Latest Issue of Science News


Start your engines

An automotive system designed to reduce toxic hydrocarbon emissions has received the checkered flag from mechanical engineers who examined the device.

Once an engine reaches its operating temperature, catalytic converters eliminate nearly all hydrocarbon emissions. However, in the first 2 minutes after a car is started, some toxic fuel doesn't burn entirely and gets spit out the exhaust pipe. Up to 95 percent of a vehicle's hydrocarbon emissions occur during this warm-up period.

In 2001, a group of engineers developed a lightweight, inexpensive system, called the on-board distillation system, that converts regular fuel into a highly volatile distillate that vaporizes more easily as the engine warms up (SN: 1/20/01, p. 39: Simple system may curb auto emissions). This start-up fuel is kept in a separate tank that's accessed only during the first 20 seconds after ignition.

Note: To comment, Science News subscribing members must now establish a separate login relationship with Disqus. Click the Disqus icon below, enter your e-mail and click “forgot password” to reset your password. You may also log into Disqus using Facebook, Twitter or Google.

This article is available only to subscribing members. Join SSP today or Log in.