New emissions standards are driving the development of smaller and cheaper catalysts.
|JMI Technical Director Christopher Bennett says precious metal content in catalysts is shrinking.|
Q. What do you see as the major challenge for automotive catalysts over the next few years?
A. I would say that new emission standards, primarily Tier 2, LEV 2 and PZEV, are currently driving the development of automotive catalysts. These standards are aimed at reducing hydrocarbon and nitric oxide emissions from vehicles. These two emissions are responsible for smog formation at ground level, creating breathing problems for people in inner cities. In particular, the need for SUVs and light trucks to meet these standards at the same level as passenger cars is considered to be a challenging objective. We have development programs in place to meet these objectives.
Q. Are there any other significant challenges?
A. At the same time technology is being developed to meet these new standards there is a very strong desire to reduce the cost of all automotive components. This is especially the case for “hidden” components such as the automotive catalyst that do not ostensibly add value to the vehicle in the eyes of the end customer. One of the principle costs in the automotive catalyst is the precious metal that drives the reaction of harmful gases to water, nitrogen and carbon dioxide. Although precious metals have generally reduced in value (the price of platinum remains high) they still form a substantial cost component. In addition to precious metal and catalyst volume, catalyst complexity also drives the cost of the aftertreatment system. So the desire is to meet new regulations at the lowest cost possible.
Q. What role does Johnson Matthey play in the process of meeting the new emission targets?
A. Over the last seven years, Johnson Matthey Inc. (JMI) has focused on both developing and applying catalyst technology to specific vehicles. This effort has developed into a tremendously successful partnership between JMI and our customers, allowing a much higher level of information sharing than previously existed. With access to customer’s future model year vehicle and engine technology, JMI has been able to design aftertreatment systems with our customers and provide data that supports the use of low cost aftertreatment systems. As a catalyst company, we are able to understand the effects of different calibration strategies on our catalysts, and the effect of catalyst design and precious metal content on the emissions from a given vehicle. This allows us to design systems and catalysts at ever-lower precious metal content.
Q. You have mentioned precious metals as a key component of cost. How low of a level have you reached?
A. We have described some of our most recent catalysts as “almost metal free.” By that we mean where a given catalyst in a system may have contained $25 in precious metal at today’s prices, the combination of advanced engine control and improved catalyst technology has enabled as little as $1 to be used — sometimes with an additional reduction in the volume of catalyst in the exhaust.
Q. Presumably these new catalysts cost more money than the current generation?
A. Actually, no. Because we are able to use a single precious metal in these catalysts, and not very much of it, we are able to dramatically simplify the catalyst design. This means that in the manufacturing process the number of processing steps has (been) reduced significantly. This obviously reduces the manufacturing cost and product price.
Q. Are you able to meet the new standards you mentioned earlier with this technology?
A. We have recently generated data in our labs in Pennsylvania demonstrating Tier 2, Bin 5 emissions with this catalyst technology. The systems that we have been testing have substantially less volume, less precious metal and lower catalyst manufacturing cost compared with previous systems designed to meet less challenging emissions standards.
Q. And this is done through improved catalyst technology?
A. The work I described was done using production engine technology. However, this improved catalyst technology is best utilized with advanced engine control. It really is important not to underestimate the value and role of the calibration engineer, and the synergy derived from the catalyst scientist and calibration engineer working together.