Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: TUESDAY, July 19, 1994 TAG: 9407190034
SECTION: CURRENT PAGE: NRV1 EDITION: NEW RIVER VALLEY
SOURCE: DAVID REED ASSOCIATED PRESS
DATELINE: BLACKSBURG LENGTH: Medium
``The trend is to move away from mercury,'' said Keith Vanderbosch, vice president of engineering for American Electrical Components. ``It's becoming more and more distasteful to the world.''
AEC, an Indiana company that makes about 30 million mercury switches a year, is trying to develop Virginia Tech's prototypes so they can be mass produced on its assembly line, Vanderbosch said last Friday.
``We think it has pretty good applicability,'' he said.
Mercury, also known as quicksilver, flows within glass and steel tubes and conducts electricity, so it's used in switches that turn on and off based on position. They turn on lights when you open the trunk of cars, turn off space heaters when they fall over and turn off steam irons when they're left on too long. They regulate sewage and plumbing pumps and control french fryers. Mercury also is used in 90 percent of the nation's thermostats and in an L.A. Gear children's sneaker with lights that flash each time you hit the ground.
But in the environment, the metallic chemical element is changed into toxic compounds. Several states have passed laws recently restricting the disposal of products that contain mercury while California, Florida and Minnesota have restrictions on the sale of new products with mercury.
L.A. Gear Inc. is exploring the use of the Virginia Tech prototypes, according to Clay Kahlor, a Virginia Beach consultant negotiating the deal. L.A. Gear announced last Wednesday that it will pay Minnesota $70,000 to help recycle lighted athletic shoes that state officials claimed are a toxic waste hazard because they contain mercury.
When cars are crushed and products containing mercury are compacted and sent to landfills, mercury can leak into the soil and water. Even tiny amounts of mercury can contaminate fish and, when eaten, cause serious damage to the central nervous system, especially in small children and fetuses.
The term ``mad as a hatter'' came from people who used mercury to tan hats, said Carlos Perry, a Manassas plumbing supply salesman. When he began losing business because his products contained mercury switches, Perry pursued the idea of replacing mercury with another liquid conducting material.
Perry said he sought research funding from the EPA, but the agency wrote him and said, ``there is no scientific evidence it is possible to do it, which is paradoxical because that's what research is all about.''
Perry contacted his local legislator, who contacted Virginia's Center for Innovative Technology, an economic development agency that matches industry needs with university researchers.
CIT agreed within a few days to cosponsor the research by chemistry professors James Rancourt and Larry Taylor.
Rancourt said he also was skeptical initially. ``I didn't think it would work. It seemed to me the kind of thing that would have been done a long time ago. But we said we'd give it a try.''
Rancourt and an assistant needed a metal that would stay in liquid form in subfreezing temperatures, but they ruled out using tin or any other material that becomes toxic in the environment. They had tested more than 50 liquid metal alloys in ice baths when he came up with something like the legendary laboratory mistake invention - the one where a test tube spills and a new drug is discovered.
There was a contradiction in the standard handbooks on chemistry and physics. One said the metal alloy would, in liquid form, coat glass rather than form a bead like mercury does, he said. ``Another book I found ... suggested the material should behave just like mercury. The error was due to an impurity that people think is going to be there. Once we figured that out, a whole lot of dominos started falling.''
The patent is pending, so Rancourt and others involved with the material said they could not specifically identify it.
``Because we're chemists, not metallurgists, we did some things you're not supposed to do,'' Rancourt said. ``And we were kind of lucky. There's a million possible combinations of materials and you can't test them all.''
CIT underwrote the patent process and licensed the technology to NonMerc, a company Perry formed to commercialize the product.
Rancourt said he's received several calls from company engineers that Perry has approached. ``They would like to believe him but don't, and they ask me, `Have you really done the following,' and I say yes, we have.''
by CNB