With the improvement of the living standards of mainland residents, more and more families have private cars, according to statistics, the mainland by the end of 2021, the number of motor vehicles in the country reached nearly 400 million, car drivers 444 million people. Although there are many people driving, there are certainly many people who do not know that there is a more valuable part of the car, that is, the ternary catalyst in the exhaust of the car. In order to make a profit, some criminals have begun to use their brains, in addition to stealing car oil and goods, now even the ternary catalyst of the car has begun to focus.
For example, Guangxi recently caught a gang of thieves who stole ternary catalysts, using deck cars to steal in different places, one of them was responsible for looking at the wind, and the other two were responsible for stealing the ternary catalyst on the spot.
In addition, there are some people who focus on sharing cars, criminals will share cars to start a suitable crime site, and then remove the three-way catalyst on the car, steal the three-way catalyst in the catalyst, and then install the catalyst, these criminals after stealing to a certain number, they will sell these three-way catalysts at a high price. So what exactly is a ternary catalyst for cars, and why is it so valuable?
What is a ternary catalyst?
We know that fuel vehicles mainly use gasoline or diesel as fuel, but gasoline or diesel will produce a large amount of exhaust gas after combustion, including some gases that pollute the air, such as CO, HC, NOx, etc. If these exhaust gases are directly emitted, it will have a greater impact on the air, and with the improvement of the exhaust emission standards of automobiles in various countries, these exhaust gases must be treated and emitted, so the three-way catalyst began to be applied in automobiles.
The ternary catalyst is mainly composed of a carrier, coating and active substance, the carrier is honeycomb-like ceramic iolite, the surface is coated with a highly active γ-Al2O3 coating, used to increase the surface area, the catalytic activation component is platinum, palladium and rhodium and other platinum group metals (PGM), these metals are highly dispersed in the coating with a particle size of 1 to 10 nm. At high temperatures, the CO, HC and NOx harmful gases in the exhaust gas will come into contact with the surface of the active metal platinum palladium rhodium when passing through the catalyst hole, and at the same time trigger a catalytic reaction, and these harmful gases will react with each other to redox reactions, resulting in non-toxic and harmless carbon dioxide, nitrogen and water.
Due to the large specific surface area of the catalyst of this structure, the resistance to the air flow is small, which does not hinder the emission of exhaust gas, and the catalytic efficiency is high, and most of the automotive catalysts used in continental automobiles are currently used in this structure.
Because this catalytic converter can simultaneously convert the three main harmful substances in the exhaust gas into harmless substances, it is also called a three-way catalytic converter.
Ternary catalyst for the exhaust gas treatment of automobile emissions has a very important role, and exhaust emissions are a very important one of the vehicle detection indicators, many cars with a long use of the year in the annual inspection, exhaust emissions will appear substandard phenomenon, then this time need to replace the ternary catalyst, but the price of a ternary catalyst can not be cheap, the price from thousands to tens of thousands.
Expensive rare precious metals in automotive ternary catalysts
The reason why automotive catalysts are so expensive is mainly due to the scarcity of catalytic metals used in catalysts, and the catalytic metals used in ternary catalysts are mainly platinum group metals. Platinum group metals include ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir), platinum (Pt) six metal elements, platinum group metal refining is also very complex.
Platinum group metals
Due to the surge in automobile sales in recent years, the market demand for platinum group metals has been greatly promoted, and the annual increase in automobiles has reached more than 90 million units, of which the platinum group metals used for automobile catalysis have soared from the original 2.2 million ounces per year to 13.8 million ounces per year. Generally speaking, the total amount of three rare precious metals in the catalyst used in a car is about 1.5-2 grams, of which the price of platinum and palladium is relatively cheap, between 200-400 yuan per gram, but the price of rhodium is very high, and the current rhodium price can reach more than 4,000 yuan per gram, which is equivalent to more than ten times the price of gold.
Rhodium metal
The global platinum group metal content is very small, with a total reserve of about 70,000 tons, and even platinum ore has a very low platinum content. The platinum content in each ton of raw ore is only a few grams, and the rhodium metal content is even less. Most of the world's platinum group metal reserves are distributed in South Africa, and the rest are mainly in Russia, the United States and Canada, which account for more than 90% of the world's platinum reserves.
At last
Usually thieves will be stolen ternary catalyst sold to the middleman, the intermediary will be sold directly to the car repair shop or recycled, because the ternary catalyst is a more important part of the car, once stolen, the car exhaust emissions are likely to face exceeding the standard, in our unknowing case of let the car exhaust "naked" may also face fines, so as the owner of the car, usually we should have more than one eye.
Generally speaking, when the three-way catalyst in the car is stolen, the sound of the car exhaust will become very loud, especially when starting, the vibration of the exhaust pipe exhaust cylinder will be intensified, and the exhaust cylinder will emit a sound similar to that of the old-fashioned tractor.
In addition, we can also make a certain judgment by smell or smoke color, because the catalyst in the three-way catalytic converter can effectively reduce the odor and particulate matter of the vehicle exhaust, if the vehicle's waste odor channel becomes thick and has black smoke at the same time, then it is also possible that the three-way catalytic converter in the car has been stolen, and at this time we have to check.
Usually, if it is a long time to stop, it is also best to park the car in a monitored area to prevent thieves from staring at our car.