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Hydrogen is becoming an attractive alternative for energy storage and transportation, because of the elevated energy content per unit of mass and possibility to have zero carbon-emission vehicles. For these reasons, hydrogen's share in global market is expected to grow substantially in the coming years. Today, hydrogen-fueled buses and cars are already available, and several refueling stations are operating in different countries around the world. A key role of the deployment of hydrogen fueled-vehicles is the presence of a widespread network of refueling stations, especially close to residential and industrial areas. This fact poses attention to the safety aspects related to hydrogen, with particular interest to its high flammability that can lead to catastrophic consequences for personnel and equipment. As a matter of fact, hydrogen is a comparatively less hazardous fuel compared to conventional fuels such as gasoline and diesel. Hydrogen infrastructures are characterized by operating pressure up to 1000 bar that, in case of an unintended loss of containments, may produce a highly under expanded turbulent jet. If ignited, this hydrogen jet may give rise to very severe scenarios, mainly related to high temperatures and the oriented flows. As recently suggested by Moradi and Groth (Moradi and Groth, 2019), there is a lack of experimental and on-site data for almost all of the storage and delivery technologies relevant to the hydrogen infrastructures. Experimental data is vital to support model validation, especially in the case of the very peculiar combustion process of hydrogen. In this way, a real-scale experimental campaign is proposed to investigate the main characteristic of the hydrogen jet fire resulting from its rapid fired depressurizations. The focus of the experimental campaign is the evaluation of safety distance for person and device (i.e. pressurized tanks) in order to avoid critical conditions and domino effects in refueling station. Different initial conditions, i.e., storage pressures, are exploited, and the resulting jet across specified orifice are investigated. More specifically, temperatures at various locations are measured through an arrangement of thermocouples. Values up to 1200 °C were obtained in the core of the jet. Moreover, it was found that the recorded temperatures, especially those at the outer portion of the jet, are very sensitive to the initial conditions.

Epoxidized vegetable oils are largely employed as plasticizers instead of harmful phthalates, and they can be a sustainable choice to produce lubricants and intermediates. The aim of this work is to study the reaction of soybean oil epoxidation of soybean using safer reactants. The reaction was carried out using hydrogen peroxide 34 wt % and acetic acid instead of the commonly used hydrogen peroxide at 60 wt % and formic acid to reduce the risk of detonation and corrosion. Moreover, the study focuses on the efficacy of the presence of an acid catalyst and sulfuric acid and the effect of its concentration. It was found that it is not possible to carry out the process without acid catalyst with those reactants. In addition, a proper mixing program was set up to improve the selectivity of the reaction. © 2018 American Chemical Society.