Hydrogenation of C60 on alumina-supported nickel and thermal properties of C60H36

Abstract

Hydrogenation of C₆₀ was carried out in toluene using Ni/Al₂O₃ catalyst. C₆₀H₃₆ was obtained in the temperature range 150–250°C and the hydrogen pressure range 25–75 kgf cm^-2 (1 kgf=9.80665 N). Degradation of the fullerene giving lighter hydrocarbons was not observed under the experimental conditions. C₆₀ conversion was estimated from the decrease of absorbance of solution at 600 nm and compared with toluene conversion to methylcyclohexane. C₆₀ hydrogenation was faster than toluene hydrogenation. Thermogravimetry and differential thermal analysis of C₆₀H₃₆ were performed in air and compared with those of C₆₀, active carbon and diamond. C₆₀H₃₆ was partially oxidized at 277°C giving C₆₀H₃₆O_x (x=ca. 4.8) followed by combustion at 472°C. The temperature was much lower than that of C₆₀, of which the partial oxidation and the combustion were observed at 432 and 615°C, respectively. The number of oxygen atoms added was larger for C₆₀H₃₆ than for C₆₀. These results strongly suggest that C₆₀H₃₆ is more reactive for oxygen than C₆₀.