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We have developed an easy route to prepare (nano-ZrO₂,nano-ZrC_x)@C composites with varying ZrO₂/ZrC_x content. The process consists of preparing a zirconium-loaded, iminodiacetate-functionalized styrene-divinylbenzene (STY-DVB) copolymer, and its subsequent carbonization in a tube furnace and/or a thermal plasma reactor. Depending on the zirconium salt used (zirconyl chloride, zirconyl nitrate or zirconium (IV) sulfate) in the Zr loading, the Zr-loaded resins resulted in ZrO₂@C pre-pyrolizates with C to Zr molar ratios of 5.8, 6.8 and 6.60. This carbon surplus is sufficient for the partial or even complete reduction of ZrO₂ into ZrC_0.58 at 1400 °C. The reaction products also contain 5 to 55 mass% residual free carbon. The plasma processing of the ZrO₂@C composite formed at 1000 °C in a tube furnace led to ZrC_0.94@C composites. The transformation of amorphous carbon content during the plasma treatment strongly depended on the atmosphere (He or H₂) in the reactor and the anion type of the Zr salt. In the presence of He, amorphous carbon could be completely transformed into graphite. In the presence of H₂, amorphous carbon and graphite were found at roughly the same ratio. No ZrO₂ could be detected in the plasma-treated samples, whilst different ZrO₂ polymorphs were found in the samples prepared in the tube furnace, depending on the synthesis conditions.