The University of Nottingham has developed a manufacturing process to produce porous microspheres from glass and glass ceramics materials via a single-stage manufacturing process. This single stage process yields highly porous (up to 80%) microspheres in the size range of 25-350 μm, with fully interconnected porosity features (which range in size from microporous to mesoporous).
One of the key advantages of this technology is that the manufacturing process developed is very inexpensive. Their best results to date (with >95% production yields) have been achieved with fully degradable phosphate-based glasses, which uniquely also provide fully tailored dissolution profiles (which can be controlled from days/months to years). Other glass materials such as borate based glasses have also shown high production yields. Trials are underway with alternate sustainable materials to include silicate based glasses and other glass ceramics.
These highly porous glass microspheres could be utilized in varying applications; so far they have successfully demonstrated that they can remove varying dyes (e.g. acid red, trypan blue) and bacteria from water via simple gravity feed (i.e. they could be utilized in wastewater treatment applications).