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Though food scarcity realizing in many places in the world, food waste generation still shows its increasing trend because of cultural and habitual changes, as well as technological characteristics. However, food waste comprises a large amount of organic material and biodegradable components, showing that it could be a potential source for producing hydrogen (H 2) aiming to satisfy the key goals of diversifying the energy supply and reducing environmental pollution. Indeed, this research addresses the potential possibilities to use food waste for the production of H 2 by using a water gasification reactor. In this work, food waste was gasified by varying the operating parameters in the H 2 production process and the addition of additives. In this investigation, different additives such as HCl, NaCl, and NaHCO 3 were considered to investigate at different reactor temperatures like 300, 350, and 400 °C for different reaction durations like 30, 45, and 60 min. The results revealed that the best average yields of CH 4 , H 2 , CO 2 , CO, and total gas were obtained as 1.5, 12.9, 0.2, 0.1, and 13.9 mol/kg, respectively, when the reaction employed with NaHCO 3 additive than the other cases (with HCl, NaCl additives and no additive cases). The H 2 production efficiency was estimated as 43%, 34%, 27%, and 30% when the use of NaHCO 3 , NaCl, HCl, and no additives. Hence, it is found that the NaHCO 3 catalyst considerably enhances the gasification process through the improvement of the water-gas shift reaction, and thereby H 2 production increases. [Display omitted] • Hydrogen Production from food waste possibilities were experimentally analyzed. • HCl, NaCl, and NaHCO 3 Alkaline metals additives tested in H 2 production. • Analyzed influence of reaction temperature and reaction duration in H 2 production. • NaHCO 3 additive with food waste, improves the water-gas shifting reaction. • NaHCO 3 additive recorded 12.9 mol/kg H 2 production & production efficiency 43%. [ABSTRACT FROM AUTHOR]

Environmental effects of heavy metal pollution are considered as a widespread problem throughout the world, as it jeopardizes human health and also reduces the sustainability of a cleaner environment. Removal of such noxious pollutants from wastewater is pivotal because it provides a propitious solution for a cleaner environment and water scarcity. Adsorption treatment plays a significant role in water remediation due to its potent treatment and low cost of adsorbents. In the last two decades, researchers have been highly focused on the modification of adsorption treatment by functionalized and surface-modified nanomaterials which has spurred intense research. The characteristics of nano adsorbents attract global scientists as it is also economically viable. This review shines its light on the functionalized nanomaterials application for heavy metals removal from wastewater and also highlights the importance of regeneration of nanomaterials in the view of visualizing the economic aspects along with a cleaner environment. The review also focused on the proper disposal of nanomaterials with crucial issues that persist in the adsorption process and also emphasize future research modification at a large-scale application in industries. [Display omitted] • Role of nanotechnology in heavy metal removal is reviewed. • Preparation and functionalization of nanomaterials are discussed. • Potential of carbon-based nanomaterials in wastewater remediation is visualized. • Various factors affecting the adsorption of heavy metals are discussed. • Regeneration potential of nano-adsorbents is examined. [ABSTRACT FROM AUTHOR]

To meet demands in agricultural sectors, the way of waste-to-useful products is an alternative to conventional processes capable of generating on-site products. This is an innovative method leading to designing a novel combined system in the current work. By means of a precise chemical and electrochemical simulation, the rice husk (an agricultural biomass fuel) is processed through a gasifier with a steam agent and is utilized in a molten carbonate fuel cell. The fuel cell's waste heat is delivered to thermal-based desalination utilizing humification and dehumidification processes. In addition, a solid oxide electrolyzer cell creates hydrogen by consuming power supplied by the fuel cell. Consequently, the system is able to meet some demands like electricity, irrigation, and chemical fertilizers. Accordingly, the system's applicability is measured by comprehensive electrochemical, technical, and environmental sensitivity analyses along with an advanced triple-objective optimization using the method of artificial neural network (ANN) + multi-objective grey wolf optimization. Regarding the objective functions, i.e., exergetic efficiency ( E x E t o t ), exergoenvironmental impact index ( E I I t o t ), and carbon dioxide emission ( C D E t o t ), the optimum state brings E x E t o t = 29.98 % , E I I t o t = 2.28 , and C D E t o t = 391.1 k g / M W h. Also, the variability of studied variables is further affected by the fuel cell's current density; its mean sensitivity index equals 0.48. [Display omitted] [ABSTRACT FROM AUTHOR]

Integrating nanotechnology into phase change materials (PCMs) has emerged as a novel approach to improving PCM thermal properties and performance in various thermal energy storage applications. Nanofluids, nanoparticle suspensions in a base fluid, have been identified as a promising method of increasing the thermal conductivity of PCMs and thus reducing thermal energy charging and discharging duration. This review paper investigates recent advances in incorporating nanotechnology into PCMs, focusing on their applications in the solar energy sector. Thermal conductivity, specific heat, viscosity, density, and convective heat transfer coefficient of nanofluids are discussed, as are the thermal properties of nano-enhanced PCMs (NEPCMs), including thermal conductivity, latent heat, specific heat, viscosity, supercooling, and phase-change temperature. The paper also gives an in-depth look at the uses of nanofluids and NEPCMs in solar collectors, photovoltaic/thermal (PV/T) systems, coolants, and desalination, emphasizing their potential to improve system efficiency. The review also considers the potential environmental and human health concerns connected with using nanofluids and NEPCMs, emphasizing the importance of rigorous evaluation and risk assessment in developing and applying these materials. Overall, the review provides valuable insights into the potential benefits and challenges of incorporating nanotechnology into PCMs and emphasizes the importance of ongoing research and development in this field to further advance the use of thermal energy storage technologies in various applications, including solar energy systems. [Display omitted] • Nanofluids and nanomaterials are considered as innovative heat transfer medium. • Phase change materials (PCMs) for harvesting thermal energy are scrutinized. • Recent developments and properties of nanofluids and nano-enhanced PCM. • Potential applications of nanofluids and nano-enhanced PCM are fully presented. • Environmental impacts and human health risks are comprehensively discussed. [ABSTRACT FROM AUTHOR]