Na2O–CaO–SO3 Ceramics As Promising Inorganic Porogens

Ceramics with post-firing (600 – 900°C) phase composition represented by calcium sulfate anhydrite CaSO 4 and sodium calcium sulfates (Na 0.8 Ca 0.1 ) 2 SO 4 and Na 6 Ca(SO 4 ) 4 was obtained from a powder mixture of sodium sulfate Na 2 SO 4 and calcium sulfate dihydrate CaSO 4 ∙ 2H 2 O with molar ratio CaSO 4 ∙ 2H 2 O/Na 2 SO 4 = 1. The phase composition of the powder mixture after homogenization (in acetone) in a planetary mill included, in addition to the initial salts, hydrated sodium calcium sulfate Na 4 Ca(SO 4 ) 3 ∙ 2H 2 O. On soaking in water for 5 and 60 min the weight loss of the ceramic sample fired at 700°C was equal to 15 and 75%, respectively. Na 2 O–CaO–SO 3 ceramics in the form of granules or complex structures obtained by means of 3D printing can be used as a removable (soluble or leachable) porogen and (or) a prototype of a porous space with specified architecture to obtain porous polymeric or inorganic materials.