Title |
The influence of zeolitic by-product containing ammonium ions on properties of hardened cement paste / |
Authors |
Vaičiukynienė, Danutė ; Mikelionienė, Agnė ; Kantautas, Aras ; Radzevičius, Algirdas ; Bajare, Diana |
DOI |
10.3390/min11020123 |
Full Text |
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Is Part of |
Minerals.. Basel : MDPI. 2021, vol. 11, iss. 2, art. no. 123, p. 1-11.. ISSN 2075-163X |
Keywords [eng] |
fluid catalytic cracking (FCC) catalysts ; zeolitic by-product ; Portland cement hydration |
Abstract [eng] |
Fluid catalytic cracking (FCC) catalysts, used in the petroleum industry, are sources of zeolitic by-products. These by-products are often used as sorbents for the removal of ammonium ions from wastewater. After a period of use, the zeolitic by-product loses its sorption properties and is no longer effective. The problem is the use of zeolitic by-product with ammonium ions. In this study, a zeolitic by-product containing ammonium ions and high contents of active SiO2 and Al2O3 was used as a supplementary cementitious material (SCM). Cement pastes containing 0.5%, 1%, 3%, 5%, and 10% of the by-product were prepared, and the compressive strength and density of the pastes were evaluated. Incorporation of the zeolitic by-product increased the cement strength by 17% and 32% after 7 and 28 days of hydration, respectively. Thus, incorporation of the zeolitic by-product with ammonium ions as an SCM has a complex effect on an ordinary Portland cement (OPC) system. Ammonium chloride accelerated cement setting after 7 days of hydration, and the pozzolanic reaction positively affected strength development after 28 days of hydration. The reaction products caused the cement to have a compact microstructure. The zeolitic by-product containing absorbed ammonium ions can be successfully reused to replace ordinary Portland cement in cement pastes. |
Published |
Basel : MDPI |
Type |
Journal article |
Language |
English |
Publication date |
2021 |
CC license |
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