Review on marine plastic pyrolysis oil: Turning pollution into a maritime fuel

Marine litter, predominantly plastic waste, represents both an escalating environmental crisis and a potential resource for sustainable fuel production. This review offers the first comprehensive assessment of using marine litter as a feedstock for pyrolysis to generate alternative fuels for the maritime sector. Among various litter types, beach and floating plastics are identified as the most suitable for pyrolysis, given their accessibility and high plastic content, while seafloor litter presents additional collection and pretreatment challenges. Literature indicates that pyrolysis can yield 45 %–60 % oil from plastic-rich waste, requiring minimal upgrading to meet marine fuel standards. The resulting marine plastic-derived pyrolysis oil demonstrates high compatibility with existing maritime infrastructure, allowing for seamless blending with conventional fuels. However, limitations such as restricted production capacity and the fossil origin of plastic suggest that marine plastic-derived pyrolysis oil should be considered a transitional solution. This work uniquely proposes the integration of pyrolysis units within port reception facilities as a strategic and efficient approach to manage marine litter and produce low-carbon maritime fuels. Despite technical and logistical challenges, marine litter pyrolysis shows promising potential as a complementary pathway for both ocean cleanup and low-carbon fuel transition in the maritime sector. • Marine plastic waste yields 45 %–60% oil via pyrolysis, with little upgrading needed. • Plastic pyrolysis oil suits existing marine fuel systems without major changes. • Ports are ideal hubs for pyrolysis units in marine litter-to-fuel conversion chains. • Proposes a novel route for marine litter mitigation through fuel substitution. • Presents new insights, challenges and policy aspects of marine plastic pyrolysis.