KALSİT İLAVELİ JEOPOLİMER MALZEMELERİ SİNTERLEMENİN GÖZENEKLİLİĞE ETKİLERİ - SINTERING OF CALCITE ADDED GEOPOLYMERIC MATERIALS EFFECTS ON POROSITY

KALSIT ILAVELI JEOPOLIMER MALZEMELERI SINTERLEMENIN GOZENEKLILIĞE ETKILERI Bu calismada, ucucu kul esasli jeopolimerlere kalsit ilavesiyle elde edilen malzemelerin farkli sicakliklarda sinterlenmesi ile gozeneklilige etkileri arastirilmistir. Bu amacla, ucucu kul (100U) ve %20 kalsit ilaveli ucucu kul(80U20K) ile jeopolimerik kompozisyonlar hazirlanmistir. Bu kompozisyonlarin sodyum hidroksit (12M), sodyum silikat cozeltileriyle aktive edilmesi ve daha sonra numunelerin 80°C’de 24 saat kurlenmesi ile jeopolimerik yapilar elde edilmistir. Elde edilen jeopolimerik numuneler, 500, 700 ve 900°C’de 30 dakika sureyle sinterlenmistir. Jeopolimer malzemelerde kalsitin sinterleme davranislarina etkisi termal analiz (DSC) ile belirlenmistir. Uretilen malzemeler faz analizi (XRD), gozenek boyutu (civa porozimetre), gorunur yogunluk, acik gozeneklilik ve su emme analizleri ile karakterize edilmistir. Sinterleme sicakliginin artmasi ile malzemelerde acik gozeneklilik degerlerinde azalma meydana gelmistir. Jeopolimer malzemelerin 900°C’de sinterlenmesi ile nefelin gibi camsi fazlarin olusumu, 100U numunesinde acik gozeneklilik degerini %29,78’den %12,30’a dusururken, 80U20K numunesinde ise %39,23’den % 32,65’e dusus SINTERING OF CALCITE ADDED GEOPOLYMERIC MATERIALS EFFECTS ON POROSITY In this study, the effects of sintering at different temperatures on porosity of materials produced by addition of calcite in fly ash based geopolymers are investigated. For this purpose, geopolymeric compositions are prepared by fly ash (100U) and 20% calcite added fly ash (80U20K). Activating of these compositions with sodium hydroxide(12M) and sodium silicate solutions and then curing of the samples at 80 °C for 24 hours geopolymeric structures are obtained. The produced geopolymeric samples are sintered at 500°C, 700°C, and 900°C temperatures for 30 minutes. The temperature increase rate is 5°C/min. The effects of calcite in geopolymeric materials on sintering behaviour are determined by thermal analysis (DSC). The produced materials are characterized by phase analysis (XRD), porous size (mercury porosimeter), apparent density, open porosity, and water absorption analysis. As the sintering temperature is increased, open porosity values in materials decrease. Emergence of glassy phases such as nepheline by sintering the geopolymeric materials at 900°C, decrease 100U sample open porosity value from %29.78 to 12.30%, 80U20K sample value from %39.23 to 32.65%. Calcite addition to the materials provides porosity in the samples at 900°C, the temperature at which glassy phases emerge.