Molten plastics are characterised with high viscosity and low thermal conductivity. Applying falling film pyrolysis reactor to deal with waste plastics can not only improve heat transfer efficiency

but also solve the flow problem. In this work

the pyrolysis process of molten polypropylene (PP) in a vertical falling film reactor is experimentally studied

and the influence of heating temperature on pyrolysis products is discussed. It has been found that with the temperature increases from 550℃ to 625℃

the yield of pyrolysis oil decreases from 74.4 wt% (±2.2 wt%) to 53.5 wt% (±1.3 wt%). The major compositions of the pyrolysis oil are C

9

C

12

and C

18

and β-scission reactions are predominant. The content of the light fraction C

6

-C

12

of pyrolysis oil is 69.7 wt%. Compared with other pyrolysis reactors

the yield of oil from vertical falling film pyrolysis reactor is slightly higher than that from tubular reactor

equal to that from rotary kiln reactor

and slightly lower than that in medium fluidised-bed reactor.