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The present investigation involved the treatment of natural clinoptilolite with varying concentrations of NaOH solutions followed by calcination. The samples' composition and structure were characterized and their performance was investigated in the context of hydrogen (H 2) and carbon dioxide (CO 2) adsorption. While a decreasing SiO 2 /Al 2 O 3 ratio was observed in the NaOH-treated samples, the morphological structure obtained from SEM images and the increase in surface area according to BET results exhibited more pronounced alterations, particularly within the 0.5–1 M NaOH concentration range. The alkali treatment resulted in notable peak sharpening, with the most prominent changes observed in the (020), (100), and (101) lattice planes at the same concentration. However, there were no significant alterations in peak intensities. Although H 2 adsorption (4.0192–26.4726 cm3/g) could reach higher values, higher amounts of CO 2 adsorption (5.2308–20.2700 cm3/g) occurred as the concentration of NaOH increased. This phenomenon was attributed to structural modifications in clinoptilolites. • Alkali treated clinoptilolites are high surface area, low Si/Al content, and non-agglomerated. • NaOH concentration change effected the structural and gas adsorptions characteristics. • NaOH concentration is 0.5 M for optimum adsorption and structural properties. • The highest achievable gas adsorption was obtained for H 2 compared to CO 2. [ABSTRACT FROM AUTHOR]

Climate change and environmental problems, increasing global energy demand, and uncertainties in energy supply have brought the production and use of sustainable energy resources to be crucial. Hydrogen, which is an important energy carrier, is being produced and used globally within the perspective of sustainable energy and environmental technologies. Public awareness is an important step toward the spread of hydrogen energy (HE). In the literature, while public awareness studies focus on renewable energy sources, no study that examines public awareness in the field of HE in a way that addresses different perspectives has come across. This pioneering study aims to explore public awareness of HE by analyzing survey data collected from individuals via basic statistical techniques. Findings indicate that individuals' awareness of hydrogen energy mainly varies according to their knowledge level, education level, and age group. The results of the study will provide an important perspective for all stakeholders on hydrogen energy. Especially the policymakers should consider these results to constitute the frameworks of policy without compromising any perspective of public awareness. [ABSTRACT FROM AUTHOR]

Bio-oil obtained by pyrolysis of biomass contains high amounts of oxygenated compounds as a result its physicochemical properties may give rise to certain challenges. Zeolite-based catalysts, such as clinoptilolite, have the ability to convert oxygenated compounds into less oxygenated compounds.10%Ni/Clinoptilolite catalyst was synthesized by modified polyol method as an alternative to known methods instead of common catalysts to improve bio-oil quality. Catalyzed/uncatalyzed pyrolysis of hazelnut husk (HH) was conducted for two distinct retention times (15 s and 25 s) and two catalyst/biomass ratios (1:1 and 2:1) to determine the effect of the catalyst. The optimal catalyst/biomass ratio for obtaining the highest aromatic hydrocarbon content was found to be two, whereas the highest aliphatic hydrocarbon content was observed at a ratio of one. An increase in retention time from 15 s to 25 s was found to have a positive impact on the composition of bio-oil, whereas it decreased the aromatic hydrocarbon content only when the ratio of catalyst to biomass was two. [ABSTRACT FROM AUTHOR]