Pt Pd Rh Three-Way Catalytic Converter For Car Exhaust

Material:Cordierite and stainless steel
Size:Diameter: 80-144mm Length: 70-152mm (Customizable)
Shape :Round, Oval,Racetrack-shaped
Application :Auto Exhaust System

Specification
FAQs

Pt Pd Rh Three-Way Catalytic Converter For Car Exhaust

The three-way catalytic converter is the most important external purification device installed in the automobile exhaust system. The three-way catalytic reactor is similar to a muffler. Its outer surface is made of double-layer stainless steel sheet in a cylindrical shape. A heat-insulating material-asbestos fiber felt is installed in the double-layer sheet sandwich. Inside, there is a purifying agent in the middle of the mesh partition. The purifying agent is composed of a substrate and a catalyst. The main function of the 3 way catalytic converter is to convert harmful gas into harmless gas, which plays a role in protecting the environment. It is installed in the exhaust pipe of a car, close to one end of the engine. After the exhaust gas is discharged, it is converted through three-way catalysis. After the exhaust gas is converted, it is discharged outside the car.

Product Feature:

1. Good low tempreture light off performance (T50 ≤ 180 ℃ ).

2. Higher conversion rate (CO,THC,SOF ≥ 97%).

3. Precious metals & rare earth compound catalyst technology provides the high oxygen storage and high stability catalyst.

4. Precise control of precious metals and other materials during catalyst manufacturing process.

5. Vehicle complete system matching technology and systematic solutions for the customer.

6. Up to Euro VI Emission Standard.

Technical Advantages:

1. Good low tempreture light off performance (T50 ≤ 180 ℃ ).

2. Higher conversion rate (CO,THC,SOF ≥ 97%).

3. Precious metals & rare earth compound catalyst technology provides the high oxygen storage and high stability catalyst.

4. Precise control of precious metals and other materials during catalyst manufacturing process.

5. Vehicle complete system matching technology and systematic solutions for the customer.

6. Up to Euro VI Emission Standard.

Product Paramenters

Product name	Three-way Ceramic Catalyst converter
Material	Cordierite and stainless steel
Size	Diameter: 80-144mm Length: 70-152mm (Customizable)
Working Temperature	150°C-1200°C
Shape	Round, Oval,Racetrack-shaped
Cell Density	400-600 CPSI (customizable)
Application	Auto Exhaust System
Emission Standard:	Euro 3/4/5/6
Model:	Universal

Specification Size

Specification	Diameter (mm)	Length (mm)	Cell Density (CPSI)	Emission Standard
Ø80*60	80	60	200/300/400/600	Euro 3/4/5/6
Ø93*60	93	60	200/300/400/600	Euro 3/4/5/6
Ø93*75	93	75	200/300/400/600	Euro 3/4/5/6
Ø93*88.3	93	88.3	200/300/400/600	Euro 3/4/5/6
Ø93×101.6	93	101.6	200/300/400/600	Euro 3/4/5/6
Ø101.6*60	101.6	60	200/300/400/600	Euro 3/4/5/6
Ø101.6*76.2	101.6	76.2	200/300/400/600	Euro 3/4/5/6
Ø101.6*90	101.6	90	200/300/400/600	Euro 3/4/5/6
Ø101.6*100	101.6	100	200/300/400/600	Euro 3/4/5/6
Ø101.6*118	101.6	118	200/300/400/600	Euro 3/4/5/6
Ø101.6*123.3	101.6	123.3	200/300/400/600	Euro 3/4/5/6
Ø101.6*136	101.6	136	200/300/400/600	Euro 3/4/5/6
Ø101.6*152.4	101.6	152.4	200/300/400/600	Euro 3/4/5/6
Ø103*130	103	130	200/300/400/600	Euro 3/4/5/6
Ø105.7*100	105.7	100	200/300/400/600	Euro 3/4/5/6
Ø105.7*115	105.7	115	200/300/400/600	Euro 3/4/5/6
Ø105.7*130	105.7	130	200/300/400/600	Euro 3/4/5/6
Ø105.7*147.5	105.7	147.5	200/300/400/600	Euro 3/4/5/6
Ø105.7*152.4	105.7	152.4	200/300/400/600	Euro 3/4/5/6
Ø118.4*90	118.4	90	200/300/400/600	Euro 3/4/5/6
Ø118.4*100	118.4	100	200/300/400/600	Euro 3/4/5/6
Ø118.4*101.6	118.4	101.6	200/300/400/600	Euro 3/4/5/6
Ø118.4*114.3	118.4	114.3	200/300/400/600	Euro 3/4/5/6
Ø118.4*120	118.4	120	200/300/400/600	Euro 3/4/5/6
Ø118.4*123.3	118.4	123.3	200/300/400/600	Euro 3/4/5/6
Ø118.4*127	118.4	127	200/300/400/600	Euro 3/4/5/6
Ø118.4*136	118.4	136	200/300/400/600	Euro 3/4/5/6
Ø118.4*138	118.4	138	200/300/400/600	Euro 3/4/5/6
Ø118.4*152.4	118.4	152.4	200/300/400/600	Euro 3/4/5/6
Ø132.1*127	132.1	127	200/300/400/600	Euro 3/4/5/6
Ø132.1*146	132.1	146	200/300/400/600	Euro 3/4/5/6
Ø143.8*101.6	143.8	101.6	200/300/400/600	Euro 3/4/5/6
Ø143.8*152.4	143.8	152.4	200/300/400/600	Euro 3/4/5/6
Remark:	Other sizes can be customized according to customer requirements.

Working Principle

TWC Three Way Catalyst

A three-way catalyst can cut CO, HC and NOx by over 99% if the air to fuel ratio is accurately controlled. Three-way catalysts will only give full conversion of each of these three pollutants in a gas stream containing a stoichiometric ratio of CO and NOx.

FAQ-Pt/Pd/Rh Three-Way Catalytic Converter for Car Exhaust

Q1. What is a three-way catalytic converter and what does it do?

A three-way catalytic converter (TWC) is an emissions control device in gasoline vehicle exhaust systems. It uses precious metal catalysts to simultaneously convert three harmful pollutants—CO, HC, and NOx—into harmless substances. Conversion efficiency can reach over 90% under optimal conditions.

Q2. What are the roles of each precious metal?

Metal	Primary Function
Platinum (Pt)	Oxidizes CO and HC; excellent for low-temperature ignition and high-temperature stability
Palladium (Pd)	Oxidizes CO and HC; strong oxidation activity
Rhodium (Rh)	Essential for reducing NOx; prevents harmful byproducts

While Pt and Pd handle oxidation, Rh is the key metal for NOx conversion. Without Rh, NOx reduction efficiency drops significantly.

Q3. How does the converter work?

Two critical conditions must be met for maximum efficiency:

Precise air-fuel ratio: Engine must operate near the stoichiometric point (~14.7:1). Oxygen sensors monitor exhaust and the ECU adjusts fuel injection in a closed-loop system
Operating temperature: Requires "light-off" temperature of approximately 250–400°C to become active. Cold-start emissions remain a major challenge

Q4. What is the converter made of?

A TWC consists of three main components:

Metal housing: Stainless steel with heat insulation
Ceramic substrate: Honeycomb structure (typically 400–600 CPSI) providing large surface area with low flow resistance
Catalytic coating: Pt/Pd/Rh precious metals on a washcoat layer (alumina, ceria-zirconia) with oxygen storage capability

Ceramic honeycomb substrates are used in over 90% of vehicles, with cordierite being the most common material.

Q5. What causes converter failure?

Failure Type	Cause
Thermal aging	High-temperature exposure (>900°C) from engine misfire or rich mixture
Chemical poisoning	Lead, sulfur, or phosphorus in fuel/oil – causes permanent deactivation
Physical clogging	Substrate melting, fragmentation, or carbon deposits
Oxygen sensor failure	Faulty sensors disrupt closed-loop control

Warning sign: Check Engine Light with P0420/P0430 code ("Catalyst efficiency below threshold").

Q6. What is the benefit of combining all three metals?

Synergy: Each metal complements the others across the full engine operating range
Enhanced stability: Pt improves high-temperature durability; maintains N₂ selectivity after aging
Broader temperature window: Pt/Rh handles low-temperature activity; Pd/Rh covers mid-to-high temperature oxidation
Balanced performance: Achieves over 95% conversion of all pollutants under optimized conditions

Q7. What maintenance and usage precautions should I follow?

Use unleaded fuel only – Lead causes permanent poisoning
Avoid engine misfires – Unburned fuel can overheat and destroy the catalyst
Keep engine properly tuned – Misfiring or backfiring damages the converter
Use quality fuel – Sulfur and impurities accelerate poisoning
Check O₂ sensors regularly – Ensure closed-loop fuel control is functioning

Q8. What are current development trends?

GPF integration: Combining TWC with gasoline particulate filters for particle control
Low-precious-metal technology: Reducing Pt/Rh content through improved dispersion and substrate design
Electrically heated catalysts: Rapid heating to address cold-start emissions (key for future China 7 standards)
Enhanced oxygen storage: Optimized ceria-zirconia composites for better air-fuel ratio buffering