Why thieves are likely to target the exhaust pipes of your cars

Owners of high end automobiles have every reason to be worried as thugs now target valuable rare metals found in vehicle exhaust pipes that can be used for making explosives.

The network that involves mechanics, car dealers and shadowy foreign wealthy buyers is said to extract the metals from catalytic converters in the exhaust systems.

These can then be used in the manufacture of infra-red detectors used by the military and in making explosives.

The criminals have been targeting high-end cars and commercial trucks taken by their owners for repairs. In fact most might be unknowingly driving vehicles whose catalytic converters, meant to reduce noxious fumes, have been removed by unscrupulous mechanics, thus polluting the environment.

Some of the people involved in the illegal trade have revealed that the lucrative prices for the rare earth metals found in the devices, including rhodium, palladium, cerium and platinum, are irresistible.

The racket is not only exposing innocent people to noxious vehicle exhaust fumes but allowing criminals easy access to explosives-making material.

These rare earth metals convert as much as 90 per cent of the harmful gases in automobile exhaust, including hydrocarbons, carbon monoxide and nitrogen dioxide, into less noxious substances such as nitrogen, carbon dioxide and water vapour.

 The rare earth metals in catalytic converters are a sort of sieve that cleans the exhaust fumes into manageable levels.

Those involved in the theft are targeting vehicles taken to garages and insurance salvage yards. Most of the written off vehicles are most susceptible.

Figures do not reveal the exact type of cars that the thugs in Dar es Salaam who have stopped stealing unprofitable parts.

 In Nairobi, Ken ya four wheel drive vehicles like Toyota Land Cruisers, Mitsubishi Pajeros, BMWs, Volkswagens, ML and G class Mercedes Benz are mostly targeted because their road clearance makes their exhaust systems easier to access.

Apart from catalytic converters, rare earth metals are also used in polishing jewellery, production of high capacity computer hard drives, refining of petroleum into finished products like petrol, diesel, kerosene among others, manufacture of thermocouples that measure temperature in glass, steel, and infrared detectors used by the military.

Cerium, palladium and rhodium, which are classified as platinum metals, are used in fertilisers and explosives as sieves for the catalytic conversion of ammonia to nitric acid and fabrication of silicone used in aerospace.

They can also be used in medicine as anti-cancer drugs, glass making equipment and in dentistry.

According to online sources, rhodium which is sold at $4,200 per ounce is a silver-white metal alloying agent with high reflectivity of light used in hardening platinum. It is not easily corroded or tarnished by atmosphere at room temperature.

When added to platinum in small amounts, Rhodium forms alloys that are harder and lose weight at high temperatures even more lower than pure platinum.

These alloys are commonly used for laboratory furnace crucibles, spark plug electrodes and catalysts in very hot chemical environments, including automobile catalytic converters.

Another rare metal is palladium which retails at $47,525.23 per Kg but could go higher in the black market.

Wikipedia, an online encyclopedia, describes it as lustrous silver-white metal among the platinum group of metals that have similar chemical properties with the lowest melting point. It is mostly used in catalytic converters.