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Carbon capture and sequestration (CCS) has been employed to reduce global warming, which is one of the critical environmental issues gained the attention of scientific and industrial communities worldwide. Once implemented successfully, CCS can store at least 5 billion tons of CO2 per year as an effective and technologically safe method. However, there have been a few issues raised in recent years, indicating the potential leakages paths created during and after injection. One of the major issues might be the chemical interaction of supercritical CO2 with the cement, which may lead to the partial or total loss of the cement sheath. There have been many approaches presented to improve the physical and mechanical properties of the cement against CO2 attack such as changing the water-to-cement ratio, employing pozzolanic materials, and considering non-Portland cements. However, a limited success has been reported to the application of these approaches once implemented in a real-field condition. To date, only a few studies reported the application of nanoparticles as sophisticated additives which can reinforce oil well cements. This paper provides a review on the possible application of nanomaterials in the cement industry where physical and mechanical characteristics of the cement can be modified to have a better resistance against corrosive environments such as CO2 storage sites. The results obtained indicated that adding 0.5 wt% of Carbon NanoTubes (CNTs) and NanoGlass Flakes (NGFs) can reinforce the thermal stability and coating characteristics of the cement which are required to increase the chance of survival in a CO2 sequestrated site. Nanosilica can also be a good choice and added to the cement by as much as 3.0 wt% to improve pozzolanic reactivity and thermal stability as per the reports of recent studies. [ABSTRACT FROM AUTHOR]

Cement is considered a key raw material for brick production. However, excessive use of cement leads to a negative environment impact. Cement replaced with locally available waste materials has a significant potential to address this environmental impact, especially in the construction industry by contributing to cleaner production. The objective of this research is to investigate the performance of brick where cement is replaced by fly ash and palm oil fuel ash, waste materials typically available in Malaysia, where the construction industry is on the rise. To determine the performance of these bricks, a compressive strength test, a water absorption test, and a thermogravimetric analysis were carried out at different percentage combinations of fly ash and palm oil fuel ash. The results from the tests reveal that both fly ash and palm oil fuel ash incorporated bricks satisfy Class 1 and Class 2 load-bearing brick requirements according to the Malaysian Standard MS76:1972 along with water absorption requirements as per ASTM C55-11. The thermogravimetric analysis study confirms that the Ca(OH)2 gradually decreases due to the increase of pozzolanic material contents (fly ash and palm oil fuel ash). Moreover, these newly developed bricks cost less than the conventional bricks. [ABSTRACT FROM AUTHOR]