Cov khib nyiab yas yog qhov teeb meem zoo li nonws ua dej nyabhauv qee qhov ntawm lub ntiaj teb.Raws li cov yas polymers tsis yooj yim decompose, cov pa phem yas tuaj yeem txhaws tag nrho cov dej ntws.Yog hais tias nws mus txog lub hiav txwv nws xaus rau hauv lojfloating khib nyiab thaj ua rau thaj.

Hauv kev sib tw los daws cov teeb meem thoob ntiaj teb ntawm cov pa phem yas, cov kws tshawb fawb tau tsim cov yas degradable uas tawg tom qab raug tshav ntuj thiab huab cua rau ib lub lis piam - ib qho kev txhim kho loj heev nyob rau xyoo caum, lossis txawm ntau pua xyoo, nws tuaj yeem siv rau qee cov yas niaj hnub. cov khoom kom decompose.

Hauvib daim ntawv luam tawmNyob rau hauv phau ntawv Journal of the American Chemical Society (JACS), cov kws tshawb fawb tau piav qhia txog lawv cov tshiab ib puag ncig degradable yas uas tawg nyob rau hauv tshav ntuj mus rau hauv succinic acid, ib txwm tshwm sim tsis muaj tshuaj lom me me molecule uas tsis tawm microplastic tawg nyob rau hauv ib puag ncig.

Cov kws tshawb fawb siv nuclear magnetic resonance (NMR) thiab huab hwm coj spectroscopy chemical characterization los qhia lawv cov kev tshawb pom ntawm cov yas, roj av-raws li polymer.

Bio-based?Rov ua dua?Biodegradable?Koj phau ntawv qhia rau cov yas ruaj khov

Nrog kev ruaj khov siab ntawm txhua tus txheej txheem thiab thev naus laus zis nrawm nrawm, lub ntiaj teb ntawm cov yas hloov pauv.Nov yog yam koj yuav tsum paub txog cov ntaub ntawv yas niaj hnub no - thiab qee zaum cov lus tsis meej pem,

Cov khib nyiab yas tau dhau los ua kev txhawj xeeb thoob ntiaj teb.Ze li plaub puas lab tons ntawm nws raug tsim tawm thoob ntiaj teb txhua xyoo, thaum79 feem pua ​​​​ntawm tag nrho cov pov tseg yas uas tau tsim tau xaus rau hauv qhov chaw pov tseg lossis cov khib nyiab hauv ib puag ncig ntuj.

Tab sis dab tsi txog cov yas tshiab, ruaj khov dua - lawv puas yuav pab peb daws qhov kev sib tw pov tseg yas?Cov ntsiab lus bio-based, biodegradable lossis recyclable plastics txhais tau li cas, thiab lawv yuav pab tau peb li cas kom ua tiav cov hom phiaj kev ruaj ntseg thiab txo qis qhov xav tau ntawm cov roj crude hauv plastics ntau lawm?

Peb yuav coj koj los ntawm qee cov ntsiab lus feem ntau cuam tshuam nrog cov yas ruaj khov thiab nthuav tawm qhov tseeb tom qab txhua tus.

Bioplastics - yas uas yog bio-based lossis biodegradable los yog ob qho tib si

Bioplastics yog ib lo lus uas siv los hais txog cov yas uas yog bio-based, biodegradable, los yog haum rau ob qho tib si.

Nyob rau hauv sib piv rau cov tsoos plastics ua los ntawm fossil-based feedstock,bio-based plastics yog tag nrho lossis ib nrab ua los ntawm cov khoom siv txuas ntxivtau los ntawm biomass.Feem ntau siv cov khoom siv raw los tsim cov khoom siv txuas ntxiv mus rau cov khoom siv yas xws li pob kws stalks, qab zib stems thiab cellulose, thiab ntxiv ntau cov roj thiab cov rog los ntawm cov khoom siv txuas ntxiv.Cov ntsiab lus 'bioplastics' thiab 'bio-based plastics' feem ntau siv sib hloov los ntawm cov neeg nyob hauv tab sis lawv tsis txhais tau tias tib yam.

Biodegradable plasticsyog cov yas nrog cov qauv tshiab molecular uas tuaj yeem decomposed los ntawm cov kab mob thaum kawg ntawm lawv lub neej nyob rau hauv tej yam kev mob.Tsis yog txhua yam bio-based plastics yog biodegradable thaum qee cov yas ua los ntawm fossil fuels tiag tiag.

Bio-based - plastics uas muaj cov khoom tsim los ntawm biomass

Cov yas uas muaj bio-raws li yog ib feem los yog tag nrho ua los ntawm cov khoom uas tau tsim los ntawm biomass es tsis txhob fossil-raws li raw cov ntaub ntawv.Qee qhov biodegradable tab sis lwm tus tsis yog.

Hauv 2018, 2.61 lab tons ntawm bio-based plastics tau tsim tawm thoob ntiaj teb,Raws li lub koom haum rau Bioplastics thiab Biocomposites (IfBB).Tab sis qhov ntawd tseem tsuas yog tsawg dua 1% ntawm kev lag luam yas thoob ntiaj teb.Raws li kev thov rau cov yas txuas ntxiv zuj zus, yog li qhov kev thov rau cov kev daws teeb meem plastics ntau dua.Cov khoom siv fossil-raws li cov yas tuaj yeem hloov tau nrog cov yas tso rau hauv - qhov sib npaug ntawm bio-based.Qhov no tuaj yeem pab txo qis cov pa roj carbon hneev taw ntawm cov khoom kawg thaum lwm tus yam ntxwv ntawm cov khoom - nws cov kav ntev lossis rov ua dua tshiab - piv txwv li, nyob twj ywm tib yam.

Polyhydroxyalkanoate los yog PHA, yog ib hom biodegradable bio-raws li yas, tam sim no siv los ua ntim thiab fwj, piv txwv li.Nws yogtsim los ntawm kev lag luam fermentation thaum qee cov kab mob tau noj qab zib lossis roglos ntawm feedstocks xws libeets, qab zib cane, pob kws los yog zaub roj.Tab sis tsis xav tau byproducts,xws li pov tseg cov roj ua noj lossis cov kua nplaum uas nyob tom qab kev tsim khoom qab zib, tuaj yeem siv los ua lwm yam khoom noj, tso tawm cov qoob loo zaub mov rau lwm yam kev siv.

Raws li kev thov rau cov yas txuas ntxiv zuj zus, ntau yam ntawm bio-based plastics tau nkag mus rau hauv kev ua lag luam thiab yuav tsum tau siv ntau ntxiv los ua lwm txoj hauv kev.

-

Qee cov bio-raws li plastics, xws li, poob hauv plastics muaj cov qauv tshuaj zoo tib yam thiab cov khoom siv rau cov khoom siv niaj hnub.Cov plastics no tsis yog biodegradable, thiab lawv feem ntau siv rau hauv cov ntawv thov uas ua haujlwm ntev yog qhov xav tau.

Bio-based PET, uas yog ib feem ua los ntawm cov organic compound ethylene glycol pom nyob rau hauv cov nroj tsuag, yog siv nyob rau hauv ntau yam khoom xws lifwj, tsheb interiors thiab electronics.Raws li cov neeg siv khoom xav tau ntau dua cov yas kom ruaj khov,Kev ua lag luam rau cov yas no yuav tsum loj hlob los ntawm 10.8% los ntawm 2018 txog 2024, sib xyaw ua ke txhua xyoo.

Bio-based polypropylene (PP) yog lwm cov yas ntim uas tuaj yeem siv los ua cov khoom xws li cov rooj zaum, ntim thiab ntaub pua plag.Thaum kawg ntawm 2018,Kev lag luam nplai kev tsim khoom ntawm bio-based PP tau tshwm sim thawj zaug,ua los ntawm cov khoom pov tseg thiab cov roj seem, xws li cov roj ua noj.

Biodegradable - yas uas decomposes nyob rau hauv tej yam kev mob

Yog hais tias cov yas yog biodegradable, nws txhais tau hais tias nws muaj peev xwm mus decomposition nyob rau hauv ib puag ncig tej yam kev mob thiab thaum nyob rau hauv kev sib cuag nrog tej kab mob los yog microbes - tig nws mus rau hauv dej, biomass thiab carbon dioxide, los yog methane, nyob ntawm seb aerobic los yog anaerobic tej yam kev mob.Biodegradation tsis yog qhov qhia txog cov ntsiab lus bio-based;Hloov chaw, nws txuas nrog cov qauv molecular ntawm cov yas.Txawm hais tias feem ntau biodegradable plastics yog bio-based,Qee cov biodegradable plastics yog tsim los ntawm cov roj fossil raws cov khoom noj.

Lub sij hawm biodegradable yog tsis meej vim nws tsisqhia txog lub sijhawmlos yog ib puag ncig rau decomposition.Feem ntau cov yas, txawm tias tsis yog biodegradable, yuav degrade yog tias lawv muab sijhawm txaus, piv txwv li ntau pua xyoo.Lawv yuav tawg mus rau hauv cov khoom me me uas tuaj yeem pom tsis tau ntawm tib neeg lub qhov muag, tab sis nyob twj ywm tam sim no ua microplastics hauv ib puag ncig peb.Nyob rau hauv sib piv, feem ntau biodegradable plastics yuav biodegrade rau CO2, dej thiab biomass yog tias lawv muab sijhawm txaus.nyob rau hauv tej yam kev mob tshwj xeeb.Nws yog qhia tiascov lus qhia ntxawsTxog ntev npaum li cas cov yas siv rau biodegrade, qib ntawm biodegradation thiab cov xwm txheej yuav tsum tau muab los ntsuas nws cov ntaub ntawv pov thawj ib puag ncig zoo dua.Compostable yas, ib hom biodegradable yas, yooj yim rau kev ntsuam xyuas vim nws yuav tsum tau ua raws li cov qauv kev cai kom tau txais daim ntawv lo.

Compostable - ib hom biodegradable yas

Compostable yas yog ib qho ntawm cov yas biodegradable.Nyob rau hauv cov xwm txheej composting, nws tau tawg los ntawm microbes rau hauv CO2, dej thiab biomass.

Rau cov yas kom tau ntawv pov thawj raws li compostable, nws yuav tsum ua tau raws li cov qauv.Hauv Tebchaws Europe, qhov ntawd txhais tau tias hauv alub sij hawm ntawm 12 lub lis piam, 90% ntawm cov yas yuav tsum decompose rau hauv fragments tsawg dua 2 hlinyob rau hauv loj nyob rau hauv kev tswj tej yam kev mob.Nws yuav tsum muaj qib qis ntawm cov hlau hnyav kom nws tsis ua mob rau cov av.

Compostable plasticsyuav tsum tau xa mus rau ib qho chaw ua lag luam uas siv cov cua sov thiab cov av noonyob rau hauv thiaj li yuav xyuas kom meej degradation.PBAT, piv txwv li, yog fossil feedstock raws li polymer uas yog siv los ua cov organic pov tseg hnab, khob pov tseg thiab ntim zaj duab xis thiab yog biodegradable nyob rau hauv composting nroj tsuag.

Yas uas tawg nyob rau hauv qhov chaw qhib xws li hauv tsev compost heaps feem ntau nyuaj ua.Piv txwv li, PHAs haum rau daim nqi tab sis tsis tau siv dav txij li thaumlawv kim heev los tsim thiab cov txheej txheem qeeb thiab nyuaj rau scale.Txawm li cas los xij, chemists tau ua haujlwm los txhim kho qhov no, piv txwv li los ntawm kev sivib tug tshiab tshuaj catalyst- ib yam khoom uas pab nce tus nqi ntawm cov tshuaj tiv thaiv.

Recyclable - xa cov yas siv rau hauv cov khoom tshiab los ntawm kev siv tshuab lossis tshuaj

Yog tias cov yas rov ua dua tshiab, nws txhais tau hais tias nws tuaj yeem rov ua dua ntawm cov nroj tsuag kev lag luam thiab hloov mus ua lwm yam khoom siv.Ob peb hom ntawm cov pa yas tuaj yeem rov ua dua tshiab - hom kev rov ua dua tshiab.Tab sis thawj lub ntiaj teb kev tsom xam ntawm tag nrho cov pov tseg yas puas tau tsimpom tias tsuas yog 9% ntawm cov yas tau rov ua dua tshiab txij li cov khoom siv tau pib tsim tawm txog rau xyoo dhau los.

Mechanical recyclingNws suav nrog shredding thiab melting yas pov tseg thiab tig mus rau hauv pellets.Cov pellets no ces siv los ua raw khoom los ua cov khoom tshiab.Yas zoo deteriorates thaum lub sij hawm tus txheej txheem;yog li ntawd ib daim ntawm yastsuas tuaj yeem rov siv dua ib zaug xwbua ntej nws tsis haum raws li raw khoom.Cov yas tshiab, lossis 'virgin yas', yog li ntawd feem ntau sib xyaw nrog cov yas siv dua ua ntej nws hloov mus rau hauv cov khoom tshiab los pab kom ncav cuag qhov xav tau ntawm qhov zoo.Txawm li ntawd los, mechanically recycled plastics tsis haum rau txhua lub hom phiaj.

Cov yas siv tshuaj siv tau tuaj yeem hloov cov roj ntsha pob txha raws li cov khoom siv raw hauv kev tsim cov yas tshiab

-

Tshuaj siv dua tshiab, uas yog cov yas tau hloov rov qab rau hauv cov tsev thaiv thiab tom qab ntawd ua tiav rau hauv cov khoom siv zoo nkauj zoo nkauj rau cov yas tshiab thiab cov tshuaj, yog ib tsev neeg tshiab ntawm cov txheej txheem uas tam sim no tau txais lub zog.Nws feem ntau cuam tshuam nrog cov catalysts thiab / lossis kub siab heev los rhuav tshem cov yas thiabtuaj yeem siv rau ntau yam khoom pov tseg yas piv rau cov khoom siv rov ua dua tshiab.Piv txwv li, cov yeeb yaj kiab yas uas muaj ntau txheej txheej lossis qee yam kab mob tsis tuaj yeem feem ntau yog siv los ua cov khoom siv rov ua dua tshiab tab sis tuaj yeem siv tshuaj lom neeg.

Cov khoom siv raw uas tsim los ntawm cov pov tseg yas hauv cov txheej txheem chemical recycling tuaj yeem siv rauhloov virgin crude roj raws li raw cov ntaub ntawv nyob rau hauv zus tau tej cov tshiab, high-zoo plastics.

Ib qho txiaj ntsig tseem ceeb ntawm kev rov ua dua tshuaj lom neeg yog tias nws yog txheej txheem kho dua tshiab uas cov yas zoo tsis degrade ib zaug ua tiav tsis zoo li feem ntau ntawm cov khoom siv rov ua dua tshiab.Cov yas uas tau tshwm sim tuaj yeem siv los ua ntau yam khoom xws li cov thawv ntim khoom noj thiab cov khoom siv rau kev kho mob thiab kev noj qab haus huv uas yuav tsum muaj kev ruaj ntseg ntawm cov khoom.