Sisebenza kanjani isiguquli sezimoto esisebenza ngezimoto?

Ngesikhathi sokusebenza kwenjini yomlilo yangaphakathi, kukhishwa amagesi e-exhaust emkhathini, okungezona kuphela izimbangela ezinkulu zokungcola komoya, kodwa futhi engenye yezimbangela zezifo eziningi.

Lawa magesi, aphuma ezinhlelweni zokukhipha izimoto, aqukethe izinto eziyingozi kakhulu, yingakho izimoto zesimanje zifakwe uhlelo olukhethekile lokukhipha, lapho i-catalyst ihlala ikhona.

Isiguquli se-catalytic sibhubhisa ama-molecule ayingozi kumagesi e-exhaust futhi siwenze aphephe ngangokunokwenzeka kubantu nasemvelweni.

Yini i-catalyst?

Isiguquli sokuguqula uhlobo lwedivayisi umsebenzi wayo omkhulu ukunciphisa ukukhishwa okuyingozi kusuka kumagesi okukhipha avela ezinjini zezimoto. Isakhiwo se-catalyst silula. Lesi yisiqukathi sensimbi esifakwe ohlelweni lokukhipha imoto.

Kunamapayipi amabili ethangini. "Okokufaka" kwesiguquli kuxhunywe enjinini, futhi amagesi okukhipha angena ngayo, futhi "okukhiphayo" kuxhunywe kusonator yesistimu yokukhipha imoto.

Lapho amagesi e-exhaust avela enjinini engena ku-catalyst, kwenzeka kuwo amakhemikhali. Bacekela phansi amagesi ayingozi futhi bawaphendule abe amagesi angenabungozi angakhishelwa emvelweni.

Yiziphi izinto zesiguquli se-catalytic?

Ukwenza kucace kancane ukuthi isiguquli sezimoto esisebenza kanjani, ake sibheke ukuthi ziyini izakhi zaso eziyinhloko. Ngaphandle kokungena emininingwaneni, sizobhala kuphela izinto eziyinhloko lapho zakhiwe khona.

Isigatshana

I-substrate yisakhiwo sangaphakathi se-catalyst lapho i-catalyst nezinsimbi eziyigugu zimbozwe khona. Kunezinhlobo eziningana zama-substrates. Umehluko wabo omkhulu yizinto ezenziwe ngazo. Imvamisa kuba into engasebenzi eqinisa izinhlayiya ezisebenzayo ebusweni bayo.

Ukupheka

I-catalyst material esebenzayo ngokuvamile iqukethe i-alumina kanye nezinhlanganisela ezifana ne-cerium, i-zirconium, i-nickel, i-barium, i-lanthanum nabanye. Inhloso yokumboza iwukwandisa indawo ebonakalayo ye-substrate futhi isebenze njengesisekelo lapho izinsimbi eziyigugu zifakwa khona.

Izinsimbi eziyigugu

Izinsimbi eziyigugu ezikhona kusiguquli se-catalytic zisebenza ukwenza ukusabela okubaluleke kakhulu kwe-catalytic. Izinsimbi eziyigugu ezivame ukusetshenziswa yi-platinum, i-palladium ne-rhodium, kodwa eminyakeni yamuva nje inani elikhulu labakhiqizi seliqalile ukusebenzisa igolide.

Izindlu

Indlu igobolondo langaphandle ledivayisi futhi iqukethe i-substrate nezinye izakhi ze-catalyst. Izinto okwenziwa ngazo ikesi ngokuvamile ziyinsimbi engagqwali.

Amapayipi

Amapayipi axhumanisa isiguquli semoto esisebenzisayo nohlelo lwenjini nemoto. Zenziwe ngensimbi engagqwali.

Sisebenza kanjani isiguquli sezimoto esisebenza ngezimoto?

Ukusebenza kwenjini yomlilo yangaphakathi, kubalulekile ukuthi inqubo eqinile yomlilo yenhlanganisela yomoya-uphethiloli yenzeka kumasilinda ayo. Phakathi nale nqubo, kwakheka amagesi ayingozi njenge-carbon monoxide, i-nitrogen oxides, ama-hydrocarbon namanye.

Uma imoto ingenaso isiguquli sokukhanda, wonke la magesi ayingozi kakhulu, uma esekhishelwe ezinqeni eziningi ze-exhaust avela enjinini, azodlula ohlelweni lokukhipha bese engena emoyeni esiwuphefumulayo ngqo.

Uma imoto inesiguquli esisebenzisayo, amagesi e-exhaust azogobhoza esuka enjinini aye ku-muffler ngokusebenzisa ikhekheba lezinyosi le-substrate futhi asabele ngezinsimbi eziyigugu. Ngenxa yokusabela kwamakhemikhali, izinto ezinobungozi ziyancishiswa, futhi kuphela ukukhipha okungenabungozi, ikakhulukazi isikhutha, okungena emvelweni kusuka ohlelweni lokukhipha.

Siyazi ngezifundo zamakhemikhali ukuthi i-catalyst yinto ebangela noma esheshisa ukusabela kwamakhemikhali ngaphandle kokuyithinta. Ama-Catalyst abamba iqhaza ekuphenduleni kodwa awawona ama-reactants noma imikhiqizo ye-catalytic reaction.

Kunezigaba ezimbili lapho amagesi anobungozi kudlula khona i-catalyst: ukunciphisa kanye ne-oxidation. Isebenza kanjani?

Lapho ukushisa kokusebenza kwe-catalyst kufinyelela kuma-500 kuye ku-1200 degrees Fahrenheit noma ama-250-300 degrees Celsius, kwenzeka izinto ezimbili: ukunciphisa, futhi ngokushesha ngemuva kwalokho ukusabela kwe-oxidation. Lokhu kuzwakala kuyinkimbinkimbi kancane, kepha empeleni kusho ukuthi ama-molecule ento kanyekanye alahlekelwa futhi athole ama-electron, aguqula ukwakheka kwawo.

Ukwehliswa (ukumuncwa komoya-mpilo) okwenzeka ku-catalyst kuhlose ukuguqula i-nitric oxide ibe yigesi elungele imvelo.

Ngabe i-catalyst yezimoto isebenza kanjani esigabeni sokutakula?

Lapho i-nitrous oxide evela kumagesi aqeda imoto ingena ku-catalyst, i-platinum ne-rhodium ekuyo iqala ukusebenza ngokubola kwama-molecule e-nitrogen oxide, kuguqula igesi eyingozi ibe yinto engenabungozi ngokuphelele.

Kwenzekani ngesikhathi sesigaba se-oxidation?

Isinyathelo sesibili esivela ku-catalyst sibizwa ngokuthi i-oxidation reaction, lapho ama-hydrocarbon angashiswanga aguqulwa abe yi-carbon dioxide namanzi ngokuhlangana ne-oxygen (oxidation).

Ukusabela okwenzeka ku-catalyst kuguqula ukwakheka kwamakhemikhali kwamagesi e-exhaust, kuguqula ukwakheka kwe-athomu elenziwe ngalo. Lapho ama-molecule amagesi ayingozi edlula esuka enjinini aya ku-catalyst, awaphula abe ama-athomu. Ama-athomu wona, aphinde ahlangane abe ama-molecule ukuze akhe izinto ezingenabungozi njenge-carbon dioxide, i-nitrogen namanzi, bese ededelwa emvelweni ngohlelo lwe-exhaust.

Izinhlobo eziyinhloko zabaguquleli abakhanda izinjini ezisetshenziswa ezinjini zikaphethiloli zimbili: izindlela ezimbili nezindlela ezintathu.

Bilateral

I-catalyst enezindonga ezimbili (emaceleni amabili) ngasikhathi sinye yenza imisebenzi emibili: i-oxidize i-carbon monoxide ku-carbon dioxide futhi ihlanganise ama-hydrocarbon (uphethiloli ongashiswanga noma oshiswe kancane) ku-carbon dioxide namanzi.

Lolu hlobo lwesikhangisi sezimoto lwasetshenziswa ezinjinini zikadizili nophethiloli ukunciphisa ukukhishwa okuyingozi kwama-hydrocarbon ne-carbon monoxide kwaze kwaba ngo-1981, kodwa njengoba ingakwazanga ukuguqula i-nitrogen oxides, ngemuva kwama-81 yathathelwa indawo yizihlanganisi zezindlela ezintathu.

Izindlela ezintathu zokuguqula kabusha okuguqula kabusha

Lolu hlobo lwesikhangisi sezimoto, njengoba kwavela, lwethulwa ngo-1981, futhi namuhla selufakwe kuzo zonke izimoto zesimanje. I-catalyst yezindlela ezintathu yenza imisebenzi emithathu ngasikhathi sinye:

• kunciphisa i-nitric oxide ibe yi-nitrogen ne-oxygen;
• ihlanganisa i-carbon monoxide ku-carbon dioxide;
• ihlanganisa ama-hydrocarbon angashiswanga ku-carbon dioxide namanzi.

Ngenxa yokuthi lolu hlobo lwesiguquli se-catalytic lwenza kokubili izinyathelo zokunciphisa kanye ne-oxidation ye-catalysis, lenza umsebenzi walo ngokusebenza kahle okungafika ku-98%. Lokhu kusho ukuthi uma imoto yakho ifakwe isiguquli se-catalytic esinjalo, ngeke ingcolise imvelo ngezinto ezikhishwayo eziyingozi.

Izinhlobo zezinto zokudonsa izinjini zikadizili

Ezimotweni zikadizili, kuze kube muva nje, esinye sezinguquko ezijwayeleke kakhulu ezisetshenziswayo kwakuyi-Diesel Oxidation Catalyst (DOC). Lesi sikhombisi sisebenzisa i-oksijini emfudlaneni we-exhaust ukuguqula isikhutha sibe yi-carbon dioxide nama-hydrocarbon abe ngamanzi ne-carbon dioxide. Ngeshwa, lolu hlobo lwe-catalyst lusebenza kuphela ngama-90% futhi luyakwazi ukuqeda iphunga ledizili nokunciphisa izinhlayiya ezibonakalayo, kepha alusebenzi ekunciphiseni ukukhishwa kwe-NO x.

Izinjini zikadizili zikhipha amagesi aqukethe izinga eliphakeme kakhulu lezinto eziyizinhlayiyana (insizi), equkethe ikakhulu i-elemental carbon, okuyinto i-DOC catalysts engakwazi ukubhekana nayo, ngakho-ke izinhlayiya kufanele zisuswe kusetshenziswa lokho okubizwa ngokuthi yi-particulate filters (DPF).

Agcinwa kanjani ama-catalysts?

Ukugwema izinkinga nge-catalyst, kubalulekile ukwazi ukuthi:

• Impilo ye-catalyst ejwayelekile ingamakhilomitha ayi-160000. Ngemuva kokuhamba leli banga, udinga ukucabanga ukufaka esikhundleni se-transducer.
• Uma imoto ifakwe isiguquli se-catalytic, akufanele usebenzise uphethiloli oholayo, ngoba kunciphisa ukusebenza kwe-catalyst. Okuwukuphela kukaphethiloli ofanelekile kuleli cala awunalede.

Akungabazeki ukuthi izinzuzo zalawa madivayisi emvelo nasempilweni yethu zikhulu kakhulu, kepha ngaphezu kwezinzuzo zawo, nawo anezinkinga zawo.

Enye yezinkinga zabo ezinkulu ukuthi basebenza kuphela emazingeni okushisa aphezulu. Ngamanye amagama, uma uqala imoto yakho, isiguquli se-catalytic senza cishe lutho ukunciphisa ukukhipha ugesi.

Iqala ukusebenza kahle ngemuva kokuthi amagesi e-exhaust ashubile afinyelela kuma-250-300 degrees Celsius. Yingakho abanye abakhiqizi bezimoto bethathe izinyathelo zokubhekana nale nkinga ngokususa i-catalyst eduze nenjini, okuthi ngakolunye uhlangothi ithuthukise ukusebenza kocingo kodwa inciphise isikhathi sayo sokuphila ngoba ukusondela kwayo enjinini kuyiveza emazingeni okushisa aphezulu kakhulu.

Eminyakeni yamuva nje, kunqunywe ukuthi kufakwe isiguquli sokulawula ngaphansi kwesihlalo sabagibeli ebangeni elizosivumela ukuthi sisebenze kahle ngaphandle kokuvezwa amazinga okushisa aphezulu enjini.

Okunye okungalungile kwama-catalyst ukuvinjelwa njalo nokushiswa kwamakhekhe. Ngokuvamile ukutubeka kwenzeka ngenxa yophethiloli ongashisiwe ongena ohlelweni lwe-exhaust olubaswa kokuphakelayo kwesiguquli se-catalytic. Ukuvaleka ngokuvamile kwenzeka ngenxa kaphethiloli ompofu noma ongafanelekile, ukuguga okuvamile, isitayela sokushayela, njll.

Lokhu kungukuntula okuncane kakhulu uma kuqhathaniswa nokwakheka ngemuva kwezinzuzo ezinkulu esizithola ngokusebenzisa izixazululi zezimoto. Ngenxa yale mishini, ukukhishwa okuyingozi okuvela ezimotweni kukhawuliwe.

Abanye abagxeki baphikisa ngokuthi i-carbon dioxide nayo iwukukhipha okuyingozi. Bakholelwa ukuthi i-catalyst ayidingeki emotweni, ngoba ukukhishwa okunjalo kwandisa umphumela wokushisa. Eqinisweni, uma imoto ingenayo i-catalytic converter futhi ikhiphela i-carbon monoxide emoyeni, le oxide ngokwayo izoshintsha ibe yi-carbon dioxide emkhathini.

Ngubani Owasungula I-Catalyst?

Yize ama-catalysts engazange avele ngobuningi kuze kube sekupheleni kweminyaka yama-1970, umlando wabo waqala ngaphambi kwesikhathi.

Ubaba we-catalyst uthathwa njengonjiniyela wamakhemikhali waseFrance u-Eugene Goudry, owathi ngo-1954 wagunyaza ukusungulwa kwakhe ngaphansi kwegama elithi "Exhaust Catalytic Converter".

Ngaphambi kwalokhu kusungulwa, uGoodry wasungula ukuqhekeka okwandayo, lapho amakhemikhali amakhulu ayinkimbinkimbi ahlukaniswa abe yimikhiqizo engenabungozi. Wabe esezama izinhlobo ezahlukene zikaphethiloli, inhloso yakhe kwakuwukwenza kuhlanzeke.

Ukusetshenziswa kwangempela kwezikhangisi ezimotweni kwenzeka maphakathi nawo-1970, lapho kwethulwa imithetho eqinile yokulawula ukungcola edinga ukususwa komthofu ekuqothulweni kuphethiloli osezingeni eliphansi.

Imibuzo nezimpendulo:

Ungahlola kanjani ukuba khona kwe-catalyst emotweni? Ukuze wenze lokhu, vele ubheke ngaphansi kwemoto. Ngaphezu kwe-muffler eyinhloko kanye ne-muffler encane (i-resonator emi ngaphambili kwe-exhaust system), i-catalyst ingenye i-bulb.

Sikuphi isiguquli se-catalytic emotweni? Njengoba i-catalyst kufanele isebenze ezimweni zokushisa eziphakeme, itholakala eduze ngangokunokwenzeka ne-multifold exhaust. Iphambi kwe-resonator.

Iyini i-catalyst emotweni? Lesi isiguquli se-catalytic - isibani esengeziwe ohlelweni lokukhipha umoya. Igcwele izinto ze-ceramic, izinyosi zazo eziboshwe ngensimbi eyigugu.