Imbonakalo yeenguqu ezimbini ze-catalyst, kunye necandelo leqokobhe elisusiweyo ukubonisa ingaphakathi. Ingqukuva emhlophe imele iqokobhe lesilica, imingxuma yi pores. Iingqungquthela eziluhlaza ezikhanyayo zimela iindawo ze-catalytic, ezisekhohlo zincinci kakhulu kunezo zisekunene. Iintambo ezibomvu ezide zimele iintambo ze-polymer, kwaye iintambo ezimfutshane ziyimveliso emva kwe-catalysis. Zonke iintambo ezimfutshane ziyafana ngobukhulu, ezimele ukhetho olungaguquguqukiyo kuzo zonke iintlobo zecatalyst. Ukongeza, kukho amatyathanga amancinci amancinci aveliswa ziindawo ezincinci ze-catalyst kuba ukusabela kwenzeka ngokukhawuleza. Ikhredithi: Umfanekiso ngoncedo lwe-Argonne National Laboratory, iSebe lezaMandla lase-US
Itekhnoloji yePlastiki yokunyusa ibhayisekile iphuhliswa yi-catalyst esanda kuphuhliswa yokuqhekeza iiplastiki. Iqela lezazinzulu ezikhokelwa yi-Ames Laboratory izazinzulu zafumanisa i-catalyst yokuqala ye-inorganic ngo-2020 ukuba deconstruct iiplastiki polyolefin zibe iimolekyuli ezinokuthi zisetyenziswe ukwenza iimveliso ezixabiseke ngakumbi. Iqela ngoku liphuhlise kwaye liqinisekise isicwangciso sokukhawulezisa inguqu ngaphandle kokuncama iimveliso ezinqwenelekayo.
I-catalyst yayiyilwe nguWenyu Huang, isazinzulu kwiLebhu yase-Ames. Iqulethwe ngamasuntswana eplatinam axhaswa kwisiseko esiqinileyo sesilica kwaye ijikelezwe yigobolondo ye-silica eneepores ezifanayo ezibonelela ngokufikelela kwiindawo ezincedayo. Isixa esipheleleyo seplatinam esifunekayo sincinci kakhulu, nto leyo ibalulekile ngenxa yexabiso eliphezulu leplatinam kunye nokubonelela okunyiniweyo. Ngexesha lovavanyo lwe-deconstruction, amatyathanga e-polymer amade angena kwi-pores kwaye aqhagamshelane neendawo ze-catalytic, kwaye ke amatyathanga aqhekezwe abe ngamaqhekeza amancinci angeyonto yeplastiki (jonga umfanekiso ongentla ngeenkcukacha ezithe vetshe).
Ngokutsho kuka-Aaron Sadow, isazinzulu kwi-Ames Lab kunye nomlawuli we Iziko leNtsebenziswano yokuNyuswa kweePlastiki (iCOUP), iqela lenze iintlobo ezintathu ze-catalyst. Ukwahluka ngakunye kwakuneecores ezinobungakanani obufanayo kunye namaqokobhe athambileyo, kodwa iidayamitha ezahlukeneyo zamasuntswana eplatinam, ukusuka kwi-1.7 ukuya kwi-2.9 ukuya ku-5.0 nm.
Abaphandi bacinga ukuba ukuhlukana kweplatinum ubukhulu becala kuya kuchaphazela ubude bemixokelelwane yemveliso, ngoko ke iiplatinum ezinkulu ziza kwenza amatyathanga amade kwaye amancinci angenza amakhonkco amafutshane. Noko ke, eli qela lafumanisa ukuba ubude bamatyathanga emveliso babulingana kuzo zontathu ii-catalysts.
"Kwincwadi, ukhetho lwe-carbon-carbon bond cleavage reactions luhlala luhluka kunye nobukhulu beplatinum nanoparticles. Ngokubeka iplatinam emazantsi ee pores, sibone into eyahlukileyo,” utshilo uSadow.
Endaweni yoko, isantya apho amatyathanga aqhekezwe abe ziimolekyuli ezincinci zahlukile kwizinto ezintathu ezibangela ukuba kube lula. Amasuntswana eplatinam amakhulu aye asabela ngekhonkco elide lepholima ngokucotha ngakumbi ngelixa amancinane asabela ngokukhawuleza. Oku kunyuka kwesantya kunokubangelwa kwipesenti ephezulu yeendawo ezinqamlekileyo kunye nekona yeplatinam kwiindawo ezincinci ze-nanoparticles. Ezi ndawo zisebenza ngakumbi ekucaleni ikhonkco lepolymer kuneplatinam ebekwe ebusweni bamaqhekeza.
NgokukaSadow, iziphumo zibalulekile kuba zibonisa ukuba umsebenzi unokulungiswa ngokuzimeleyo ekukhetheni kwezi mpendulo. "Ngoku, siqinisekile ukuba sinokwenza into esebenzayo ngakumbi enokuhlafuna ipolymer ngokukhawuleza, ngelixa sisebenzisa iiparamitha ze-catalyst structural parameters ukucofa ubude bekhonkco lemveliso ethile," utshilo.
U-Huang wachaza ukuba olu hlobo lwe-molecule enkulu yokuphinda isebenze kwii-catalysts ezinama-porous ngokubanzi azifundwanga ngokubanzi. Ke, uphando lubalulekile ekuqondeni isayensi esisiseko kunye nendlela eqhuba ngayo ukunyusa iiplastiki.
“Kufuneka siyiqonde ngakumbi le nkqubo kuba sisafunda izinto ezintsha mihla le. Sijonga ezinye iiparamitha esinokuziculela ukunyusa izinga lemveliso kwaye sitshintshe ukuhanjiswa kwemveliso, ”utshilo uHuang. "Zininzi izinto ezintsha kuluhlu lwethu ezilindele ukuba sizifumane."
Isalathiso: "Ii-Nanoparticles eziLawulwayo ngobungakanani obufakwe kwi-Architecture ye-Mesoporous Ekhokelela kwi-Hydrogenolysis esebenzayo kunye neKhethekileyo ye-Polyolefins" nguXun Wu, Akalanka Tennakoon, Ryan Yappert, Michaela Esveld, Magali S. Ferrandon, Ryan A. Hackler, Anne M. LaPointe, Andreas Heyden, Massimiliano Delferro, Baron Peters, Aaron D. Sadow kunye noWenyu Huang, nge-23 kaFebruwari 2022, Umbhalo we-American Chemical Society.
I-DOI: 10.1021/jacs.1c11694
Uphando luqhutywe yi-Institute for Cooperative Upcycling of Plastics (iCOUP), ekhokelwa yi-Ames Laboratory. I-iCOUP yi-Energy Frontier Research Centre equka izazinzulu ezivela kwi-Ames Laboratory, i-Argonne National Laboratory, i-UC Santa Barbara, iYunivesithi yaseMzantsi Carolina, iYunivesithi yaseCornell, University, kunye neYunivesithi yase-Illinois Urbana-Champaign.
