THE EFFECT OF MULTISTAGE COMPLEX PURIFICATION ON THE COMPOSITION AND PHYSICOCHEMICAL PROPERTIES OF INDUSTRIAL PYROLYSIS SOOT

The article investigates a comprehensive purification method for soot produced during the oxidative pyrolysis of natural gas at JSC “Navoiyazot,” aimed at preparing it for use as a carbon pigment in electrographic toners. The process consists of extraction with a toluene–acetone mixture, demineralization using a 10% HCl solution, and vacuum thermal treatment at 350 °C and a pressure of 10⁻² MPa. As a result of purification, the ash content decreases from 3.15% to 0.18%, while the proportion of resinous substances decreases from 4.80% to below 0.05%. The specific surface area increases from 62 to 118 m²/g, and the specific volume electrical resistivity rises from 1.8 × 10² to 1.2 × 10³ Ω·cm. Stage-by-stage analysis shows that extraction primarily reduces resinous substances, while acid treatment is mainly responsible for removing mineral impurities. The results provide a basis for evaluating the purified soot in subsequent functional tests as a toner pigment.