Spheroidal micro silica has a large specific-surface. This makes it indispensable for the manufacture of composite materials: construction mixtures, paints, rubber, adsorbents, etc. In the process of studying the properties of dust formed in the production of silicon, it was established that practically all of the quartzite carried away in the form of a fine dust phase into the gas removal and gas cleaning system is represented by spheroidized micro- and nanoparticles of SiO2 with a carbon impurity that is invariably present also in the finely dispersed state. One of the ways to extract carbon and amorphous silicon oxide from the dust cyclone is flotation. As a result of flotation, 29% of the sand fraction, 40% of the foam product enrichedcarbon, and 31% of the chamber product enriched SiO2 were obtained. It is shown that the target nanofraction of amorphous silica from the chamber product after flotation can be extracted by electrocoagulation. The dependence of the mass of the coagulum on the current density on aluminum electrodes was obtained during electrocoagulation of the chamber product. It is established that under the action of current on the system under investigation, the metal of the cathode and the anode dissolve. The mechanism of electrocoagulation is shown. The chamber product is a stable finely dispersed SiO2 suspension with a pH of 8-9. Since the surface of the silica is hydrophilic, OH- is adsorbed on it and the surface of the dispersed particle is charged negatively. As a result of electrochemical and chemical dissolution of aluminum electrodes, the aluminum hydroxide formed has a positive charge. The different particles stick together, as a result of which their dimensions increase, coagulation takes place, and then precipitation occurs.Forcitation:Petrovskaya V.N., Kondrat’ev V.V., Petrovskiy A.A. Mechanism of electrocoagulation of chamber product after flotation of cyclone dust of silicon production. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 10. P. 68-74