The pyrolysis of polypropylene to polypropylene wax in a 1-L autoclave has been studied at low temperature. A four-lump kinetics model of pyrolysis of polypropylene to polypropylene wax, gaseous and liquid products is performed, and the kinetic parameters of the conversion of polypropylene into different products are determined. The total activation energy for the conversion of polypropylene was estimated to be 214 kJ mol −1 . The polypropylene wax obtained had a drop melting point of 121-150°C, and the weight average molecular was 7,419 g/mol. Fourier transform infrared analysis of the polypropylene wax showed that it is less branched and that its olefinic content is higher than that of commercial wax.

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A series of Cu-Fe-Co based catalysts prepared by co-impregnation method using different alkali additives was characterized by BET, XRD and FESEM-EDX and investigated under MAS from CO hydrogenation. The results showed that the catalyst Cu25Fe22Co3-Na3/SiO2 has the highest catalytic activity and selectivity of total alcohol and C5+OH. XRD and FESEM-EDX demonstrated the Na3 catalyst exhibited homogeneous distribution of elements and effective synergy effect between Cu and Fe components, thereby performed good catalytic performances for MAS from CO hydrogenation. The presence of a suitable content of alkali promoter was necessary for mixed alcohols synthesis from syngas.

The K/Cu-Zn catalyst has been synthesized by the co-precipitation method coupling with impregnation method and the catalytic performances for the reverse water gas shift (RWGS) reaction and mixed alcohols synthesis from CO2 hydrogenation have been investigated. The catalytic activity and product distribution depend strongly on reaction temperature, pressure, space velocity and the molar ratio of H2/CO2. These results indicated that the optimal conditions for CO2 hydrogenation over K/Cu-Zn catalyst were as follows: 350 K, 6.0 MPa, 5000 h-1 and H2/CO2 = 3.0, under which the selectivity of CO and mixed alcohols reach 84.27 wt% and 7.56 wt%, respectively. The outstanding performances for RWGS reaction and mixed alcohols synthesis of K/Cu-Zn catalyst can be due to the well dispersion of Cu active component.