While you may feel quite virtuous when you leave all your glass containers out for recycling, you might be surprised to know that much of your colored glass won't be used. That's because even though there's a fairly constant demand for recycled clear glass, glass in colors such as green, brown and blue isn't all that sought-after, so many recycling centers don't bother processing it. As a result, waste colored glass is now being stock-piled in some locations, waiting for a use. Thanks to research conducted at the University of Greenwich, however, that glass may soon be used for filtering pollutants out of ground water.

Dr. Nichola Coleman, a senior lecturer in Materials Chemistry, has been leading the research.

Her team combined ground colored glass, lime and caustic soda, then heated the mixture to 100C (212F) in a sealed stainless steel container. This transformed the ingredients into tobermorite, a mineral that is effective at removing heavy metals from ground- or waste-water streams. She is hoping to incorporate the tobermorite into filtration devices, that could be used to prevent water-borne pollutants from spreading from contaminated areas.

"The novelty of the research is that the glass can be recycled into something useful," the U Greenwich researcher stated. "Nobody has previously thought to use waste glass in this way."

A paper on the research was recently published in the International Journal of Environment and Waste Management.