A new technique for reducing waste from chemical processes involved in everything from petroleum refining to pharmaceutical manufacturing also may hold the key to cleaning up radioactive remains at eastern Washington's Hanford nuclear site.
Using elect ricity, instead of concentrated chemicals, to drive a key step in many chemical separation processes could greatly reduce waste byproducts, says Dan Schwartz, a University of Washington chemical engineering professor who is exploring ways to improve this environmentally friendly approach for a variety of scientific and industrial applications.
Schwartz and a team of four undergraduate and graduate students are collaborating with scientists at Pacific Northwest National Labo ratories who are pilot testing the new process for use in radioactive waste cleanup efforts at Hanford. Schwartz also is teaching an interdisciplinary laboratory course on the technique this quarter as part of a major UW effort to integrate leading-ed ge research on environmental technology into the undergraduate curriculum.
"Environmentally-benign chemical processing is an area of growing importance for chemical industries, and it's being driven as much by economics as by regulation," Schwartz s ays. "If you don't produce waste, you're using your raw materials more efficiently and you're not paying for disposal."
A significant amount of waste generated by industry and at Hanford occurs in recharging ion exchange systems which are used to separa te the byproducts of chemical and nuclear processes. Traditional ion exchange systems employ charged compounds to attract specific chemicals with opposite charges in order to remove them from a solution.
In water softening, for example, a negativel y-charged ion exchange material acts
like a sponge for positively-charged calcium ions in hard water. Eventually, however, the
ion exchange material becomes filled with calcium and must be regenerated by a series of chemical
Contact: Greg Orwig
University of Washington