.

Z. Shi, Q. Yang, J. Cai, S. Kuga, and Y. Matsumoto, Effects of lignin and hemicellulose contents on dissolution of wood pulp in aqueous NaOH/urea solution, Cellulose, vol.21, issue.3, p.64, 2014.

S. S. Silva, A. R. Duarte, A. P. Carvalho, J. F. Mano, and R. L. Reis, Green processing of porous chitin structures for biomedical applications combining ionic liquids and supercritical fluid technology, Acta Biomaterialia, vol.7, issue.3, p.78, 2011.

S. S. Silva, A. R. Duarte, J. F. Mano, and R. L. Reis, Design and functionalization of chitin-based microsphere scaffolds, Green Chem, vol.15, issue.11, p.85, 2013.

H. Sobue, H. Kiessig, and E. K. Hess, The cellulose-sodium hydroxide-water system as a function of the temperature, Z Phys. Chem B, vol.43, pp.309-328, 1939.

R. Starbird, C. A. García-gonzález, I. Smirnova, W. H. Krautschneider, and W. Bauhofer, Synthesis of an organic conductive porous material using starch aerogels as template for chronic invasive electrodes, Materials Science and Engineering: C, vol.37, p.84, 2014.

H. A. Stone, B. J. Bentley, and L. G. Leal, An experimental study of transient effects in the breakup of viscous drops, Journal of Fluid Mechanics, vol.173, issue.1, p.131, 1986.

X. Sun, B. Peng, Y. Ji, J. Chen, and D. Li, Chitosan(chitin)/cellulose composite biosorbents prepared using ionic liquid for heavy metal ions adsorption, AIChE Journal, vol.55, issue.8, p.66, 2009.

R. P. Swatloski, S. K. Spear, J. D. Holbrey, and R. D. Rogers, Dissolution of Cellose with Ionic Liquids, Journal of the American Chemical Society, vol.124, issue.18, p.62, 2002.

T. F. Tadros, Emulsion Formation and Stability, vol.68, p.67, 2013.

M. Takahashi, M. Ookubo, and H. Takena, Solid state 13c NMR spectra analysis of alkalicellulose, Polymer Journal, vol.23, p.60, 1991.

S. Takeshita, A. Konishi, Y. Takebayashi, S. Yoda, and K. Otake, Aldehyde Approach to Hydrophobic Modification of Chitosan Aerogels, Biomacromolecules, vol.18, issue.7, p.78, 2017.

S. Takeshita and S. Yoda, Upscaled Preparation of Trimethylsilylated Chitosan Aerogel, Ind. Eng. Chem. Res, vol.57, issue.31, p.78, 2018.

M. Tatlier, G. Munz, and S. K. Henninger, Relation of water adsorption capacities of zeolites with their structural properties, Microporous and Mesoporous Materials, vol.264, p.234, 2018.

G. I. Taylor, The formation of emulsions in definable fields of flow, Proc. R. Soc. Lond. A, vol.146, pp.501-523, 1934.

I. Terzi?, J. Ivanovi?, I. ?i?ovi?, M. L. ?kori?, N. Milosavljevi? et al., A novel chitosan gels: Supercritical CO2 drying and impregnation with thymol, Polymer Engineering & Science, vol.58, issue.12, p.78, 2018.

M. Tjahjadi, J. M. Ottino, and H. A. Stone, Estimating interfacial tension via relaxation of drop shapes and filament breakup, AIChE Journal, vol.40, issue.3, p.152, 1994.

G. Tkalec, ?. Knez, and Z. Novak, Formation of polysaccharide aerogels in ethanol, vol.5, p.74, 2015.

G. Tkalec, R. Kranvogl, A. Uzunali?, ?. Knez, and Z. Novak, Optimisation of critical parameters during alginate aerogels' production, Journal of Non-Crystalline Solids, vol.443, p.78, 2016.

J. Trygg, P. Fardim, M. Gericke, E. Mäkilä, and J. Salonen, Physicochemical design of the morphology and ultrastructure of cellulose beads, Carbohydrate Polymers, vol.93, issue.1, p.66, 2013.

J. Trygg, E. Yildir, R. Kolakovic, N. Sandler, and P. Fardim, Anionic cellulose beads for drug encapsulation and release, Cellulose, vol.21, issue.3, pp.1945-1955, 2014.

C. Tsioptsias, C. Michailof, G. Stauropoulos, and C. Panayiotou, Chitin and carbon aerogels from chitin alcogels, Carbohydrate Polymers, vol.76, issue.4, p.78, 2009.

C. Tsioptsias, A. Stefopoulos, I. Kokkinomalis, L. Papadopoulou, and C. Panayiotou, Development of micro-and nano-porous composite materials by processing cellulose with ionic liquids and supercritical CO2, Green Chemistry, vol.10, issue.9, p.132, 2008.

Y. Tsutsumi, H. Koga, Z. Qi, T. Saito, and A. Isogai, Nanofibrillar Chitin Aerogels as Renewable Base Catalysts, Biomacromolecules, vol.15, p.78, 2014.

A. Ubeyitogullari and O. N. Ciftci, Formation of nanoporous aerogels from wheat starch, Carbohydrate Polymers, vol.147, p.77, 2016.

A. Ubeyitogullari, R. Moreau, D. J. Rose, J. Zhang, and O. N. Ciftci, Enhancing the Bioaccessibility of Phytosterols Using Nanoporous Corn and Wheat Starch Bioaerogels, European Journal of Lipid Science and Technology, vol.121, issue.1, p.77, 2019.

T. Väisänen, O. Das, and L. Tomppo, A review on new bio-based constituents for natural fiber-polymer composites, Journal of Cleaner Production, vol.149, p.65, 2017.

R. Valentin, R. Horga, B. Bonelli, E. Garrone, F. D. Renzo et al., Acidity of Alginate Aerogels Studied by FTIR Spectroscopy of Probe Molecules, Macromolecular Symposia, vol.230, issue.1, p.78, 2005.

R. Valentin, K. Molvinger, F. Quignard, and D. Brunel, Supercritical CO2 dried chitosan: an efficient intrinsic heterogeneous catalyst in fine chemistry, New J. Chem, vol.27, issue.12, p.85, 2003.
URL : https://hal.archives-ouvertes.fr/hal-01363910

A. Van-heiningen, M. Tunc, Y. Gao, and D. Perez, Relationship between Alkaline Pulp Yield and the Mass Fraction and Degree of Polymerization of Cellulose in the Pulp, Journal of pulp and paper science, issue.8, p.109, 2004.

A. Veronovski, ?. Knez, and Z. Novak, Preparation of multi-membrane alginate aerogels used for drug delivery, The Journal of Supercritical Fluids, vol.79, p.85, 2013.

A. Veronovski, G. Tkalec, ?. Knez, and Z. Novak, Characterisation of biodegradable pectin aerogels and their potential use as drug carriers, Carbohydrate Polymers, vol.113, pp.272-278, 2014.

L. K. Voon, S. C. Pang, and S. F. Chin, Highly porous cellulose beads of controllable sizes derived from regenerated cellulose of printed paper wastes, Materials Letters, vol.164, p.37, 2016.

L. K. Voon, S. C. Pang, and S. F. Chin, Porous Cellulose Beads Fabricated from Regenerated Cellulose as Potential Drug Delivery Carriers, Journal of Chemistry, p.11, 2017.

K. P. Vorlop and J. Breford, Verfahren und Vorrichtung zur Herstellung von Teilchen aus einem flüssigen Medium. DE4424998A1, p.67, 1996.

M. Wada, L. Heux, and J. Sugiyama, Polymorphism of Cellulose I Family: Reinvestigation of Cellulose IVI, Biomacromolecules, vol.5, issue.4, p.56, 2004.
URL : https://hal.archives-ouvertes.fr/hal-00306777

H. Wang, G. Gurau, and R. D. Rogers, Ionic liquid processing of cellulose, Chemical Society Reviews, vol.41, issue.4, p.1519, 2012.

H. Wang, Z. Shao, M. Bacher, F. Liebner, and T. Rosenau, Fluorescent cellulose aerogels containing covalently immobilized (ZnS)x(CuInS2)1-x/ZnS (core/shell) quantum dots, Cellulose, vol.20, issue.6, p.79, 2013.

X. Wang, Y. Zhang, H. Jiang, Y. Song, Z. Zhou et al., Fabrication and characterization of nano-cellulose aerogels via supercritical CO2 drying technology, Materials Letters, vol.183, p.84, 2016.

R. J. White, V. L. Budarin, and J. H. Clark, Pectin-Derived Porous Materials, Chemistry -A European Journal, vol.16, issue.4, p.78, 2010.

K. Wickholm, P. T. Larsson, and T. Iversen, Assignment of non-crystalline forms in cellulose I by CP/MAS 13c NMR spectroscopy, Carbohydrate Research, vol.312, issue.3, p.108, 1998.

J. G. Wijmans, F. W. Altena, and C. A. Smolders, Diffusion during the immersion precipitation process, Journal of Polymer Science: Polymer Physics Edition, vol.22, issue.3, p.65, 1984.

J. G. Wijmans, J. P. Baaij, and C. A. Smolders, The mechanism of formation of microporous or skinned membranes produced by immersion precipitation, Journal of Membrane Science, vol.14, issue.3, p.65, 1983.

B. A. Wolf, Polyelectrolytes Revisited: Reliable Determination of Intrinsic Viscosities, Macromolecular Rapid Communications, vol.28, issue.2, pp.164-170, 2007.

A. Xu, J. Wang, and H. Wang, Effects of anionic structure and lithium salts addition on the dissolution of cellulose in 1-butyl-3-methylimidazolium-based ionic liquid solvent systems, Green Chem, vol.12, issue.2, p.63, 2010.

C. Yamane, T. Aoyagi, M. Ago, K. Sato, K. Okajima et al., Two Different Surface Properties of Regenerated Cellulose due to Structural Anisotropy, Polymer Journal, vol.38, issue.8, p.197, 2006.

T. Yamashiki, K. Kamide, K. Okajima, K. Kowsaka, T. Matsui et al., Some Characteristic Features of Dilute Aqueous Alkali Solutions of Specific Alkali Concentration (2.5 mol l -1 ) Which Possess Maximum Solubility Power against Cellulose, Polymer Journal, vol.20, issue.6, p.60, 1988.

D. Zhang, N. Zhang, P. Song, J. Hao, Y. Wan et al., Functionalized cellulose beads with three dimensional porous structure for rapid adsorption of active constituents from Pyrola incarnata, Carbohydr. Polym, vol.181, p.115, 2018.

J. Zhang, J. Wu, J. Yu, X. Zhang, J. He et al., Application of ionic liquids for dissolving cellulose and fabricating cellulosebased materials: state of the art and future trends, Materials Chemistry Frontiers, vol.1, issue.7, p.63, 2017.

J. Zhang, H. Zhang, J. Wu, J. Zhang, J. He et al., NMR spectroscopic studies of cellobiose solvation in EmimAc aimed to understand the dissolution mechanism of cellulose in ionic liquids, Phys. Chem. Chem. Phys, vol.12, issue.8, p.63, 2010.

S. Zhang, J. Feng, J. Feng, and Y. Jiang, Formation of enhanced gelatum using ethanol/water binary medium for fabricating chitosan aerogels with high specific surface area, Chemical Engineering Journal, vol.309, p.78, 2017.

B. Zhao, L. Greiner, and W. Leitner, Cellulose solubilities in carboxylate-based ionic liquids, RSC Adv, vol.2, issue.6, p.63, 2012.

Y. Zhao, X. Liu, J. Wang, and S. Zhang, Effects of Cationic Structure on Cellulose Dissolution in Ionic Liquids: A Molecular Dynamics Study, ChemPhysChem, vol.13, issue.13, p.63, 2012.

J. Zhou and L. Zhang, Solubility of Cellulose in NaOH/Urea Aqueous Solution, Polymer Journal, vol.32, issue.10, p.61, 2000.

S. Zhu, Y. Wu, Q. Chen, Z. Yu, C. Wang et al., Dissolution of cellulose with ionic liquids and its application: a mini-review, Green Chemistry, vol.8, issue.4, p.62, 2006.

P. Zugenmaier, Conformation and packing of various crystalline cellulose ®bers, Prog. Polym. Sci., P, vol.77, p.35, 2001.

, De nos jours, la production de bio-aérogels sous forme de monolithes est maîtrisée. Pour optimiser leur procédé de fabrication et pour répondre à des besoins spécifiques d'applications (pharmaceutiques, alimentaire, absorption ou adsorption, etc), les aérogels doivent avoir la forme de particules. Ce travail était focalisé sur la préparation et caractérisation de billes d'aérogels à base de cellulose et a été réalisé dans le cadre du projet Européen « Nanohybrids ». Deux objectifs principaux ont été atteints. Le premier était la préparation et la compréhension des propriétés de nouveaux matériaux, tout en diminuant leurs coûts de production. Deux types de matériaux poreux ont été produits et étudiés : ? Des xérogels à base de cellulose (en évitant le séchage sous CO2 supercritique), avec des propriétés comparables à celles de leurs homologues aérogels, RÉSUMÉ Les aérogels sont des matériaux ultra-poreux et nanostructurés aux possibilités d'applications variées. Une nouvelle génération d'aérogels à base de polysaccharides est aujourd'hui en plein essor : les bio-aérogels

, ? Des aérogels à base de pâte à papier. L'influence de chaque composant de la pâte (cellulose, hémicellulose, lignine) et de leur teneur sur la structure et les propriétés des aérogels a été évaluée

, Deux techniques ont été appliquées avec succès : ? Le "JetCutting" : des billes d'aérogels à base de cellulose et de pâte à papier, de taille variant de centaines de micromètres à quelques millimètres, dissout dans deux types solvants (NaOH-eau et liquides ioniques) ont été obtenus

. ?-l', émulsification : des particules d'aérogels de cellulose d'une dizaine de micromètres ont été préparé par le développement d'une nouvelle méthode d'émulsification-coagulation

. Mots-clés-bio-aérogels, These fast developing materials are particularly promising for their environmental friendliness and biocompatibility. Nowadays, the production of bio-aerogels in the form of monoliths is mastered. To optimize their manufacturing process and to meet specific application needs (pharmaceutical, food, absorption or adsorption, etc.), aerogels must be in the form of particles. This work focused on the preparation and characterization of cellulose aerogel beads and was conducted in the framework of the European project "Nanohybrids". Two main objectives were achieved. The first was the preparation and understanding of the properties of new materials while reducing their production costs. Two types of porous materials were produced and studied: ? Cellulose-based xerogels (obviating drying under supercritical CO2), Cellulose. Porosité. Particules. ABSTRACT Aerogels are ultra-porous and nanostructured materials with a wide range of applications. Bio-aerogels is a new generation of polysaccharide-based aerogels

?. Pulp-based and . Aerogels, The influence of each pulp component (cellulose, hemicellulose, lignin) and their content on the structure and properties of aerogels was assessed

, The second objective was the development of methods for shaping cellulose aerogels into beads of different sizes. Two techniques were successfully applied: ? JetCutting: aerogel beads based on cellulose and pulps, varying in size from hundreds of micrometres to a few millimetres

, Emulsification: cellulose aerogel particles of about few tens of micrometres were prepared by the development of a new method of emulsification-coagulation

, KEYWORDS Bio-aerogels. Cellulose. Porosity. Particles