Abordagem Circular para Transformação Catalítica de Olefinas Derivadas de Plástico Pirolisado em Produtos Oxigenados com Valor Acrescentado

The accumulation of plastics in the environment has triggered a global pollution crisis, which poses huge challenges both to Society and scientific community. Besides recognizing the importance of promoting environmental education actions to inform, alert and reduce the excessive plastic consumption, this team underscores the imperative need of creating new solutions to rethink plastic waste management, through the development of efficient strategies for chemical transformation of plastics into value-added products. Recently, there has been a significant investment in the development of efficient pyrolysis processes for transformation of polyolefins plastic into oils. However, while many industries have solved this problem, their utilization as fuel additives or lubricants is far from feasible due to the high instability of those olefins at high temperatures, combined with small chain size and low oxygen content, resulting in suboptimal octane ratings. In response to these challenges, the ECOXOPLAS project aims to go beyond the current state of the art by developing stable and reusable catalysts capable of promoting hydroformylation and epoxidation reactions on plastic-derived olefin oils, to increase their carbon-chain size and oxygen content, thereby transforming those into value-added products with a higher oxygen content. To enable the application of this technology and make a significant contribution to the reassessment of pyrolyzed plastics oils, crucial issues remain to be solved, being the goals of this proposal: i) To prepare active, robust and reusable heterogeneous metal catalysts CAT 1 (Rh, Ru, Co) for hydrofomylation and CAT 2 (Fe, Mn, Mo) for epoxidation (Scheme 1), or immobilized molecular catalysts CAT 3 (Rh, Ru, Co) for hydroformylation and CAT4 (Fe, Mn, Co, Ru) for epoxidation (Schemes 2-3), based on renewable P- or N-doped Biochar based supports. ii) To evaluate the P-based catalysts CAT 1 and 3 in hydroformylation of olefin plastics oils (batch and flow processes) aiming the selection of the best catalysts (Scheme 4). iii) To optimize the derivatization of aldehydes into highly stable and oxygenated products namely acetals, aldol products, alcohols and carboxylic acids, through sequential reactions, using batch and continuous-flow processes (Scheme 6) iv) To evaluate all the N-based catalysts CAT 2 and 4 in epoxidation of olefin plastics oils (batch and flow processes), to select the best catalysts (Scheme 5) v) To optimize the conversion of epoxides into highly stable and oxygenated products namely diols, hydroxyethers and hydroxyamines (batch and flow processes) through sequential reactions (Scheme 7). vi) To develop multi-gram flow sequential processes to transform the aldehydes and epoxides onto highly stable derivatives for industrial transposition to real applications as fuel additives and lubricants (Schemes 6-7). vii) To perform life cycle assessment (LCA) studies to analyze the overall process sustainability and circularity. Thus, the ultimate goal of ECOXOPLAS is to transform plastic waste into high-value oxygenated products, with high economic potential. It is important to emphasize the interest shown by the company BGW SA in the potential outcomes of this proposal. ECOXOPLAS not only demonstrates a worthy commitment to environmental sustainability but also positions itself as a driving force for positive economic growth and innovation in Portugal, particularly in Central region.