# Performance of Molasses Waste as a Cement Replacement to Study Concrete Compressive Strength
## 1 Introduction
The energy-intensive production of cement results in significant carbon dioxide emissions. Various studies have shown that the production of cement for the manufacture of concrete releases approximately 0.8 tons of carbon dioxide into the air per ton of cement and that Portland cement releases approximately one ton of carbon dioxide into the atmosphere [30]. It has also been estimated that the cement industry is responsible for 8% of global CO\({}_{2}\) emissions [31]. The two main factors responsible for this result are:  
1. The use of fossil fuels to generate the temperature required to form the main component of cement, clinker. 2. The calcination of limestone, which results in the release of CO\({}_{2}\). Indeed, as previously mentioned, significant environmental effects are caused by the production of cement for the manufacture of concrete, including substantial energy consumption and greenhouse gas emissions that contribute to global warming [32]. To address these issues, researchers and engineers have been looking for alternative materials that can partially or entirely replace cement in concrete without affecting its performance and durability [33]. Molasses waste, a by-product of the sugar industry, is one such material. It is obtained during the sugar crystallization process. The juice, after being extracted from the sugar cane, is boiled until the sugar crystallizes and precipitates. The liquid obtained after sugar crystallization is called molasses [34; 35]. It has the following characteristics:  
1. It is a dense and viscous liquid. 2. It is dark brown. 3. It contains a lot of sugar and a small amount of water, although no more sugar can be obtained by further crystallization. 4. Its density varies from 1.4 to 1.5 g/mL. In general, it is estimated that 100 tons of sugarcane will produce about 4 tons of molasses, most of which is used domestically, while only 7% of the world's production goes to the international market [29]. Molasses waste is sometimes discarded as a waste product, causing disposal and environmental problems [36]. However, it has several properties that could make it a contender to replace cement for the production of concrete. Therefore, instead of discarding this by-product as waste, it can be employed as a useful ingredient in the production of concrete, which could revolutionize the entire construction industry. Its function as a cement substitute could reduce the side effects caused by the large-scale production of cement, i.e., the abundant use of non-renewable resources and the immense emission of carbon dioxide leading to global warming and climate change. Moreover, the waste management and environmental problems caused by its improper disposal can be decisively minimized if it becomes a good substitute for cement in the production of concrete. Improving the measures leading to a carbon-free urban environment, especially in the construction sector, is one of the growing obligations of the developed society [37; 38]. A review of the literature revealed that a large number of investigations have been conducted on this topic. [PERSON] [39] examined the use of molasses as a time-delaying additive in concrete. In this study, the setting times of molasses-based concrete were tested at three different dosages of 0.40%, 0.60%, and 0.80% wt. of cement content. It was shown that both the initial and final setting times were significantly prolonged by the addition of molasses. The strength increased significantly; there was no negative impact on its other performance parameters like workability. The study by [PERSON] [40] compared natural concrete with concrete made by adding molasses and steel slag at a constant water-to-cement ratio and adding 25%, 50%, 75%, 80%, and 90% slag and 0.3, 0.6, 0.9, 1.2, and 1.5% of molasses, respectively. These tests showed that adding up to 0.90% molasses and 75% steel slag increased the compressive strength of the concrete.