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Hydrogen sulfide is a highly flammable, acutely toxic, and extremely hazardous gas that must be captured and removed from a number of important gaseous and liquid streams. This long-standing challenge of capturing H2S has seen the rise of different materials used in different types of technologies over the years. Some of the well-known examples are alkanolamines used as absorbents and metal oxides used as adsorbents. This work presents an exhaustive review of the latest developments and emerging materials in this field, including ionic liquids, deep eutectic solvents, zeolites, carbon-based materials, metal organic frameworks, polymeric membranes, biological methods, advanced oxidation processes, etc. In addition to a detailed discussion of the state of the art, this review also provides a general technology map and identifies opportunities and challenges to guide future work.

The outbreak of SARS-CoV-2 pandemic highlighted the worldwide lack of surgical masks and personal protective equipment, which represent the main defense available against respiratory diseases as COVID-19. At the time, masks shortage was dramatic in Italy, the first European country seriously hit by the pandemic: aiming to address the emergency and to support the Italian industrial reconversion to the production of surgical masks, a multidisciplinary team of the University of Bologna organized a laboratory to test surgical masks according to European regulations. The group, driven by the expertise of chemical engineers, microbiologists, and occupational physicians, set-up the test lines to perform all the functional tests required. The laboratory started its activity on late March 2020, and as of the end of December of the same year 435 surgical mask prototypes were tested, with only 42 masks compliant to the European standard. From the analysis of the materials used, as well as of the production methods, it was found that a compliant surgical mask is most likely composed of three layers, a central meltblown filtration layer and two external spunbond comfort layers. An increase in the material thickness (grammage), or in the number of layers, does not improve the filtration efficiency, but leads to poor breathability, indicating that filtration depends not only on pure size exclusion, but other mechanisms are taking place (driven by electrostatic charge). The study critically reviewed the European standard procedures, identifying the weak aspects; among the others, the control of aerosol droplet size during the bacterial filtration test results to be crucial, since it can change the classification of a mask when its performance lies near to the limiting values of 95 or 98%.

Permeation tests of CO2/CH4 and H2S/CH4 mixtures in a commercial Perfluorosulfonic acid membrane, Aquivion® E87-12S, were carried out at different temperatures, namely 27, 35 and 50 °C, and at relative humidity (RH) ranging from 20 to 95%. A purposely modified experimental set up was used to allow mixture testing in a fixed volume variable pressure permeometer. The results confirmed the major influence of water content on the gas permeation behavior in PFSA as permeability strongly increased with RH. CO2 and CH4 results confirmed experimental data already available in the open literature, while, for H2S, permeability increased from a value of 17 Barrer measured at 27 °C and 20%RH up to 450 Barrer at the same temperature but at 95%RH. The selectivity with respect to methane also increased with RH, going from 7 to 36 at the same temperature and in the same RH range. The temperature's increase also improved H2S permeability, which reached 512 Barrer at 50 °C and 85%RH, but slightly decreased selectivity towards methane which in the same conditions was limited to 23. A simple model, already used to describe the permeation behavior of other different gases in PFSA, also proved to be able to fit experimental data of H2S with slight changes of the adjustable parameters.

When someone applies for asylum in Italy, he or she is supposed to compose a personal story – referred to literally as his or her ‘memory’ [memoria] – and to present it in front of a commission. There is a coral work on the assembly of someone’s memory: memories are recounted orally, translated, reported, reconstructed and evaluated. This article focuses on the duality of memory production within the asylum procedure, analyzing the work of legal operators in relation to the act of remembering traumatic events. The former is based on the legal procedures for the recognition of international protection, while the latter is deeply related to the asylum seeker who is required to remember, demonstrate and perform memories, especially traumatic ones. On the one hand, memory represents the key to accessing social rights and thereby promotes the practice of citizenship. On the other hand, memory can be part of a victimisation process that reinforces the refugee label.