Several million tonnes of waste glass are produced throughout Europe and only a part of it can be recycled.
Hence, large quantities of waste glass are delivered to China and other regions where they are utilized as hardcore filling materials for road construction. It has been discovered that waste container glass that cannot be recycled can be used to clean polluted groundwater.
Nichola Coleman from the University of Greenwich has currently developed a simple method to convert waste glass or cullet into tobermorite, a hydrated calcium silicate mineral. The mineral is produced in the phase-pure 11-angstrom form and it can be utilized as an ion-exchange material to remove toxic cadmium and lead ions from contaminated groundwater or waste water streams.
A mixture of cullet, caustic soda and lime is heated to 100⁰ C in a sealed Teflon box and this results in the creation of the tobermorite synthetic mineral. Several tests have shown that removal of cadmium and lead from the solution is very slow. Hence, Coleman recommends the use of synthetic mineral in the in situ groundwater remediation instead of the ex situ industrial effluent filtration processes.
The sorbent derived from waste container glass can be used in reactive barriers to eliminate pollutants in groundwater rather than using it as a remediation solution for waterways.
Source: http://www.inderscience.com/