The London Time s article on 21^st November 2020 reported that the thefts of catalytic converters  have increased significantly  recently. The police had logged in 14,690 incidents  across Britain this  year, a rise from 2,484 a year earlier and 985 the year before. The rise is believed t have ben driven by  a steep rise in the use of precious metals  in catalytic converters. It has also been linked  to the  growth in popularity of hybrid cars, which tend to contain higher concentration of the precious of the precious metals, and 4 x 4s, whose higher chassis make is make easier for thieves. Criminals can remove the catalytic converter of car in less than a minute using an electric saw.  

Precious metals in catalytic converters

A catalytic converter is a device used to convert toxic vehicle emissions to less toxic harmful substances by way of catalyzed, or accelerated chemical reactions. Most present-day vehicles that run on gasoline, including automobiles,  trucks, trains, motorcycles and planes, have exhaust systems employing catalytic converters. The catalyst component of a catalytic converter is usually  platinum (Pt), along with palladium (Pd), and rhodium (Rh). All the three platinum group metal or PMG are extremely rare but  have a broad range of applications. In addition, to catalytic converter Platinum, for example, is used in laboratory and dental equipment, electrical contacts and electrodes, and jewellery, while Palladium plays a key role in fuel cell technology. With numerous applications, and limited supply these valuable metals are an attractive target for recovery and reuse from spent catalytic converters.

The amounts and proportions of PGMs depends on the age and type of vehicles.

• Car, light trucks, and motorcycles average total 2-6 grammes.
• Larger -engine SUVs and trucks average total can range anywhere from 6 -30 grammes.

Gasoline-powered -vehicle catalytic converters use all three of the rare-earth metals. Diesel-powered -vehicle catalytic converters use only platinum and rhodium.

The average concentration of and the ratio of Pt and Rh were more or less constant 20 years ago, so a simple weighting was sufficient to arrive at a good estimation of the precious metals content. However, the price of these three precious metals has fluctuated strongly over the last twenty years, depending on the supply, demand and speculation.

The Times London article noted that scrap metal dealers  can pay up to BP200 per catalytic converter. The table below the value of the precious metals compared to other metals such as gold and gold.

Metal	BP in gramme	BP in kilogramme
Gold	45.44	45,440
Silver	0.50	500
Platinum	23.36	26,360
Palladium	56.94	56,940
Rhodium	363	363,000

Source: beleyerbullion.co.uk.

The supply and demand for PMGs

Johnson Matthey, which produces a third of all catalytic converters  in the world publishes the Pmg report annually. The latest report published in February 2020 shows the supply and demand situation in 2017, 2018 and 2919, respectively. 

Platinum in thousand oz

Supply	2017	2018	2019
South Africa	4,450	4,467	4,411
Russia	720	687	667
Other	969	956	942
Total supply	6,139	6,110	6,020
Gross demand
Autocatalyst	3,208	2,967	2,913
Jewellery	2,387	2,261	2,082
Industrial	2,038	2,493	2,358
Investment	361	67	1,131
Total gross demand	7,994	7,788	8,484
Recycling	-2,049	-2,098	-2,261
Total net demand	5,945	5,690	6,223
Movements in stocks	194	420	-203

Palladium in thousand oz

Supply	2017	2018	2019
South Africa	2,547	2,543	2,648
Russia	2,452	2,976	2,802
Other	1,452	1,487	1,442
Total supply	6,451	7,006	6,894
Gross demand
Autocatalyst	8,462	8,782	9,677
Jewellery	167	148	140
Industrial	1,820	1,848	1,742
Investment	-386	-574	-57
Total gross demand	10,063	10,204	11,502
Recycling	-751	-77	-1,192
Total net demand	7,202	7,083	8,086
Movements in stocks	-751	-77	-1,192

Rhodium in thousand doz

Supply	2017	2018	2019
South Africa	611	618	621
Russia	78	69	59
Other	70	70	66
Total supply	759	757	746
Gross demand
Autocatalyst	834	877	1,003
Other	207	165	141
Total gross demand	1,041	1,042	1,144
Recycling	-310	-335	-372
Total net demand	731	707	772
Movements in stocks	28	50	-26

Conclusion

The prices of precious metals used in catalytic converters are likely to increase with the popularity of hybrid cars and newer efficient gasoline-cars. Their owners would have to be aware that the exhaust systems would be an open invitation to thieves, as their scrap values are high with every  increase in the price of platinum, palladium and rhodium.