Rapid industrialization is consuming too much energy, and non-renewable energy resources are currently supplying the world’s majority of energy requirements. As a result, the global energy mix is being pushed towards renewable and sustainable energy sources by the world’s future energy plan and climate change. Thus, hydrogen has been suggested as a potential energy source for sustainable development. Currently, the production of hydrogen from fossil fuels is dominant in the world and its utilization is increasing daily. As discussed in the paper, a large amount of hydrogen is used in rocket engines, oil refining, ammonia production, and many other processes. This paper also analyzes the environmental impacts of hydrogen utilization in various applications such as iron and steel production, rocket engines, ammonia production, and hydrogenation. It is predicted that all of our fossil fuels will run out soon if we continue to consume them at our current pace of consumption. Hydrogen is only ecologically friendly when it is produced from renewable energy. Therefore, a transition towards hydrogen production from renewable energy resources such as solar, geothermal, and wind is necessary. However, many things need to be achieved before we can transition from a fossil-fuel-driven economy to one based on renewable energy.

In this article, the effect of absorption time on the surface chemistry and pore structure of activated carbon (AC) from waste leaves of Quercus alba with the H₃PO₄ chemical activation method. XRD, SEM, EDX, BET, TGA, and FT-IR analyses of prepared AC were used to figure out the properties of the activated carbon. The results demonstrated that the 48 h absorption time of H₃PO₄ contributed to the highest surface area, 943.2 m²/g, among all the prepared activated carbon samples. As the absorption time of the phosphoric acid activating agent was increased, the surface area initially increased and then started to decrease. The further surface chemical characterization of activated carbon was determined by FT-IR spectroscopic method. Life cycle assessment methodology was employed in order to investigate the environmental impacts associated with the laboratory steps for activated carbon (AC) production. The LCA approach was implemented using OpenLCA 1.10.3 software, while ReCiPe Midpoint (H) was used for environmental impact assessment. The results of the LCA study showed that the impact categories related to toxicity were particularly affected by the utilization of electrical energy (≈90%). The power utilized during laboratory procedures was the main cause of environmental impacts, contributing an average of nearly 70% across all impact categories, with the maximum contribution to the impact category of freshwater ecotoxicity potential (≈97%) and the minimum contribution to land use potential (≈10%).

Syngas has been utilized in the production of chemicals and fuels, as well as in the creation of electricity. Feedstock impurities, such as nitrogen, sulfur, chlorine, and ash, in syngas have a negative impact on downstream processes. Fischer–Tropsch synthesis is a process that relies heavily on temperature to increase the production of liquid fuels (FTS). In this study, waste biomass converted into activated carbon and then a carbon-supported iron-based catalyst was prepared. The catalyst at 200 °C and 350 °C was used to investigate the influence of temperature on the subsequent application of syngas to liquid fuels. Potassium (K) was used as a structural promoter in the Fe-C catalyst to boost catalyst activity and structural stability (Fe-C-K). Low temperatures (200 °C) cause 60% and 80% of diesel generation, respectively, without and with potassium promoter. At high temperatures (350 °C), the amount of gasoline produced is 36% without potassium promoter, and 72% with promoter. Iron carbon-supported catalysts with potassium promoter increase gasoline conversion from 36.4% (Fe-C) to 72.5% (Fe-C-K), and diesel conversion from 60.8% (Fe-C) to 80.0% (Fe-C-K). As seen by SEM pictures, iron particles with potassium promoter were found to be equally distributed on the surface of activated carbon.