Formamide: Bungwe Lofufuza Limapereka Kujambula kwa Waste PET Pulasitiki Kuti Apange Formamide

Polyethylene terephthalate (PET), monga poliyesitala yofunikira ya thermoplastic, imakhala ndi chaka padziko lonse lapansi kupitilira matani 70 miliyoni ndipo imagwiritsidwa ntchito kwambiri popanga zakudya zatsiku ndi tsiku, nsalu, ndi magawo ena. Komabe, kuseri kwa kuchuluka kwakukulu kumeneku, pafupifupi 80% ya zinyalala za PET zimatayidwa kapena kutayidwa, zomwe zimapangitsa kuti chilengedwe chiwonongeke kwambiri ndikuwononga zinthu zambiri za carbon. Momwe mungakwaniritsire kubwezeretsanso zinyalala za PET zakhala vuto lalikulu lomwe likufuna kuti pakhale chitukuko chokhazikika padziko lonse lapansi.

Pakati pa matekinoloje omwe alipo kale, ukadaulo wa Photoreforming wakopa chidwi kwambiri chifukwa cha mawonekedwe ake obiriwira komanso ofatsa. Njira imeneyi imagwiritsa ntchito mphamvu ya dzuwa yoyera, yosaipitsa monga mphamvu yoyendetsera, imapanga mitundu yogwira ntchito ya redox mu situ pansi pa kutentha kozungulira ndi kukakamizidwa kuti athandize kutembenuka ndi kukweza mtengo kwa mapulasitiki a zinyalala. Komabe, zinthu zomwe zikuchitika masiku ano zojambula zithunzi nthawi zambiri zimakhala ndi zinthu zosavuta zomwe zimakhala ndi okosijeni monga formic acid ndi glycolic acid.

Posachedwapa, gulu lofufuza kuchokera ku Center for Photochemical Conversion and Synthesis ku bungwe ku China linaganiza zogwiritsa ntchito zinyalala za PET ndi ammonia monga magwero a kaboni ndi nayitrogeni, motero, kupanga formamide kudzera pa photocatalytic CN coupling reaction. Kuti izi zitheke, ofufuzawo adapanga chithunzithunzi cha Pt1Au/TiO2. Mu chothandizira, single-atomu Pt malo kusankha kulanda ma elekitironi photogenerated, pamene Au nanoparticles kulanda maenje photogenerated, kwambiri utithandize kulekana ndi kusamutsa dzuwa la photogenerated elekitironi-dzenje awiriawiri, potero kukulitsa ntchito photocatalytic. Mlingo wa kupanga formamide unafika pafupifupi 7.1 mmol gcat⁻¹ h⁻¹. Zoyeserera monga in-situ infrared spectroscopy ndi ma elekitironi paramagnetic resonance zidawulula njira yolumikizirana kwambiri: mabowo opangidwa ndi zithunzi nthawi imodzi amathira ethylene glycol ndi ammonia, kupanga ma aldehyde intermediates ndi amino radicals (·NH₂), omwe amalumikizana ndi CN kuti pamapeto pake apange mamide. Ntchitoyi sikuti imangoyambitsa njira yatsopano yosinthira pulasitiki yamtengo wapatali kwambiri, kukulitsa kuchuluka kwa zinthu zopangira PET, komanso imapereka njira yobiriwira, yotsika mtengo, komanso yodalirika yopangira kupanga zinthu zofunika kwambiri zomwe zimakhala ndi nayitrogeni monga mankhwala ndi mankhwala ophera tizilombo.

Zofukufuku zofananira zinasindikizidwa mu Angewandte Chemie International Edition pansi pa mutu wakuti "Photocatalytic Formamide Synthesis from Plastic Waste and Ammonia via CN Bond Construction Under Mild Conditions". Kafukufukuyu adalandira ndalama kuchokera kumapulojekiti othandizidwa ndi National Natural Science Foundation ya China, Joint Laboratory Fund for Novel Materials pakati pa Chinese Academy of Sciences ndi The University of Hong Kong, pakati pa ena.