{"id":1794,"date":"2025-07-14T03:48:26","date_gmt":"2025-07-14T03:48:26","guid":{"rendered":"https:\/\/3waycatalyst.com\/?p=1794"},"modified":"2025-07-15T13:04:17","modified_gmt":"2025-07-15T13:04:17","slug":"the-essential-guide-to-three-way-catalytic-converters","status":"publish","type":"post","link":"https:\/\/3waycatalyst.com\/cs\/the-essential-guide-to-three-way-catalytic-converters\/","title":{"rendered":"Z\u00e1kladn\u00ed pr\u016fvodce t\u0159\u00edcestn\u00fdmi katalyz\u00e1tory"},"content":{"rendered":"

Zaveden\u00ed<\/strong><\/h2>\n\n\n\n

Ka\u017ed\u00e9 modern\u00ed vozidlo s benz\u00ednov\u00fdm motorem obsahuje ve sv\u00e9m v\u00fdfukov\u00e9m syst\u00e9mu pozoruhodn\u00fd prvek chemick\u00e9ho in\u017een\u00fdrstv\u00ed. Toto za\u0159\u00edzen\u00ed, t\u0159\u00edcestn\u00fd katalyz\u00e1tor<\/strong>, slou\u017e\u00ed jedin\u00e9mu kl\u00ed\u010dov\u00e9mu \u00fa\u010delu: neutralizovat nej\u0161kodliv\u011bj\u0161\u00ed zne\u010di\u0161\u0165uj\u00edc\u00ed l\u00e1tky produkovan\u00e9 spalovac\u00edm motorem. Bez n\u011bj by se na\u0161e m\u011bsta dusila smogem a kvalita ovzdu\u0161\u00ed by p\u0159edstavovala v\u00fdznamnou hrozbu pro ve\u0159ejn\u00e9 zdrav\u00ed. Spalovac\u00ed proces motoru je sice v\u00fdkonn\u00fd, ale nedokonal\u00fd. Vytv\u00e1\u0159\u00ed toxick\u00e9 vedlej\u0161\u00ed produkty, jako je oxid uhelnat\u00fd, nesp\u00e1len\u00e9 uhlovod\u00edky a oxidy dus\u00edku. Trojcestn\u00fd katalyz\u00e1tor funguje jako posledn\u00ed obrann\u00e1 linie. Transformuje tyto nebezpe\u010dn\u00e9 plyny na ne\u0161kodn\u00e9 l\u00e1tky je\u0161t\u011b p\u0159edt\u00edm, ne\u017e se dostanou do v\u00fdfuku. Tento \u010dl\u00e1nek poskytuje v\u011bdeck\u00fd a technick\u00fd pr\u016fzkum t\u0159\u00edcestn\u00e9ho katalyz\u00e1toru. Prozkoum\u00e1me jeho historii, slo\u017eit\u00e9 chemick\u00e9 procesy, fyzik\u00e1ln\u00ed slo\u017eky a p\u0159esn\u00e9 podm\u00ednky pot\u0159ebn\u00e9 pro jeho efektivn\u00ed fungov\u00e1n\u00ed.<\/p>\n\n\n\n

Kapitola 1: V\u00fdvoj od dvoucestn\u00fdch k t\u0159\u00edcestn\u00fdm p\u0159evodn\u00edk\u016fm<\/strong><\/h2>\n\n\n\n

Cesta k modern\u00edmu t\u0159\u00edcestn\u00fd katalyz\u00e1tor<\/strong> za\u010dalo s rostouc\u00edm pov\u011bdom\u00edm o zne\u010di\u0161t\u011bn\u00ed ovzdu\u0161\u00ed. V polovin\u011b 20. stolet\u00ed v\u011bdci a regula\u010dn\u00ed org\u00e1ny identifikovali v\u00fdfukov\u00e9 plyny vozidel jako prim\u00e1rn\u00ed zdroj m\u011bstsk\u00e9ho smogu. Prvn\u00ed v\u00fdznamnou legislativn\u00ed reakc\u00ed ve Spojen\u00fdch st\u00e1tech byl z\u00e1kon o \u010dist\u00e9m ovzdu\u0161\u00ed, kter\u00fd zmocnil Agenturu pro ochranu \u017eivotn\u00edho prost\u0159ed\u00ed (EPA) ke stanoven\u00ed p\u0159\u00edsn\u00fdch limit\u016f pro emise vozidel.<\/p>\n\n\n\n

Prvn\u00ed krok: Dvoucestn\u00e9 oxida\u010dn\u00ed konvertory<\/strong><\/h3>\n\n\n\n

Automobilky zpo\u010d\u00e1tku reagovaly \u201edvoucestn\u00fdm\u201c katalyz\u00e1torem. Tato za\u0159\u00edzen\u00ed se poprv\u00e9 objevila ve velk\u00e9m m\u011b\u0159\u00edtku na americk\u00e9m trhu ve v\u011bt\u0161in\u011b vozidel modelov\u00e9ho roku 1975. Jejich \u00fakolem bylo \u0159e\u0161it dva ze t\u0159\u00ed hlavn\u00edch zne\u010di\u0161\u0165uj\u00edc\u00edch l\u00e1tek: oxid uhelnat\u00fd (CO) a nesp\u00e1len\u00e9 uhlovod\u00edky (HC).<\/p>\n\n\n\n

Tyto ran\u00e9 konvertory fungovaly jako oxida\u010dn\u00ed katalyz\u00e1tory. Uvnit\u0159 za\u0159\u00edzen\u00ed reagoval kysl\u00edk z v\u00fdfukov\u00e9ho proudu s CO a HC. Tato chemick\u00e1 reakce, urychlen\u00e1 katalyz\u00e1tory, jako je platina a palladium, je p\u0159em\u011bnila na dv\u011b mnohem bezpe\u010dn\u011bj\u0161\u00ed slou\u010deniny: oxid uhli\u010dit\u00fd (CO\u2082) a vodu (H\u2082O). A\u010dkoli byly v tomto konkr\u00e9tn\u00edm \u00fakolu \u00fa\u010dinn\u00e9, dvoucestn\u00e9 konvertory nijak ne\u0159e\u0161ily t\u0159et\u00ed hlavn\u00ed zne\u010di\u0161\u0165uj\u00edc\u00ed l\u00e1tku: oxidy dus\u00edku (NOx). NOx je kl\u00ed\u010dovou slo\u017ekou p\u0159i tvorb\u011b kysel\u00fdch de\u0161\u0165\u016f a p\u0159\u00edzemn\u00edho ozonu.<\/p>\n\n\n\n

Komplexn\u00ed \u0159e\u0161en\u00ed: P\u0159\u00edchod t\u0159\u00edcestn\u00e9ho p\u0159evodn\u00edku<\/strong><\/h3>\n\n\n\n

S p\u0159\u00edsn\u011bj\u0161\u00edmi p\u0159edpisy se nal\u00e9hav\u011b zv\u00fd\u0161ila pot\u0159eba komplexn\u011bj\u0161\u00edho \u0159e\u0161en\u00ed. In\u017een\u00fd\u0159i vyvinuli \u201et\u0159\u00edcestn\u00fd\u201c m\u011bni\u010d, kter\u00fd by \u0159e\u0161il v\u0161echny t\u0159i t\u0159\u00eddy zne\u010di\u0161\u0165uj\u00edc\u00edch l\u00e1tek sou\u010dasn\u011b. Spole\u010dnost Volvo byla pr\u016fkopn\u00edkem a v roce 1977 p\u0159edstavila prvn\u00ed komer\u010dn\u00ed t\u0159\u00edcestn\u00e9 m\u011bni\u010de ve sv\u00fdch vozidlech pro kalifornsk\u00fd trh, kter\u00fd m\u011bl nejp\u0159\u00edsn\u011bj\u0161\u00ed emisn\u00ed z\u00e1kony.<\/p>\n\n\n\n

Do modelov\u00e9ho roku 1981 feder\u00e1ln\u00ed p\u0159edpisy po\u017eadovaly v\u00fdrazn\u00e9 sn\u00ed\u017een\u00ed emis\u00ed NOx. Tento p\u0159\u00edkaz fakticky zp\u016fsobil, \u017ee t\u0159\u00edcestn\u00fd katalyz\u00e1tor<\/strong> standardn\u00ed a nezbytn\u00e1 sou\u010d\u00e1st v\u0161ech nov\u00fdch automobil\u016f s benz\u00ednov\u00fdm motorem ve Spojen\u00fdch st\u00e1tech. Tato technologie p\u0159edstavovala velk\u00fd skok vp\u0159ed, proto\u017ee krom\u011b oxidace zahrnovala i druh\u00fd chemick\u00fd proces \u2013 redukci. Tato dvoj\u00ed schopnost z n\u00ed d\u011bl\u00e1 \u201et\u0159\u00edcestnou\u201c.<\/p>\n\n\n\n

Srovn\u00e1n\u00ed: Dvoucestn\u00e9 vs. t\u0159\u00edcestn\u00e9 katalyz\u00e1tory<\/strong><\/h3>\n\n\n\n

Rozd\u00edl mezi t\u011bmito dv\u011bma technologiemi je z\u00e1sadn\u00ed. N\u00ed\u017ee uveden\u00e1 tabulka shrnuje jejich kl\u00ed\u010dov\u00e9 rozd\u00edly. Modern\u00ed vozidla pou\u017e\u00edvaj\u00ed v\u00fdhradn\u011b t\u0159\u00edcestn\u00e9 m\u011bni\u010de, aby spl\u0148ovala komplexn\u00ed glob\u00e1ln\u00ed emisn\u00ed normy.<\/p>\n\n\n\n

Funkce<\/th>Dvoucestn\u00fd katalyz\u00e1tor<\/th>Trojcestn\u00fd katalyz\u00e1tor<\/th><\/tr><\/thead>
O\u0161et\u0159en\u00e9 zne\u010di\u0161\u0165uj\u00edc\u00ed l\u00e1tky<\/strong><\/td>Oxid uhelnat\u00fd (CO), uhlovod\u00edky (HC)<\/td>Oxid uhelnat\u00fd (CO), uhlovod\u00edky (HC), oxidy dus\u00edku (NOx)<\/td><\/tr>
Prim\u00e1rn\u00ed chemick\u00fd proces<\/strong><\/td>Oxidace<\/td>Oxidace a redukce<\/td><\/tr>
Pou\u017eit\u00e9 katalytick\u00e9 kovy<\/strong><\/td>Platina (Pt), Palladium (Pd)<\/td>Platina (Pt), Palladium (Pd), Rhodium (Rh)<\/strong><\/td><\/tr>
Prim\u00e1rn\u00ed funkce<\/strong><\/td>P\u0159em\u011b\u0148uje CO na CO\u2082 a HC na CO\u2082 + H\u2082O<\/td>Prov\u00e1d\u00ed stejn\u00e9 oxida\u010dn\u00ed reakce plus<\/strong> redukuje NOx na N\u2082<\/td><\/tr>
Modern\u00ed aplikace<\/strong><\/td>Zastaral\u00e9 u benz\u00ednov\u00fdch automobil\u016f; pou\u017e\u00edv\u00e1 se u n\u011bkter\u00fdch naftov\u00fdch a chud\u00e9 sm\u011bsi<\/td>Standardn\u00ed v\u00fdbava prakticky v\u0161ech modern\u00edch vozidel s benz\u00ednov\u00fdm motorem<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Kapitola 2: Z\u00e1kladn\u00ed chemie t\u0159\u00edcestn\u00e9ho katalyz\u00e1toru<\/strong><\/h2>\n\n\n\n

A t\u0159\u00edcestn\u00fd katalyz\u00e1tor<\/strong> je v podstat\u011b chemick\u00fd reaktor. Vyu\u017e\u00edv\u00e1 specifick\u00e9 materi\u00e1ly, zn\u00e1m\u00e9 jako katalyz\u00e1tory, k urychlen\u00ed chemick\u00fdch reakc\u00ed, ani\u017e by se p\u0159i tom spot\u0159ebov\u00e1valy. N\u00e1zev \u201et\u0159\u00edcestn\u00fd\u201c ozna\u010duje jeho schopnost podporovat t\u0159i sou\u010dasn\u00e9 chemick\u00e9 transformace. Tyto reakce jsou seskupeny do dvou odli\u0161n\u00fdch proces\u016f: redukce a oxidace.<\/p>\n\n\n\n

Tyto dva procesy prob\u00edhaj\u00ed v odd\u011blen\u00fdch f\u00e1z\u00edch nebo na r\u016fzn\u00fdch katalyz\u00e1torov\u00fdch materi\u00e1lech uvnit\u0159 sk\u0159\u00edn\u011b katalyz\u00e1toru. Aby oba fungovaly efektivn\u011b, mus\u00ed \u0159\u00eddic\u00ed jednotka motoru udr\u017eovat velmi p\u0159esnou rovnov\u00e1hu paliva a vzduchu.<\/p>\n\n\n\n

Reduk\u010dn\u00ed reakce: Neutralizace oxid\u016f dus\u00edku (NOx)<\/strong><\/h3>\n\n\n\n

Prvn\u00ed f\u00e1ze p\u0159em\u011bny se zam\u011b\u0159uje na nejobt\u00ed\u017en\u011bj\u0161\u00ed zne\u010di\u0161\u0165uj\u00edc\u00ed l\u00e1tky, oxidy dus\u00edku (NOx). Tato skupina plyn\u016f vznik\u00e1 reakc\u00ed dus\u00edku a kysl\u00edku za podm\u00ednek vysok\u00e9ho tlaku a vysok\u00e9 teploty uvnit\u0159 v\u00e1lc\u016f motoru.<\/p>\n\n\n\n

Reduk\u010dn\u00ed katalyz\u00e1tor je zodpov\u011bdn\u00fd za rozklad NOx. Rhodium (Rh) je pro tento \u00fakol preferovan\u00fdm drah\u00fdm kovem. M\u00e1 jedine\u010dnou schopnost odd\u011blovat atomy kysl\u00edku od molekul oxidu dus\u00edku. Tato reakce uvol\u0148uje atomy dus\u00edku, kter\u00e9 se pak vz\u00e1jemn\u011b v\u00e1\u017eou a vytv\u00e1\u0159ej\u00ed ne\u0161kodn\u00fd plynn\u00fd dus\u00edk (N\u2082), prim\u00e1rn\u00ed slo\u017eku vzduchu, kter\u00fd d\u00fdch\u00e1me.<\/p>\n\n\n\n

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  • Chemick\u00e1 reakce:<\/strong> 2NOx \u2192 xO\u2082 + N\u2082<\/li>\n<\/ul>\n\n\n\n

    V t\u00e9to reakci rhodiov\u00fd katalyz\u00e1tor usnad\u0148uje rozklad NOx na element\u00e1rn\u00ed kysl\u00edk a stabiln\u00ed plynn\u00fd dus\u00edk.<\/p>\n\n\n\n

    Oxida\u010dn\u00ed reakce: \u010ci\u0161t\u011bn\u00ed CO a HC<\/strong><\/h3>\n\n\n\n

    Druh\u00fd stupe\u0148 zpracov\u00e1v\u00e1 oxid uhelnat\u00fd (CO) a nesp\u00e1len\u00e9 uhlovod\u00edky (HC). Oxid uhelnat\u00fd je jedovat\u00fd plyn vznikaj\u00edc\u00ed nedokonal\u00fdm spalov\u00e1n\u00edm paliva. Uhlovod\u00edky jsou jednodu\u0161e surov\u00e9, nesp\u00e1len\u00e9 \u010d\u00e1stice paliva.<\/p>\n\n\n\n

    Oxida\u010dn\u00ed katalyz\u00e1tor vyu\u017e\u00edv\u00e1 kysl\u00edk uvoln\u011bn\u00fd b\u011bhem reduk\u010dn\u00ed f\u00e1ze spolu s ve\u0161ker\u00fdm dal\u0161\u00edm dostupn\u00fdm kysl\u00edkem ve v\u00fdfukov\u00fdch plynech k p\u0159em\u011bn\u011b t\u011bchto dvou zne\u010di\u0161\u0165uj\u00edc\u00edch l\u00e1tek. Platina (Pt) a palladium (Pd) jsou prim\u00e1rn\u00ed kovy pou\u017e\u00edvan\u00e9 v tomto procesu. Podporuj\u00ed reakce, kter\u00e9 p\u0159id\u00e1vaj\u00ed kysl\u00edk k molekul\u00e1m CO a HC.<\/p>\n\n\n\n

      \n
    • Oxidace oxidu uhelnat\u00e9ho:<\/strong> 2CO + O\u2082 \u2192 2CO\u2082<\/li>\n\n\n\n
    • Oxidace uhlovod\u00edk\u016f:<\/strong> C\u2093H\u2082\u2093\u208a\u2082 + [(3x+1)\/2]O\u2082 \u2192 xCO\u2082 + (x+1)H\u2082O<\/li>\n<\/ul>\n\n\n\n

      Tento proces p\u0159em\u011b\u0148uje toxick\u00fd oxid uhelnat\u00fd na netoxick\u00fd oxid uhli\u010dit\u00fd (CO\u2082) a zne\u010di\u0161\u0165uj\u00edc\u00ed uhlovod\u00edky na oxid uhli\u010dit\u00fd a vodn\u00ed p\u00e1ru (H\u2082O).<\/p>\n\n\n\n

      Shrnut\u00ed chemick\u00fdch transformac\u00ed<\/strong><\/h3>\n\n\n\n

      N\u00ed\u017ee uveden\u00e1 tabulka shrnuje vstupn\u00ed zne\u010di\u0161\u0165uj\u00edc\u00ed l\u00e1tky a jejich v\u00fdstupn\u00ed produkty po pr\u016fchodu t\u0159\u00edcestn\u00fd katalyz\u00e1tor<\/strong>.<\/p>\n\n\n\n

      Vstupn\u00ed zne\u010di\u0161\u0165uj\u00edc\u00ed l\u00e1tka<\/th>Chemick\u00fd vzorec<\/th>Typ reakce<\/th>Katalyz\u00e1torov\u00fd kov<\/th>V\u00fdstupn\u00ed produkt<\/th>Chemick\u00fd vzorec<\/th><\/tr><\/thead>
      Oxidy dus\u00edku<\/td>NOx<\/td>Sn\u00ed\u017een\u00ed<\/td>Rhodium (Rh)<\/td>Dus\u00edk<\/td>N\u2082<\/td><\/tr>
      Oxid uhelnat\u00fd<\/td>CO<\/td>Oxidace<\/td>Platina (Pt), Palladium (Pd)<\/td>Oxid uhli\u010dit\u00fd<\/td>CO\u2082<\/td><\/tr>
      Uhlovod\u00edky<\/td>Hlavn\u00ed m\u011bsto<\/td>Oxidace<\/td>Platina (Pt), Palladium (Pd)<\/td>Oxid uhli\u010dit\u00fd a voda<\/td>CO\u2082 a H\u2082O<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

      Kapitola 3: Anatomie t\u0159\u00edcestn\u00e9ho katalyz\u00e1toru<\/strong><\/h2>\n\n\n\n

      I kdy\u017e je chemie slo\u017eit\u00e1, fyzik\u00e1ln\u00ed struktura konvertoru je navr\u017eena pro maxim\u00e1ln\u00ed \u00fa\u010dinnost a trvanlivost. Skl\u00e1d\u00e1 se ze t\u0159\u00ed hlavn\u00edch komponent, kter\u00e9 pracuj\u00ed spole\u010dn\u011b: substr\u00e1tu, kryc\u00ed vrstvy a katalytick\u00e9 vrstvy.<\/p>\n\n\n\n

      Substr\u00e1t: Z\u00e1klad s maxim\u00e1ln\u00ed povrchovou plochou<\/strong><\/h3>\n\n\n\n

      J\u00e1drem p\u0159evodn\u00edku je substr\u00e1t. Jedn\u00e1 se o keramick\u00fd monolit, obvykle vyroben\u00fd z kordieritu, nebo n\u011bkdy z kovov\u00e9 struktury. Nejedn\u00e1 se o pevn\u00fd blok, ale o slo\u017eitou vo\u0161tinovou strukturu. Tato konstrukce obsahuje tis\u00edce drobn\u00fdch paraleln\u00edch kan\u00e1lk\u016f.<\/p>\n\n\n\n

      \u00da\u010delem vo\u0161tiny je maximalizovat povrchovou plochu, kter\u00e1 p\u0159ich\u00e1z\u00ed do styku s v\u00fdfukov\u00fdmi plyny. V\u011bt\u0161\u00ed povrchov\u00e1 plocha umo\u017e\u0148uje efektivn\u011bj\u0161\u00ed a rychlej\u0161\u00ed chemick\u00e9 reakce v kompaktn\u00edm fyzick\u00e9m prostoru. Hustota t\u011bchto kan\u00e1l\u016f, m\u011b\u0159en\u00e1 v bu\u0148k\u00e1ch na \u010dtvere\u010dn\u00ed palec (CPSI), se m\u016f\u017ee li\u0161it. Vysoce v\u00fdkonn\u00e9 aplikace mohou pro lep\u0161\u00ed konverzi pou\u017e\u00edvat vy\u0161\u0161\u00ed CPSI, zat\u00edmco standardn\u00ed vozidla pou\u017e\u00edvaj\u00ed rovnov\u00e1hu mezi \u00fa\u010dinnost\u00ed a pr\u016ftokem.<\/p>\n\n\n\n

      Podkladov\u00fd materi\u00e1l mus\u00ed m\u00edt n\u011bkolik kl\u00ed\u010dov\u00fdch vlastnost\u00ed:<\/p>\n\n\n\n

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      • Odolnost v\u016f\u010di vysok\u00fdm teplot\u00e1m:<\/strong> Mus\u00ed odol\u00e1vat teplot\u00e1m v\u00fdfukov\u00fdch plyn\u016f p\u0159esahuj\u00edc\u00edm 1200 \u00b0C (2200 \u00b0F).<\/li>\n\n\n\n
      • Tepeln\u00e1 stabilita:<\/strong> Nem\u011bl by praskat ani se deformovat p\u0159i n\u00e1hl\u00fdch zm\u011bn\u00e1ch teploty.<\/li>\n\n\n\n
      • Konstruk\u010dn\u00ed pevnost:<\/strong> Mus\u00ed odol\u00e1vat neust\u00e1l\u00fdm vibrac\u00edm a tlak\u016fm v\u00fdfukov\u00e9ho syst\u00e9mu.<\/li>\n\n\n\n
      • N\u00edzk\u00e9 n\u00e1klady:<\/strong> V\u00fdrobci to mus\u00ed vyr\u00e1b\u011bt ekonomicky a ve velk\u00e9m m\u011b\u0159\u00edtku.<\/li>\n<\/ul>\n\n\n\n

        N\u00e1t\u011br: Zv\u011bt\u0161en\u00ed reaktivn\u00edho povrchu<\/strong><\/h3>\n\n\n\n

        Samotn\u00fd keramick\u00fd substr\u00e1t nen\u00ed katalyticky aktivn\u00ed. Pro jeho p\u0159\u00edpravu na drah\u00e9 kovy nan\u00e1\u0161ej\u00ed v\u00fdrobci \u201ewashcoat\u201c. Jedn\u00e1 se o vrstvu por\u00e9zn\u00edho materi\u00e1lu, nej\u010dast\u011bji oxidu hlinit\u00e9ho (Al\u2082O\u2083), nanesenou na cel\u00fd vnit\u0159n\u00ed povrch vo\u0161tinov\u00e9 struktury.<\/p>\n\n\n\n

        Funkc\u00ed omyvac\u00edho n\u00e1t\u011bru je dramaticky zv\u00fd\u0161it efektivn\u00ed povrchovou plochu na mikroskopick\u00e9 \u00farovni. Jeho drsn\u00e1, por\u00e9zn\u00ed textura vytv\u00e1\u0159\u00ed nespo\u010det z\u00e1kout\u00ed a \u0161t\u011brbin, kde se mohou \u010d\u00e1stice katalyz\u00e1toru ukotvit. T\u00edm se exponenci\u00e1ln\u011b zvy\u0161uje po\u010det dostupn\u00fdch reaktivn\u00edch m\u00edst, \u010d\u00edm\u017e se konvertor st\u00e1v\u00e1 mnohem \u00fa\u010dinn\u011bj\u0161\u00edm, ne\u017e kdyby se kovy nan\u00e1\u0161ely p\u0159\u00edmo na hladkou keramiku.<\/p>\n\n\n\n

        Drah\u00e9 kovy: Katalytick\u00e1 elektr\u00e1rna<\/strong><\/h3>\n\n\n\n

        Posledn\u00ed a nejd\u016fle\u017eit\u011bj\u0161\u00ed vrstva obsahuje samotn\u00e9 katalyz\u00e1tory. Jsou to drah\u00e9 kovy ze skupiny platiny: Platina (Pt), palladium (Pd) a rhodium (Rh)<\/strong>Velmi tenk\u00e1 vrstva t\u011bchto kov\u016f je nalepena na povrch n\u00e1t\u011bru.<\/p>\n\n\n\n

          \n
        • Platina (Pt)<\/strong> je vynikaj\u00edc\u00ed oxida\u010dn\u00ed katalyz\u00e1tor, vysoce \u00fa\u010dinn\u00fd p\u0159i p\u0159em\u011bn\u011b CO i HC.<\/li>\n\n\n\n
        • Palladium (Pd)<\/strong> slou\u017e\u00ed tak\u00e9 jako oxida\u010dn\u00ed katalyz\u00e1tor a \u010dasto se pou\u017e\u00edv\u00e1 jako levn\u011bj\u0161\u00ed alternativa nebo dopln\u011bk platiny.<\/li>\n\n\n\n
        • Rhodium (Rh)<\/strong> je specializovan\u00fd reduk\u010dn\u00ed katalyz\u00e1tor. Jeho jedin\u00fdm \u00fa\u010delem je rozkl\u00e1dat NOx.<\/li>\n<\/ul>\n\n\n\n

          Vysok\u00e1 cena t\u011bchto kov\u016f je hlavn\u00edm d\u016fvodem, pro\u010d t\u0159\u00edcestn\u00e9 katalyz\u00e1tory<\/strong> jsou cenn\u00e9 a \u010dast\u00fdm c\u00edlem kr\u00e1de\u017e\u00ed. Automobilky neust\u00e1le hledaj\u00ed nov\u00e9 zp\u016fsoby, jak sn\u00ed\u017eit pot\u0159ebn\u00e9 mno\u017estv\u00ed drah\u00fdch kov\u016f (proces zvan\u00fd \u201esecondary\u201c), ani\u017e by byla ob\u011btov\u00e1na \u00fa\u010dinnost p\u0159em\u011bny.<\/p>\n\n\n\n

          Kapitola 4: Kritick\u00e9 podm\u00ednky pro optim\u00e1ln\u00ed v\u00fdkon<\/strong><\/h3>\n\n\n\n

          A t\u0159\u00edcestn\u00fd katalyz\u00e1tor<\/strong> nepracuje s maxim\u00e1ln\u00ed \u00fa\u010dinnost\u00ed za v\u0161ech podm\u00ednek. Pro jeho funkci jsou naprosto z\u00e1sadn\u00ed dva faktory: pom\u011br vzduchu a paliva a provozn\u00ed teplota. Syst\u00e9m \u0159\u00edzen\u00ed motoru vozidla je pe\u010dliv\u011b navr\u017een tak, aby tyto dv\u011b prom\u011bnn\u00e9 \u0159\u00eddil.<\/p>\n\n\n\n

          Stechiometrick\u00fd pom\u011br vzduch-palivo: K\u0159ehk\u00e1 rovnov\u00e1ha<\/strong><\/h3>\n\n\n\n

          Aby katalyz\u00e1tor efektivn\u011b prov\u00e1d\u011bl reduk\u010dn\u00ed i oxida\u010dn\u00ed reakce, mus\u00ed motor pracovat se stechiometrick\u00fdm pom\u011brem vzduch-palivo nebo velmi bl\u00edzk\u00fdm tomuto pom\u011bru. U benz\u00ednu je tento pom\u011br p\u0159ibli\u017en\u011b 14,7 hmotnostn\u00edch d\u00edl\u016f vzduchu k 1 hmotnostn\u00edmu d\u00edlu paliva (14,7:1).<\/p>\n\n\n\n

            \n
          • Pokud je sm\u011bs p\u0159\u00edli\u0161 bohat\u00e1 (p\u0159\u00edli\u0161 mnoho paliva)<\/strong>, nebude k dispozici dostatek kysl\u00edku k \u00fapln\u00e9 oxidaci CO a HC.<\/li>\n\n\n\n
          • Pokud je sm\u011bs p\u0159\u00edli\u0161 chud\u00e1 (p\u0159\u00edli\u0161 mnoho vzduchu)<\/strong>, p\u0159ebyte\u010dn\u00fd kysl\u00edk bude br\u00e1nit redukci NOx, proto\u017ee rhodiov\u00fd katalyz\u00e1tor nebude schopen \u00fa\u010dinn\u011b odstra\u0148ovat kysl\u00edk z molekul NOx.<\/li>\n<\/ul>\n\n\n\n

            \u201eIde\u00e1ln\u00ed m\u00edsto\u201c pro t\u0159\u00edcestn\u00fd katalyz\u00e1tor<\/strong> je velmi \u00fazk\u00e9 okno kolem tohoto stechiometrick\u00e9ho bodu. Pro udr\u017een\u00ed t\u00e9to rovnov\u00e1hy pou\u017e\u00edvaj\u00ed vozidla syst\u00e9m s uzav\u0159enou smy\u010dkou zp\u011btn\u00e9 vazby. Lambda sondy (nebo O2 sondy) um\u00edst\u011bn\u00e9 ve v\u00fdfukov\u00fdch plynech p\u0159ed a za katalyz\u00e1torem neust\u00e1le m\u011b\u0159\u00ed obsah kysl\u00edku. Tato data jsou p\u0159iv\u00e1d\u011bna zp\u011bt do \u0159\u00eddic\u00ed jednotky motoru (ECU), kter\u00e1 v re\u00e1ln\u00e9m \u010dase upravuje vst\u0159ikov\u00e1n\u00ed paliva, aby pom\u011br vzduchu a paliva byl dokonale vyv\u00e1\u017een\u00fd.<\/p>\n\n\n\n

            Teplota p\u0159i zhasnut\u00ed sv\u011btla: Pot\u0159eba tepla<\/strong><\/h3>\n\n\n\n

            Katalyz\u00e1tory vy\u017eaduj\u00ed minim\u00e1ln\u00ed teplotu, aby se staly chemicky aktivn\u00edmi. Tato teplota je zn\u00e1m\u00e1 jako \u201eteplota zhasnut\u00ed\u201c, kter\u00e1 se obvykle pohybuje mezi 250 \u00b0C a 300 \u00b0C (482 \u00b0F a\u017e 572 \u00b0F). Pod touto teplotou katalyz\u00e1tor jen velmi m\u00e1lo \u010dist\u00ed v\u00fdfukov\u00e9 plyny.<\/p>\n\n\n\n

            Proto jsou emise vozidla nejvy\u0161\u0161\u00ed b\u011bhem \u201estuden\u00e9ho startu\u201c. P\u0159i prvn\u00edm nastartov\u00e1n\u00ed motoru jsou v\u00fdfuk a katalyz\u00e1tor studen\u00e9. M\u016f\u017ee trvat n\u011bkolik minut j\u00edzdy, ne\u017e katalyz\u00e1tor dos\u00e1hne sv\u00e9 provozn\u00ed teploty. B\u011bhem t\u00e9to zah\u0159\u00edvac\u00ed doby proch\u00e1zej\u00ed neupraven\u00e9 zne\u010di\u0161\u0165uj\u00edc\u00ed l\u00e1tky p\u0159\u00edmo z v\u00fdfuku.<\/p>\n\n\n\n

            Pro \u0159e\u0161en\u00ed tohoto probl\u00e9mu vyvinuli in\u017een\u00fd\u0159i n\u011bkolik strategi\u00ed:<\/p>\n\n\n\n

              \n
            • Bl\u00edzko v\u00e1zan\u00e9 katalyz\u00e1tory (CCC):<\/strong> To zahrnuje um\u00edst\u011bn\u00ed men\u0161\u00edho p\u0159edb\u011b\u017en\u00e9ho katalyz\u00e1toru mnohem bl\u00ed\u017ee k v\u00fdfukov\u00e9mu potrub\u00ed motoru. Bli\u017e\u0161\u00ed um\u00edst\u011bn\u00ed ke zdroji tepla umo\u017e\u0148uje dos\u00e1hnout teploty pro zhasnut\u00ed mnohem rychleji, \u010dasto za m\u00e9n\u011b ne\u017e 20 sekund.<\/li>\n\n\n\n
            • Elektricky oh\u0159\u00edvan\u00e9 katalyz\u00e1tory (EHC):<\/strong> N\u011bkter\u00e9 pokro\u010dil\u00e9 syst\u00e9my pou\u017e\u00edvaj\u00ed elektrick\u00fd topn\u00fd \u010dl\u00e1nek k p\u0159edeh\u0159\u00e1t\u00ed katalyz\u00e1toru p\u0159ed nastartov\u00e1n\u00edm motoru nebo bezprost\u0159edn\u011b po n\u011bm. To m\u016f\u017ee v\u00fdrazn\u011b sn\u00ed\u017eit emise uhlovod\u00edk\u016f p\u0159i studen\u00e9m startu.<\/li>\n<\/ul>\n\n\n\n

              Kapitola 5: \u0160ir\u0161\u00ed dopad a modern\u00ed aplikace<\/strong><\/h2>\n\n\n\n

              Ten\/Ta\/To t\u0159\u00edcestn\u00fd katalyz\u00e1tor<\/strong> Je to v\u00edc ne\u017e jen sou\u010d\u00e1stka v automobilu; je to z\u00e1kladn\u00ed technologie pro glob\u00e1ln\u00ed ochranu \u017eivotn\u00edho prost\u0159ed\u00ed. Jej\u00ed \u0161irok\u00e9 roz\u0161\u00ed\u0159en\u00ed p\u0159\u00edmo p\u0159isp\u011blo k masivn\u00edmu sn\u00ed\u017een\u00ed zne\u010di\u0161t\u011bn\u00ed ovzdu\u0161\u00ed ve m\u011bstech po cel\u00e9m sv\u011bt\u011b.<\/p>\n\n\n\n

              Krom\u011b standardn\u00edch osobn\u00edch automobil\u016f je tato technologie uzp\u016fsobena pro \u0161irokou \u0161k\u00e1lu aplikac\u00ed, kter\u00e9 vyu\u017e\u00edvaj\u00ed spalovac\u00ed motory. Pat\u0159\u00ed sem:<\/p>\n\n\n\n

                \n
              • N\u00e1kladn\u00ed automobily a autobusy<\/li>\n\n\n\n
              • Motocykly<\/li>\n\n\n\n
              • Vysokozdvi\u017en\u00e9 voz\u00edky a t\u011b\u017eebn\u00ed za\u0159\u00edzen\u00ed<\/li>\n\n\n\n
              • Elektrick\u00e9 gener\u00e1tory<\/li>\n\n\n\n
              • Lokomotivy a n\u00e1mo\u0159n\u00ed plavidla<\/li>\n\n\n\n
              • Dokonce i n\u011bkter\u00e1 pokro\u010dil\u00e1 kamna na d\u0159evo pro regulaci emis\u00ed pevn\u00fdch \u010d\u00e1stic a plyn\u016f<\/li>\n<\/ul>\n\n\n\n

                V ka\u017ed\u00e9m p\u0159\u00edpad\u011b jsou z\u00e1kladn\u00ed principy t\u0159\u00edcestn\u00e9 katal\u00fdzy p\u0159izp\u016fsobeny specifick\u00fdm p\u0159edpis\u016fm a provozn\u00edm podm\u00ednk\u00e1m. Neust\u00e1l\u00fd rozvoj t\u00e9to technologie je poh\u00e1n\u011bn postupn\u011b p\u0159\u00edsn\u011bj\u0161\u00edmi emisn\u00edmi normami, jako jsou normy Euro v Evrop\u011b a normy Tier stanoven\u00e9 Agenturou pro ochranu \u017eivotn\u00edho prost\u0159ed\u00ed (EPA) ve Spojen\u00fdch st\u00e1tech.<\/p>\n\n\n\n

                Z\u00e1v\u011br<\/strong><\/h2>\n\n\n\n

                Ten\/Ta\/To t\u0159\u00edcestn\u00fd katalyz\u00e1tor<\/strong> je neop\u011bvovan\u00fdm hrdinou modern\u00ed automobilov\u00e9 technologie. Je to sofistikovan\u00fd z\u00e1vod na chemick\u00e9 zpracov\u00e1n\u00ed v miniatu\u0159e, kter\u00fd prov\u00e1d\u00ed komplexn\u00ed soubor reduk\u010dn\u00edch a oxida\u010dn\u00edch reakc\u00ed. Vyu\u017eit\u00edm s\u00edly platiny, palladia a rhodia transformuje toxick\u00fd proud v\u00fdfukov\u00fdch plyn\u016f z motoru na p\u0159ev\u00e1\u017en\u011b ne\u0161kodn\u00e9 plyny. Jeho v\u00fdvoj byl p\u0159\u00edmou a \u00fa\u010dinnou reakc\u00ed na rostouc\u00ed environment\u00e1ln\u00ed krizi. Zat\u00edmco budoucnost dopravy m\u016f\u017ee spo\u010d\u00edvat v elektromobilech, spalovac\u00ed motor z\u016fstane po cel\u00e1 desetilet\u00ed p\u0159evl\u00e1daj\u00edc\u00ed. Dokud tomu tak bude, bude neust\u00e1l\u00e9 zdokonalov\u00e1n\u00ed a pou\u017e\u00edv\u00e1n\u00ed t\u0159\u00edcestn\u00e9ho katalyz\u00e1toru nezbytn\u00e9 pro ochranu ovzdu\u0161\u00ed, kter\u00e9 d\u00fdch\u00e1me, a zdrav\u00ed na\u0161\u00ed planety.<\/p>","protected":false},"excerpt":{"rendered":"

                Prozkoumejte na\u0161eho kompletn\u00edho pr\u016fvodce t\u0159\u00edcestn\u00fdmi katalyz\u00e1tory: seznamte se s jejich sou\u010d\u00e1stmi, chemick\u00fdmi reakcemi a kl\u00ed\u010dovou rol\u00ed v modern\u00edch vozidlech.<\/p>","protected":false},"author":1,"featured_media":1807,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"googlesitekit_rrm_CAowgdPcCw:productID":"","footnotes":""},"categories":[98],"tags":[103,112,104,106,109,110,32,111,102,107,101,108,105,113,100,99],"class_list":["post-1794","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-guide","tag-3-way-catalytic-converter","tag-automotive-catalyst","tag-car-emissions-control","tag-catalytic-converter","tag-catalytic-converter-function","tag-cold-start-emissions","tag-exhaust-system","tag-how-catalytic-converters-work","tag-nox-reduction","tag-oxidation-catalyst","tag-palladium","tag-platinum","tag-reduction-catalyst","tag-rhodium","tag-stoichiometric-ratio","tag-three-way-catalytic-converter-2"],"_links":{"self":[{"href":"https:\/\/3waycatalyst.com\/cs\/wp-json\/wp\/v2\/posts\/1794","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/3waycatalyst.com\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/3waycatalyst.com\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/3waycatalyst.com\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/3waycatalyst.com\/cs\/wp-json\/wp\/v2\/comments?post=1794"}],"version-history":[{"count":0,"href":"https:\/\/3waycatalyst.com\/cs\/wp-json\/wp\/v2\/posts\/1794\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/3waycatalyst.com\/cs\/wp-json\/wp\/v2\/media\/1807"}],"wp:attachment":[{"href":"https:\/\/3waycatalyst.com\/cs\/wp-json\/wp\/v2\/media?parent=1794"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/3waycatalyst.com\/cs\/wp-json\/wp\/v2\/categories?post=1794"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/3waycatalyst.com\/cs\/wp-json\/wp\/v2\/tags?post=1794"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}