The purpose of this paper was the studying of hydrodynamic cavitation effect on physical properties of carbonaceous material ‑ heat-treated cellulose. The heat-treated cellulose powders have been investigated by the method of X-ray phase analysis (XPA). Hence it was possible to obtain nanofluid ‑ a water suspension with the features characteristic of weak water suspension of fulleroids as a result of rather short cavitation processing of the weak water suspension of heat-treated cellulose, nanofluid is very perspective for industrial technologies.