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Alternative Fuel for Transportation
Published in Atul Sharma, Amritanshu Shukla, Renu Singh, Low Carbon Energy Supply Technologies and Systems, 2020
Sumit Lonkar, Prashant Baredar
After the reforming reaction, the gas is rapidly cooled down to about 350°C–450°C before it enters the water–gas shift reaction. This reaction is exothermic, and heat is released during the reaction. Here, shifting of an oxygen atom from water to CO takes place and forms CO2, which can be separated and stored. () CO+H2O↔CO2+H2Δh=−42kJ/Mole
Environmental impacts and mitigation
Published in Lucy Budd, Stephen Ison, Air Transport Management, 2020
In order to create sufficient thrust and lift to overcome the effects of aircraft weight and aerodynamic drag, aircraft engines burn kerosene – an energy-rich fossil fuel. Modern high-bypass jet engines work by sucking in large volumes of air through the front fan. A high proportion of this cold air bypasses the central engine core and is mixed with hot exhaust gases at the rear to create additional thrust. The remaining air enters the central compressors and combustion chamber where fuel is injected and ignited. The resulting exothermic reaction produces a range of gaseous and solid pollutants – including carbon dioxide (CO2), nitrous oxides (NOx), water vapour (H2O), and particulate matter (PM) – which change the chemical composition of the atmosphere and generate different effects depending on the location and altitude at which they are released. Aircraft also generate noise pollution from the engines and airframe. Aircraft-derived atmospheric and noise pollution are inherently mobile, whereas aviation’s other environmental impacts occur at fixed locations at and around airports.
Energy, Environment, and Renewable Energy
Published in Radian Belu, Fundamentals and Source Characteristics of Renewable Energy Systems, 2019
Chemical energy is the one associated with chemical bonds, the energy interaction between atomic electrons in a material. It can be absorbed or released during chemical reactions, due to the changes in the bonds between the atoms. Processes requiring energy input for the reaction are known as endothermic, while the ones releasing energy during the reaction are known as exothermic. The last ones are of interests in energy generation. Among the exothermic processes of great interest are the ones involving the oxidation of carbon, such as pure carbon oxidation, producing of carbon dioxide and releasing the (thermal) energy. () C+O2→CO2+32.8 MJ/kg
Correlating solvation-adsorption phenomena of some styrylpyridinium dyes on SDS modified silica surface in organic media
Published in Journal of Dispersion Science and Technology, 2022
Raisarani Sharma, Pravin Kumar Kar, Sukalyan Dash
Thermodynamic parameters for the adsorption of the dye molecules have been calculated using Van’t Hoff equation (Equations (3)–(5)) (Supplementary Figure S8). The entropy change (ΔS) for each dye is having a negative value which can be attributed to the decrease in randomness of the dye molecules due to the aggregation over the silica surfaces at solid-liquid interface. Negative enthalpy change (ΔH) ensures the process to be exothermic in nature. Positive values of free energy change (ΔG) and its increment with temperature may be due to a decrease in the attractive forces between the adsorbate molecules and adsorbent surfaces.[36] The anchoring of dye molecules on SDSMS is an enthalpy-controlled process as the values of ΔH is higher than TΔS (Supplementary Table S1).[37]
Impact of exothermic chemical reaction on MHD unsteady mixed convective flow in a rectangular porous cavity filled with nanofluid
Published in Waves in Random and Complex Media, 2022
Figure 10 represents the isotherms for rising values of the Frank–Kamenetskii number. It is well known that the exothermic chemical reaction processes generate more heat. Therefore, the exothermic chemical reactions lead to enhance the energy transfer. As a result, increasing values of the Kamenetskii number produce more heat to the fluid. The application of the exothermic chemical reaction process occurs in various industrial situations including packed bed reactors, chemical vapor deposition systems, tubular laboratory reactors, oxidation of solid materials in large containers, energy recovery, and thermal storage. In the present analysis, the energy transmission is higher at the middle of the enclosure and it is lower near the vertical walls. For Fk = 0.1, the magnitude of the interior isotherms is 0.32156. For Fk = 1, it is raised to 0.48203, and for Fk = 3, the value becomes 1.113. It is observed that the highest value () of the Frank–Kamenetskii number is associated with the strongest (1.113) energy transmission inside the cavity.
Improvements in mechanical and durability parameters of bio-engineered concrete with metakaolin as a partial substitute for cement
Published in European Journal of Environmental and Civil Engineering, 2022
Vighnesh Rameshkumar, S. Prabhath Ranjan Kumar, V. Poornima, R. Venkatasubramani, V. Sreevidya
Concrete is probably the most common entity used in the construction industry because of its many advantages. The concrete gains strength through the various reactions of cement and water (hydration process). However, these reactions are exothermic and release a lot of heat adding to the GHG (Green House Gases) (Anto Edison James et al., 2015). In addition, the curing process leads to various micro cracking on the concrete surface. Although, these cracks are tiny, these provide a path for fluids to enter the core of concrete reducing the pH of concrete from alkaline to acid, which disrupts the functionality of concrete and its underlying reinforcement (Shetty, 1982). In order to evade such complications, the idea of bio-engineered concrete was proposed. Bacterial medium was included in the mixing process of concrete. This concrete is capable of producing calcite and closes the tiny pores, thereby increasing the durability