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Carbon fiber reinforced polymers (CFRPs, or composites) are increasingly replacing traditional manufacturing materials used in the automobile, aerospace, and energy sectors. With this shift, it is vital to develop end-of-life processes for CFRPs that retain the value of both the carbon fibers and the polymer matrix. Here we demonstrate a strategy to upcycle pre- and post-con- sumer polystyrene-containing CFRPs, crosslinked with unsaturated polyesters or vinyl esters, to benzoic acid. The thermoset matrix is upgraded via biocatalysis utilizing an engineered strain of the filamentous fungus Aspergillus nidulans, which gives access to valuable secondary metabolites in high yields, exemplified here by (2Z,4Z,6E)-octa-2,4,6-trienoic acid. Reactions are engineered to preserve the carbon fibers, with much of their sizing, so that the isolated carbon fiber plies are manufactured into new composite coupons that exhibit mechanical properties comparable to virgin manufacturing substrates. In sum, this represents the first system to reclaim high value from both the fiber fabric and polymer matrix of a CFRP. 

Polystyrene (PS) is one of the most used, yet infrequently recycled plastics. Although manufactured on the scale of 300 million tons per year globally, current approaches toward PS degradation are energy- and carbon-inefficient, slow, and/or lim- ited in the value that they reclaim. We recently reported a scalable process to degrade post-consumer polyethylene-containing waste streams into carboxylic diacids. Engineered fungal strains then upgrade these diacids biosynthetically to synthesize pharmacologi- cally active secondary metabolites. Herein, we apply a similar reaction to rapidly convert PS to benzoic acid in high yield. Engi- neered strains of the filamentous fungus Aspergillus nidulans then biosynthetically upgrade PS-derived crude benzoic acid to the structurally diverse secondary metabolites ergothioneine, pleuromutilin, and mutilin. Further, we expand the catalog of plastic- derived products to include spores of the industrially relevant biocontrol agent Aspergillus flavus Af36 from crude PS-derived ben- zoic acid. 

Abstract. Atmospheric non-methane hydrocarbons (NMHCs) play an important role in theformation of secondary organic aerosols and ozone. After a multidecadalglobal decline in atmospheric mole fractions of ethane and propane – themost abundant atmospheric NMHCs – previous work has shown a reversal ofthis trend with increasing atmospheric abundances from 2009 to 2015 in theNorthern Hemisphere. These concentration increases were attributed to theunprecedented growth in oil and natural gas (O&NG) production in NorthAmerica. Here, we supplement this trend analysis building on the long-term(2008–2010; 2012–2020) high-resolution (∼3 h) record ofambient air C2–C7 NMHCs from in situ measurements at the GreenlandEnvironmental Observatory at Summit station (GEOSummit, 72.58 ∘ N,38.48 ∘ W; 3210 m above sea level). We confirm previous findingsthat the ethane mole fraction significantly increased by +69.0 [+47.4,+73.2; 95 % confidence interval] ppt yr−1 from January 2010 toDecember 2014. Subsequent measurements, however, reveal a significantdecrease by −58.4 [−64.1, −48.9] ppt yr−1 from January 2015 to December2018. A similar reversal is found for propane. The upturn observed after2019 suggests, however, that the pause in the growth of atmospheric ethaneand propane might only have been temporary. Discrete samples collected atother northern hemispheric baseline sites under the umbrella of the NOAAcooperative global air sampling network show a similar decrease in 2015–2018and suggest a hemispheric pattern. Here, we further discuss the potentialcontribution of biomass burning and O&NG emissions (the main sources ofethane and propane) and conclude that O&NG activities likely played arole in these recent changes. This study highlights the crucial need forbetter constrained emission inventories.