The forthcoming ordinance on the handling of sewage sludge in Germany will contain a paragraph on the recovery of phosphorus. Hence, the subject of phosphorus recycling attains increasing attention in policy, municipality and industry. Calcium silicate hydrates (CSH) are made from quartz, lime and water under elevated temperature and pressure conditions. Great specific surfaces and surface charges make CSH-phases a promising reaction material for phosphorus. Here the possibilities for a CSH synthesis in terms of optimized recovery capabilities and the use of noncritical and inexpensive raw materials.