Nanostellar, Inc. has announced a first in diesel emissions technology: the introduction of gold as an oxidation catalyst. Nanostellar's NS Gold catalyst enables manufacturers of light- and heavy-duty diesel engines to reduce noxious emissions by as much as 40 percent more than existing pure-platinum catalysts at equal cost. Nanostellar introduced its first-generation product, based on a platinum and palladium alloy, in mid-2006, and it achieved 25%-30% higher performance than commercial pure-platinum catalysts. NS Gold, Nanostellar's second-generation product, delivers a further 15%-20% performance increase.
Platinum is the most expensive component of the diesel oxidation catalysts (DOCs) that are required to meet the new, stringent emission regulations for the 14 million light-duty and 2 million heavy-duty diesel vehicles produced annually worldwide. In recent years, Nanostellar and other producers of catalyst materials have introduced the use of palladium to partially replace the four-times more expensive platinum. Now, to further reduce the amount of platinum needed and the overall cost of the catalysts, Nanostellar has pioneered the use of gold -- which is currently about half the price of platinum -- for diesel emission control.
Independent testing of Nanostellar's NS Gold, in comparison with today's pure-platinum catalysts, has shown that NS Gold increases hydrocarbon oxidation activity by as much as 40 percent at equal precious-metal cost. When compared to emerging platinum-palladium catalysts, NS Gold promises to increase hydrocarbon oxidation activity by 15-20 percent at equal precious-metal cost. A tri-metal formulation of gold, platinum, and palladium, NS Gold allows the proportions of each metal to be adjusted to help catalyst systems engineers meet engine-specific performance targets and stabilize the overall cost of diesel catalysts, despite fluctuations in the price of precious metals.
"Not only does NS Gold break performance barriers imposed by mixed platinum and palladium catalysts, but also its performance can be more easily tuned to the characteristics of a variety of diesel engines," said Pankaj Dhingra, CEO of Nanostellar. "We are excited to offer NS Gold to improve the cost equation for the diesel industry. Gold is not new to catalyst scientists, but this is the first time it has been successfully adapted for use in automotive diesel oxidation catalysts."
According to Dhingra, the continued evolution and maturity of Nanostellar's Rational Catalyst Design methodology brought NS Gold into existence in record time. "Rational Design combines computational approaches with targeted experiments to accelerate the development of new materials," he explained "Nanostellar has over 50 man-years of Rational Catalyst Design experience and a substantial database of catalyst-specific knowledge, developed from both computational and experimental approaches. We have unique algorithms and software that address computational catalyst design, along with proprietary synthesis technologies and novel testing methods that provide a detailed understanding of catalytic processes."
NS Gold is potentially suitable for treating all lean-stream exhaust, where air is in excess of fuel-borne hydrocarbon gases. Applications include, but are not limited to, treating particulates and hydrocarbons in soot filters, stationary-source volatile organic compound (VOC) emissions, and ammonia slip in selective catalytic reduction (SCR) systems.
NS Gold is immediately available for targeted application-specific testing. Production quantities will be available as production programs are identified and released.