I-Formamide: Iziko loPhando liCebisa ukuTshintsho lweNkunkuma yePlastiki yePET ukuze kuveliswe iFormamide

I-Polyethylene terephthalate (PET), njenge-polyester ebalulekileyo ye-thermoplastic, inemveliso yonyaka yehlabathi edlula iitoni ze-70 yezigidi kwaye isetyenziswa ngokubanzi ekupakishweni kokutya kwemihla ngemihla, iingubo, kunye nezinye iindawo. Nangona kunjalo, emva kwalo mthamo mkhulu wemveliso, malunga ne-80% yenkunkuma ye-PET ilahlwa ngokungakhethiyo okanye ifakwe kumhlaba, ibangela ungcoliseko olumandla lwendalo kwaye ikhokelele kwinkcitho yemithombo yekhabhoni eninzi. Indlela yokuphumeza ukurisayikilishwa kwenkunkuma ye-PET ibe ngumngeni onzima ofuna impumelelo kuphuhliso oluzinzileyo lwehlabathi.

Phakathi kwetekhnoloji ekhoyo yokuphinda isetyenziswe, itekhnoloji yefotoreforming ifumene ingqwalasela ebalulekileyo ngenxa yeempawu zayo eziluhlaza kunye nezithambileyo. Obu buchule busebenzisa amandla elanga acocekileyo, angangcolisiyo njengamandla okuqhuba, kuvelisa iindidi ezisebenzayo ze-redox kwindawo ephantsi kobushushu obukuleyo kunye noxinzelelo lokuququzelela uguqulo kunye nophuculo olongezelelekileyo lwenkunkuma yeplastiki. Nangona kunjalo, iimveliso zenkqubo ye-photoreforming yangoku zilinganiselwe kwiikhompawundi ezilula ezine-oksijini ezifana ne-fomic acid kunye ne-glycolic acid.

Kutshanje, iqela lophando elivela kwiZiko le-Photochemical Conversion kunye ne-Synthesis kwiziko lase-China licebise ukusebenzisa inkunkuma ye-PET kunye ne-ammonia njengemithombo ye-carbon kunye ne-nitrogen, ngokulandelanayo, ukuvelisa i-formamide nge-photocatalytic ye-CN yokudibanisa i-coupling reaction. Ukuza kuthi ga ngoku, abaphandi bayila i-photocatalyst ye-Pt1Au/TiO2. Kule catalyst, iisayithi ze-Pt ze-atom enye zithatha ngokukhethiweyo ii-electron ezenziwe ngeefoto, ngelixa i-Au nanoparticles ibamba imingxuma eyenziwe ngefoto, iphucula kakhulu ukwahlula kunye nokuhanjiswa ngokufanelekileyo kwee-photogenerated electron-hole pairs, ngaloo ndlela inyusa umsebenzi we-photocatalytic. Umyinge wemveliso yeformamide ufikelele malunga ne-7.1 mmol gcat⁻¹ h⁻¹. Imilingo efana ne-in-situ ye-infrared spectroscopy kunye ne-electron paramagnetic resonance ibonise indlela yokusabela e-radical-mediated: imingxunya eyenziwe ngeefoto ngaxeshanye i-oxidize i-ethylene glycol kunye ne-ammonia, ivelisa i-aldehyde intermediates kunye ne-amino radicals (·NH₂), ezityhubela ukudibanisa kwe-CN ukuze ekugqibeleni zenze i-formamamide. Lo msebenzi awukho nje uvulindlela indlela entsha yokuguqulwa kwexabiso eliphezulu leeplastiki zenkunkuma, ukutyebisa i-spectrum ye-PET imveliso yokuphucula, kodwa inika kwakhona isicwangciso esiluhlaza, esinoqoqosho ngakumbi, kunye nesithembisayo sokwenziwa kokuveliswa kwezinto ezibalulekileyo ze-nitrogen eziqulethe izinto ezifana namayeza kunye ne-pesticides.

Iziphumo zophando ezinxulumene nazo zipapashwe kwi-Angewandte Chemie International Edition phantsi kwesihloko esithi "Photocatalytic Formamide Synthesis evela kwiNkunkuma yePlastiki kunye ne-ammonia ngokusebenzisa i-CN Bond Construction phantsi kweeMeko eziPhakamileyo". Uphando lufumene inkxaso-mali kwiiprojekthi ezixhaswa yiNational Natural Science Foundation yaseTshayina, iNgxowa-mali yeLabhoratri edibeneyo yeZibonelelo zeNoveli phakathi kwe-Academy yaseTshayina yeSayensi kunye neYunivesithi yaseHong Kong, phakathi kweminye imithombo.