Comprehensive Analysis of Geopolymer Materials: Properties, Environmental Impacts, and Applications

Abstract

The advancement of eco-friendly technology in the construction sector has been improving rapidly in the last few years. As a result, multiple building materials were developed, enhanced, and proposed as replacements for some traditional materials. One notable example presents geopolymer as a substitute for ordinary Portland concrete (OPC). The manufacturing process of (OPC) generates CO2 emissions and a high energy demand, both of which contribute to ozone depletion and global warming. The implementation of geopolymer concrete (GPC) technology in the construction sector provides a path to more sustainable growth and a cleaner environment. This is due to geopolymer concrete’s ability to reduce environmental pollutants and reduce the construction industry’s carbon footprint. This is achieved through its unique composition, which typically involves industrial byproducts like fly ash or slag. These materials, rich in silicon and aluminum, react with alkaline solutions to form a binding gel, bypassing the need for the high-energy clinker production required in OPC. The use of such byproducts not only reduces CO2 emissions but also contributes to waste minimization. Additionally, geopolymer offers extra advantages compared to OPC, including improved mechanical strength, enhanced durability, and good stability in acidic and alkaline settings. Such properties make GPC particularly suitable for a range of construction environments, from industrial applications to infrastructure projects exposed to harsh conditions. This paper comprehensively reviews the different characteristics of geopolymers, which include their composition, compressive strength, durability, and curing methods. Furthermore, the environmental impacts related to the manufacturing of geopolymer materials were evaluated through the life-cycle assessment method. The result demonstrated that geopolymer concrete maintains positive environmental impacts due to the fact that it produces fewer carbon dioxide CO2 emissions compared to OPC concrete during its manufacturing; however, geopolymer concrete had some minor negative environmental impacts, including abiotic depletion, human toxicity, freshwater ecotoxicity, terrestrial ecotoxicity, and acidification. These are important considerations for ongoing research aimed at further improving the sustainability of geopolymer concrete. Moreover, it was determined that silicate content, curing temperature, and the proportion of alkaline solution to binder are the major factors significantly influencing the compressive strength of geopolymer concrete. The advancement of geopolymer technology represents not just a stride toward more sustainable construction practices but also paves the way for innovative approaches in the field of building materials.

Evaluating Techno-Eco-Efficiency of Waste Clay Brick Powder (WCBP) in Geopolymer Binders

“…The CV ranges from 0.82% to 1.85% for the primary impact "Human toxicity", suggesting that there is relatively low uncertainty in the calculated values for these impacts. The results of this study are comparable with other studies, as Miyan et al [29] found that recycled waste concrete consistently reduced carbon emissions, cumulative energy demand, and costs, where alkaline solutions are a hotspot accounting for a significant portion of the impacts [29,35,50]. Therefore, Munir et al [51] obtained industrial-based geopolymer concrete with an improved environmental performance using lower quantities of sodium silicate.…”

“…However, this shift may lead to a significant increase in other environmental impacts due to the use of alkaline activators or grinding. Sbahieh et al [50] confirmed that the geopolymer concrete has lower carbon emissions compared to OPC concrete during manufacturing, yet it presents minor adverse environmental effects, including abiotic depletion, human toxicity, freshwater ecotoxicity, terrestrial ecotoxicity, and acidification.…”

Synthesis of Electrolytic Manganese Slag–Solid Waste-Based Geopolymers: Compressive Strength and Mn Immobilization

“…The harmless treatment of electrolytic manganese slag mainly includes water washing [ 4 ], acid leaching [ 5 ], electrokinetic restoration [ 6 ], solidification/stabilization (solidification/stabilization, S/S) technology [ 7 ], and other routes. The first three methods have high processing costs and complex technical routes, with scholars now favoring efficient, energy-saving, easy-to-operate S/S technology; compared with other S/S technologies, geopolymers have the advantages of fast setting and early strengthening, good durability, inexpensive costs, and low carbon emissions, which have attracted the attention of researchers [ 8 , 9 , 10 ].…”

Factors affecting durability properties of GPC: A review

“…In addition to its superior strength and durability, GPC offers a myriad of advantages, establishing itself as a compelling choice for contemporary construction practices [4]. Notably, GPC exhibits exceptional early-age strength and benefits from ambient curing conditions, contributing to accelerated construction timelines [5]. The intricacies of GPC's durability and strength hinge on various factors, including the selection of binders, the alkali-activating solution employed, and the nuances of the curing process [6].…”

“…Geopolymers have emerged as a focal point in contemporary research and development, holding substantial promise as ecologically beneficial and sustainable alternatives to traditional cement-based materials [5]. The impetus behind geopolymer research lies in its potential to significantly alleviate the environmental impact associated with conventional Portland cement production [20].…”