
Nut Shells May Help Industry
Stay Cleaner, Save MoneyBy Jill Lee October 11, 1996NEW ORLEANS, Oct. 11--What
good are nut shells without nuts? They could be an ideal low-cost material for
cleaning heavy metals out of industrial wastewater, a
U.S. Department of Agriculture researcher
says. "We found a way to chemically treat pecan shells so they become
activated charcoal filters, removing not only organic compounds from water, but
also heavy metals," said chemist Chris Toles with USDA's
Agricultural Research Service. "In
tests, for example, the nutshell-based filters absorbed three times more copper
than other types of filters currently on the market." ARS chemist Wayne Marshall at the agency's
Southern Regional Research Centerin New Orleans added producing charcoals from nutshells might cut energy costs
and provide a new market for a product that is typically considered waste. "This could be a real opportunity for small nut producers who are
willing to pool their resources," Marshall said. Some industries, such as metal platers, would still need to filter
wastewater with an ion exchange resin. But using the activated carbons as an
inexpensive pre-filter could extend the life of the resin and reduce filtering
costs. The scientists have applied for a patent on the charcoal-making process,
which involves treating the nut shells with oxidizing agents and heat. A cooperative research and development agreement has been signed with Rio
Grande Environmental Products, LLC, Albuquerque, N.M., a small business
developed to commercialize environmental technologies. The firm intends to fund
a prototype system to demonstrate the commercial viability of the carbons,
according to company executive David Binkley. Scientific contact: Wayne Marshall, Commodity Utilization Research
Unit, ARS, USDA, Southern Regional
Research Center, New Orleans, LA 70179; phone (504) 286-4356, fax (504)
286-4419. U.S. Department of Agriculture | |