Determination of pozzolanic activity for using natural zeolite analcime in sustainability additive cement products

Abstract

It is known that the cement industry is responsible for 5-8% of world CO2 emissions and also for intensive energy consumption. For this reason, cement productions need to sustainability studies. Mineral admixtures added to cement as partial replacement material enable to sustainable blended cement productions due to used less amount of cement. Mineral admixtures with pozzolanic property are also preferred in terms of increasing cement performances. This situation corresponds to improved performance of cement and concrete products as well as saving energy, reducing world CO2 emissions. In recent years, the cement industry has been using natural zeolites extensively as pozzolanic materials. Analcime is known as second valuable zeolite mineral after from clinoptilolite in natural zeolite groups The aim of this study is to determinate the pozzolanic properties of analcime and to investigate whether it has potential availability in sustainable blended cement production. The clinoptilolite was used with comparison purpose in this study. Blaine values, densities, chemical composions, pozzolanic activities, mineralogical structures of analcime and clinoptilolite which are subject of study were determined. Accordance with TS 25, which contains pozzolan conformity criterias, 7-days average compressive strength values of lime-pozzolan mixture samples were determined. The datas obtained shown that, the 7-days average compressive strengths of lime-zeolite (pozzolan) blended samples are 9.02 MPa for clinoptilolite and 6.3 MPa for analcime. The total content of Si02 + Al2O3 + Fe2O3 was 77.3% for clinoptilolite and 73.16% for analcime. Accordingly, analcime which is a natural zeolite satisfies to puzolan conformity criterias in TS 25 has the potential to be an alternative to clinoptilolite which is more widely used in cement productions.