The Effect of Natural Zeolite on Stucco and Mortar Production
A significant amount of carbon dioxide emissions are generated during the production of Portland cement. To locate environmentally friendly alternatives, the scientific community has examined how natural zeolites might serve as a supplementary material in cement mixes. For example, Najimi et al. (2012) tested the mechanical and durability properties of concrete made with 15 percent and 30 percent of natural zeolite, and tested them against mixes without natural zeolite. The results demonstrated that zeolite concrete mixes were effective in regards to water and chloride penetration, corrosion rates, and drying/shrinkage of concrete. Overall, it was found that the incorporation of 15 percent natural zeolite is an appropriate option to improve strength and durability properties of concrete (Najimi, 2012).
To study the properties and behavior of cement mortar with clinoptilolite, Bilim (2011) prepared six mortar mixtures that replaced Portland cement with 0%, 5%, 10%, 15%, 20%, and 30% zeolite by weight. The results indicated that the strength values (compressive and flexural strength) of the mortars containing clinoptilolite were higher that the control mixture (Bilim, 2011). The researcher also observed a decrease in water absorption and porosity of mortars containing zeolite. Also, the freeze-thaw resistance of the mortars containing 5 percent clinoptilolite was higher than the control mortar. Bilim concluded that clinoptilolite incorporated mortars show durability and can lead to considerable economic benefits (Bilim, 2011).
Janotka and Mojumdar (2003) conducted a study to characterize sulphate resistance of mortars made from Portland cement and Portland – pozzolan cement with 35 wt% of zeolite addition-zeolite based cement (ZBC). The two types of mortars were tested in water and a 5 percent sodium sulphate solution for 720 days. Results indicated that the sulphate resistance of zeolite is markedly higher than that of Portland cement (Janotka & Mojumdar, 2003).