Mitsui Mining & Smelting Develops Silver Catalyst of Diesel Engine

Mitsui Mining & Smelting announced on Wednesday the firm developed diesel engine exhaust catalyst using silver as substitution for platinum. The new catalyst realizes 90% lower cost for precious metals while it represents same performance to purify particulate matters (PM) as platinum. Mitsui Mining & Smelting initially plans to sell the new catalyst for diesel engines adopted into industrial machines, on which restrictions will be strengthened in Japan, USA and Europe after 2012. The firm aims the production at 170,000 units per year and the sales at 9 billion yen per year. In future the firm will expand the supply to trucks and passenger cars.Diesel engines purify exhaust gas by combination of oxidation catalyst and ceramic filter called diesel particulate filter (DPF). Mitsui Mining & Smelting developed silver based catalyst to paste on DPF and burn out PM at low temperatures. For oxidation catalyst, platinum is used.The new catalyst includes silver and cerium based metallic composite oxide. Mitsui Mining & Smelting developed a technology to stabilize silver even under high temperatures at around 800 degrees Celsius. The firm also confirmed the PM burning performance as same as platinum catalyst by testing with actual engines.