Alginate is currently extracted from seaweed. It is used to a limited extent in the medical world (denture mould, alginate plasters and cough medicine). By cleverly combining existing and new techniques, the raw material Kaumera Nereda® Gum, which shows similarities with alginate, can be extracted from sludge granules that form during the Nereda® purification process.
Prof. dr. ir. Mark van Loosdrecht of TU Delft is the developer of this purification process. Yuemei Lin, assistant professor at Van Loosdrecht's group, discovered that the polymer in Nereda® sludge granules is mainly alginate. She is now exploring this further with PhD student Simon Felz (TU Delft). Prof. Stephen Picken and PhD student Jure Zlopasa are doing research into all kinds of applications of the alginate-like polymer in the field of materials. TU Delft, for example, has developed a concrete coating.
To protect concrete, polyester or another material from the oil industry is currently often used. This must be applied several times and is not degradable. The TU Delft coating is a natural product consisting of alginate, a substance extracted from algae, combined with tiny clay particles. The material is completely biodegradable and only needs to be applied once. The alginate coating reacts chemically with calcium in the concrete, immediately creating a waterproof layer.