# Carbon Dioxide Uptake by Brazilian Cement-Based Materials
## 1 Introduction
### General Background on the Carbonation as a Stage in the Decarbonization Roadmaps  
[PERSON] and [PERSON] [7] performed a life cycle assessment (LCA) based on Ecuadorian inventories to assess the environmental sustainability of the cement industry in Ecuador. They concluded that it could be applied to the broader Latin American region. Global Warming Potential (GWP) for clinker was 897 kg CO\({}_{2}\)/ton and 126-442 kg CO\({}_{2}\)/m\({}^{3}\) for ready-mixed concrete. Nevertheless, they do not yet consider the concrete carbonation process in their life cycle assessment (LCA). [PERSON] [8] presented the decarbonization roadmaps for the ten ASEAN countries for the first time. Countries belonging to the Association of Southeast Asian Nations (ASEAN) are Brunei Darussalam, Burma, Cambodia, Indonesia, Laos, Malaysia, Philippines, Singapore, Thailand, and Vietnam. The ASEAN countries are rich in natural resources containing up to 20% of all known species of the world. The equator passes through both the north of Brazil and Indonesia. Thus, some climatic similarities between some regions of Brazil and the ASEAN countries can be found. However, the ASEAN area is facing a substantial increase in temperature and rainfall intensity and duration, with frequent floods, droughts, and fires. [PERSON] [8] highlighted that to decarbonize industries which require high-temperature heating such as the cement sector, hydrogen can be used. In addition, considering carbon capture and storage in the roadmap, it was mentioned in particular that there are 57 Gt of CO2 storage potential in Vietnam, Thailand, Philippines, and South Sumatra. Nevertheless, the roadmap has, unfortunately, not considered the cement-based materials' carbonation yet. The technical and economic systems that serve to minimize waste and maximize the reuse of resources, material efficiency measures, biofuel substitution, renewable electricity usage, and carbon capture and storage are known as \"the new circular economy paradigm\". Recent studies based on this paradigm have demonstrated that carbon dioxide emissions associated with Building Design + Construction and transport infrastructures can be lowered about 50% by 2030 and 90% by 2045 [9]. However, while concrete structures can uptake part of the embodied carbon dioxide if exposed to air, this is not considered in some recent studies [10]. By contrast, the same authors included concrete carbonation in the reference LCA study. A limited number of reviews have been performed to shed light on the capacity of concrete for natural carbonation, carbonation curing, and mineral carbonation, which are either focused on one of these carbonation procedures or oriented to assess the impact of carbonation on the mechanical and durable properties of the concretes [11]. Accelerated carbonation as an effective approach for reducing the carbon footprint in cement-based materials has been widely researched. With regard to the selection of carbon dioxide utilization products, three criteria are assessed for each product: technology readiness level (TRL), carbon dioxide uptake potential, and energy demand. The technology readiness level (TRL) definitions of the different technological routes were provided in the Horizon 2020 Work Programme [12]. Carbonated concrete and aggregates production via carbon dioxide mineralization is at TRL 9 \"actual system proven in operational environment\". Some examples are Solidia Cement(tm) and CarbonCure(tm) to produce carbonated cement by carbon dioxide curing technology and Carbon8 for carbonated aggregates [13]. [PERSON] et al. [14] studied accelerated carbonation on recycled concrete aggregates (RCAs) and recorded a mean value of CO2 uptake of about 15-20 g/kg RCA. In addition, accelerated carbonation reduced by 67% the water absorption coefficient, decreasing the total porosity as a result of the capillary pores clogging. By contrast, RCA microprosity is increased as a result of the C-S-H gel decalcification.