Direct Conversion of Polypropylene into Liquid Hydrocarbons on Carbon‐Supported Platinum Catalysts

Abstract

Efforts to selectively convert polypropylene (≈30 % of all plastic waste) have not been particularly successful. Typical distributions span from gas to solid products, highlighting a challenging cleavage control. Here, carbon‐supported platinum nanoparticles were designed for complete hydrocracking into liquid hydrocarbons (C5–C45). The metal and carrier phases operated synergistically. The cleavage activity depended on platinum and its rate rose with decreasing particle size. The carbon carrier controlled selectivity via hydrocarbon binding strength, which depended on the chain length and on the surface oxygen concentration. An optimal binding provided by carbons with high oxygen content promoted both adsorption of long chains and desorption of short products. This strategy achieved an unprecedented 80 % selectivity toward motor oil (C21–C45). Carbons exhibiting too strong binding (low oxygen content) hindered product desorption, while non‐binding materials (e. g., silica or alumina) did not promote plastic–Pt contact, leading in both cases to low performance. This work pioneers design guidelines in a key process towards a sustainable plastic economy.

Expanding Plastics Recycling Technologies: Chemical Aspects, Technology Status and Challenges

“…[889][890][891][892] Sadow and coworkers reported that PE can be converted into lubricants and waxes (Mw 200-1000 Da) over platinum supported on strontium titanate or mesoporous shell/Pt/silica at 250-300 °C in the presence of H2 (10-17 bar). [890][891] Moreover, platinum can be supported on carbon which catalyzes the conversion of PP into liquid hydrocarbons (C5-C45) 892 , or on WO3/ZrO2 and mixed with zeolites which catalyzes the production of liquid fuels and short-chain hydrocarbons from PE, PP or PS. 889 The synergistic effects between platinum and supports (carbon/metal oxides) or co-catalysts (zeolites) are vital in these processes.…”

Expanding plastics recycling technologies: chemical aspects, technology status and challenges

“…[871][872][873][874] Sadow and coworkers reported that PE can be converted into lubricants and waxes (Mw 200-1000 Da) over platinum supported on strontium titanate or mesoporous shell/Pt/silica at 250-300 °C in the presence of H2 (10-17 bar). [872][873] Moreover, platinum can be supported on carbon which catalyzes the conversion of PP into liquid hydrocarbons (C5-C45) 874 , or on WO3/ZrO2 and mixed with zeolites which catalyzes the production of liquid fuels and short-chain hydrocarbons from PE, PP or PS. 871 The synergistic effects between platinum and supports (carbon/metal oxides) or co-catalysts (zeolites) are vital in these processes.…”

Expanding Plastics Recycling Technologies: Chemical Aspects, Technology Status and Challenges

“…[870][871][872][873] Sadow and coworkers reported that PE can be converted into lubricants and waxes (Mw 200-1000 Da) over platinum supported on strontium titanate or mesoporous shell/Pt/silica at 250-300 °C in the presence of H2 (10-17 bar). [871][872] Moreover, platinum can be supported on carbon which catalyzes the conversion of PP into liquid hydrocarbons (C5-C45) 873 , or on WO3/ZrO2 and mixed with zeolites which catalyzes the production of liquid fuels and short-chain hydrocarbons from PE, PP or PS. 870 The synergistic effects between platinum and supports (carbon/metal oxides) or co-catalysts (zeolites) are vital in these processes.…”