| abstract |
The invention relates to a process for the production of (prefabricated) foams and / or fillers based on lignocelluloses such as lignite or peat, and / or carbon powder and, if appropriate, other fillers based on organic, inorganic or metal powder, which are lumpy or sheet-like, the fillers being abrasion-resistant bound containing anionically modified, polyurethane (urea) compositions with a very high water absorption capacity (WAF) of 93-97% and an anionic group content of 10 to 3000 milliequivalents per 1000 g. The preparation is carried out by reacting (optionally anionically modified) NCO prepolymers with a functionality of more than 2.1, with far more than stoichiometric amounts of water, chain extenders optionally having anionic groups and in the presence of comminuted, prefabricated foams and / or other further fillers and optionally in Presence of biomass,n n n The invention further relates to the use of these anionic polyurethane (urea) materials, as carriers for biomass in wastewater treatment or in biological fermentation processes. |