Patent Number: HK30085576 Patent Type: Hong Kong Short Term Patent (granted 2023) Title: Method for producing pyrolysis oil and carbon powder from waste plastic pyrolysis This invention provides a catalytic pyrolysis method that converts mixed waste plastics (PP, PS, HDPE, LDPE) into high yield pyrolysis oil (~75%) and carbon powder. The process operates at 550–600°C under slightly negative pressure, using standard commercially available zeolite based catalysts. The light to heavy oil ratio is adjustable by catalyst selection. The method has been pilot proven on a 3 ton/batch unit with over 200 cumulative operating hours.