What is a three-way catalytic converter?
What is a 3 way catalytic converter? A catalytic converter is a device used in emissions control systems. A 3 way catalytic converter oxidizes carbon monoxide and hydrocarbons, and reduces nitrogen oxides. Catalytic converters can be used in internal combustion engines fueled by gas or diesel.
What does a three-way catalytic converter reduce?
A three-way catalyst oxidizes exhaust gas pollutants – both hydrocarbons (HC) and carbon monoxide (CO) – and reduces nitrogen oxides (NOx) into the harmless components water (H2O), nitrogen (N2), and carbon dioxide (CO2).
What are the major composition of 3 way catalytic converter?
The three-way catalytic converter is a multi-component material and is composed of precious metals like rhodium, platinum, palladium, and some metal oxides. A ceramic monolith of cordierite (2Mg. 2Al2O3. 5SiO2) is used because it can withstand high temperatures in the exhaust.
Why is it called three-way catalytic converter?
It is called a catalytic converter because it converts CO into ubiquitous CO2 and NOX into N2and O2 through chemical reactions on a solid catalyst.
How does a catalytic converter work chemistry?
Catalytic converters use reduction and oxidation (redox) reactions to reduce harmful emissions. They use a reduction catalyst composed of platinum and rhodium. It helps reduce nitrogen oxides (NOx) by removing nitrogen atoms from nitrogen oxide molecules (NO and NO2). This lets the free oxygen form oxygen gas (O2).
What is the main difference between two way and three-way catalytic converter?
The first two jobs are basically the same as it still oxidizes carbon monoxide to carbon dioxide and still oxidizes unburnt hydrocarbons to carbon dioxide and water but the new third job is that it separates the nitrogen oxides to nitrogen and oxygen.
What is a catalytic converter ks3?
Catalytic converters These help reduce the release of toxic gases from the exhaust pipe. They contain platinum and rhodium, which act as catalysts. The reactions in catalytic converters: convert carbon monoxide (which is toxic) into carbon dioxide. convert nitrogen oxides (which cause acid rain) into nitrogen and …
Do catalytic converters remove hydrocarbons?
Catalytic Converters. As the name implies, catalytic converters contain catalysts. The catalyst promotes the oxidation of CO and hydrocarbons (see Equations 1 and 2, below), and the reduction of nitrogen oxides (Equation 3, below).
Who invented the three-way catalytic converter?
John Mooney
John Mooney is the co-inventor of the three-way catalytic converter, a small exhaust-cleaning device that hangs beneath about 80 percent of automobiles. Each converter destroys about 98 percent of a car’s three most noxious emissions — simultaneously.
What substance is in catalytic converters?
The catalyst component of a catalytic converter is usually platinum (Pt), along with palladium (Pd), and rhodium (Rh). All three of these platinum group metals, or PGMs, are extremely rare but have a broad range of applications in addition to catalytic converters.
How does a three-way catalytic converter work?
In practice, three-way catalysts are used with air to fuel ratio controllers which maintain the mixture composition at stoichiometric. These controllers utilize a feedback signal from the oxygen sensor positioned in front of the catalyst in the exhaust system.
What are the thermodynamics of catalytic converters?
Thermodynamics of catalytic converters 1 Reduction of nitrogen oxides into elemental nitrogen and oxygen: (7.1.4) N O x → N x + O x 2 Oxidation of carbon monoxide to carbon dioxide. (7.1.5) C O + O 2 → C O 2 3 Oxidation of hydrocarbons into carbon dioxide and water. (7.1.6) C x H 4 x + 2 x O 2 → x C O 2 + 2 x H 2 O
How do chemical reactions occur in a three-way catalyst?
One of the fundamental chemical reactions occurring in the three-way catalyst can be written as follows: Concentrations of pollutants in the exhaust gas depend on the fuel mixture composition. At lean fuel mixtures the exhaust gases contain little carbon monoxide or hydrocarbons but high concentrations of NO x.
What is the difference between lean and rich catalytic converters?
There are two types of “systems” running in a catalytic converter, “lean” and “rich.” When the system is running “lean,” there is more oxygen than required, and the reactions therefore favor the oxidation of carbon monoxide and hydrocarbons (at the expense of the reduction of nitrogen oxides).