PROCESS FOR THE PRODUCTION OF A MATERIAL NANOCELULOSE NOT DERIVATIZED FROM A CELLULOSIC FIBROUS MATERIAL， USE OF THE PROCESS LIQUID and MATERIAL OF NON-AQUEOUS NANOCELULOSE NOT DERIVATIZED

A process for the production of a non-derivatized nanocellulose material from a cellulosic fibrous material， comprising the steps of providing a suspension of cellulosic fibrous material in a continuous phase of a non-aqueous process liquid comprising a swelling agent and a processing solvent;allowing the cellulosic fibrous material to swell such as to form a suspension of swollen cellulosic fibrous material in a continuous phase of non-aqueous process liquid;optionally refining said suspension of swollen cellulosic fibrous material in a continuous phase of non-aqueous process liquid to increase the fineness of the swollen cellulosic fibrous material;removing the swelling agent from the rocess liquid such as to form a suspension of cellulosic fibrous material in a continuous phase of processing solvent; subjecting the swollen and optionally refined cellulosic fibrous material to high-shear comminution such as to release of the non-derivatized nanocellulose material from the swollen and optionally refined cellulosic fibrous material and such as to form a dispersion of non-derivatized nanocellulose material in a continuous phase of a processing solvent; contacting the dispersion of non-derivatized nanocellulose material in a continuous phase of a processing solvent with a supercritical fluid such as to remove the processing solvent and isolate the non-derivatized nanocellulose material， wherein the supercritical fluid is preferably supercritical carbon dioxide or ammonia;characterized in that the swelling agent is a low- transition-temperature mixture (LTTM) and in particular a deep eutectic solvent and said low- transition-temperature mixture and in particular said deep eutectic solvent is soluble in the processing solvent and wherein the processing solvent is non-solubilizing for the cellulosic fibrous material and the non-derivatized nanocellulose material. A process for the production of a non-derivatized nanocellulose material from a cellulosic fibrous material， comprising the steps of providing a suspension of cellulosic fibrous material in a continuous phase of a non-aqueous process liquid comprising a swelling agent and a processing solvent;allowing the cellulosic fibrous material to swell such as to form a suspension of swollen cellulosic fibrous material in a continuous phase of non-aqueous process liquid;optionally refining said suspension of swollen cellulosic fibrous material in a continuous phase of non-aqueous process liquid to increase the fineness of the swollen cellulosic fibrous material;removing the swelling agent from the rocess liquid such as to form a suspension of cellulosic fibrous material in a continuous phase of processing solvent; subjecting the swollen and optionally refined cellulosic fibrous material to high-shear comminution such as to release of the non-derivatized nanocellulose material from the swollen and optionally refined cellulosic fibrous material and such as to form a dispersion of non-derivatized nanocellulose material in a continuous phase of a processing solvent; contacting the dispersion of non-derivatized nanocellulose material in a continuous phase of a processing solvent with a supercritical fluid such as to remove the processing solvent and isolate the non-derivatized nanocellulose material， wherein the supercritical fluid is preferably supercritical carbon dioxide or ammonia;characterized in that the swelling agent is a low- transition-temperature mixture (LTTM) and in particular a deep eutectic solvent and said low- transition-temperature mixture and in particular said deep eutectic solvent is soluble in the processing solvent and wherein the processing solvent is non-solubilizing for the cellulosic fibrous material and the non-derivatized nanocellulose material.