To efficiently and economically decompose/remove nitrogenous compounds and/or chlorinated compounds from a decomposed oil of waste plastics to prepare a refined oil by hydrogenating the decomposed oil in the presence of a catalyst.
A decomposed oil that is a decomposition product of waste plastics is hydrogenated in the presence of a catalyst, so that at least either of nitrogenous compounds or chlorinated compounds contained in the oil are decomposed/removed to produce a refined oil. In the above treatment, it is desired that the treating temperature is 200-600°C, the catalyst used is a transition-metal catalyst, and the amount of the catalyst used is 5-500g per 1kg of the cracked oil. The refined oil is produced efficiently and economically from the decomposed oil of waste plastics. Further, by subjecting the refined oil to a steam cracking treatment, 1-olefins such as ethylene and propylene and conjugated diolefins such as butadiene can be reclaimed in purifies usable as petrochemical raw materials.
SHIMAMOTO KENJI
HIROWATARI NORIYUKI
