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In this experimental work, the ethanol steam reforming reaction for producing hydrogen was studied in both a traditional reactor (TR) and a Pd-Ag dense membrane reactor (MR). Both reactors have been packed with a commercial Ru-based catalyst. The experimental tests have been performed in the temperature range 400-500 °C and in the pressure range 2.0-3.6 bar.The results are reported in terms of ethanol conversion, hydrogen production, product selectivities and hydrogen recovery (for the MR only). It has been found that the MR is able to increase the ethanol conversion as well as increase the hydrogen production with respect to a traditional reactor. Moreover, part of the hydrogen produced in the MR is recovered as a CO-free hydrogen stream and is suitable for feeding a PEM fuel cell system.

In this experimental study the water gas shift (WGS) reaction is considered as a particular application of a catalytic membrane reactor (CMR). Experiments on the WGS reaction were carried out using a composite palladium membrane obtained by coating an ultrathin double-layer palladium film on the inner surface of the support of a commercial tubular ceramic membrane by a so-called co-condensation technique. The best operating conditions were determined at various H20/C0 molar ratios, temperature, Plumen, gas feed flow, and with and without nitrogen sweep gas. For a non-porous stainless steel tube and for the commercial ceramic membrane having the same geometrical dimensions, the conversion results are always lower than the equilibrium value. For the composite palladium membrane, the conversion also depends on the flow of the sweep gas utilized. For example, using a nitrogen sweep gas flow of 28.2 cm3/min, the maximum conversion value reaches 99.89%. The study of the effect of temperature on conversion of carbon monoxide in the WGS reaction shows that at higher reaction temperature, the thermodynamic equilibrium conversion of CO decreases. In contrast for the CMR considered in this work, there is a maximum conversion value around 600 K. This value is a compromise between the kinetic rate of the reaction (which increases with increasing temperature) and thermodynamic considerations for the WGS reaction. The effect of the time factor (W/F) on conversion of CO, with and without sweep gas at three different temperatures (595, 615 and 633 K) shows that at greater W/F there are correspondingly higher values of the CO conversion for each temperature considered. For each temperature there is a slight effect of the sweep gas, and this is higher at 595 K. The good performance of the composite ceramic-palladium membrane is confirmed by a comparison with experimental results recently presented in the literature for the same reaction. Reaction tests have been carried out for a feed mixture also. In this case, however, the resulting values are always below the equilibrium ones.

The water–gas shift (WGS) reaction in membrane reactors has been widely studied by several authors. From these works, the increase of the CO conversion above the equilibrium values appears to be possible when hydrogen is removed through the membrane. However, to date, this feasibility has been verified mostly when feeding pure reagents to the reactor, although in an industrial context the feed normally contains several other compounds. The objective of this work has been to analyse the effect of the feed composition on the membrane reactor efficiency in order to determine the best conditions in terms of CO conversion. At this purpose, experimental tests with mixtures of different compositions have been carried out in three different systems of reaction: (1) traditional fixed-bed reactor; (2) membrane reactor with mesoporous ceramic membrane; (3) membrane reactor with palladium membrane. The experiments included permeation (for the membrane reactors) and reaction tests. The experimental results obtained with the various systems of reaction have been compared. A mathematical model has been also formulated for the different type of reactors used in order to verify the experimental results obtained. From the work carried out it can be concluded that by using the palladium membrane reactor it is possible to overcome the equilibrium conversion. Moreover, a complete conversion has been achieved for one of the mixtures fed to the reactor.

The reaction of methane steam reforming was carried out in both a traditional reactor (TR) and a membrane reactor (MR). The membrane consisted of a 50-µm-thick pinhole-free palladium/ silver alloy. To investigate the enhancement of the methane conversion in the steam reforming reaction in an MR, the effects of various kinds of sweep gas (hydrogen, nitrogen, carbon monoxide, air, oxygen, and steam), as well as no sweep gas, were analyzed as a function of temperature at different molar flow rates of the sweep gas used. The dependence of the methane conversion on increasing H2O/CH 4 feed ratio was also studied. Experimental results in terms of methane conversion for the MR were compared with those obtained using a TR and literature data.

This contribution aims to refer first results obtained by the SOILCONSWEB (EU LIFE?) project which deals with a web based spatial decision support system embedding digital soil mapping engines. The aim of the project is to develop, to test and to apply a tool to support (stakeholders) decisions on landscape issues aiming at both the best soil conservation/land management and an easy landscape implementation of some important but complex environmental EU directives and regulations. In fact, often environmental directives/regulations (such as those by EU) have an intrinsic complexity because they apply to soils and landscapes which have the well recognized "multiple functions" as a fundamental feature. Then it is not surprising that this decision support system requires to include and to mix many different high quality information, engines and processing units in order to be successfully applied. Moreover the tool will also integrate the classical top-down decisions with the bottom-up contributions towards a sustainable landscape planning and managing. In this paper we employed Digital Soil Mapping procedures to obtain the spatial distribution of soil features/functions but also to incorporate any new (certified) analysis performed and uploaded by farmers. The SOILCONSWEB will automatically include new records by updating spatial models. © 2012 Taylor & Francis Group.

The study addresses the biophysical dimension of adaptation. It illustrates and applies a framework to evaluate options for adaptation by identifying cultivars optimally adapted to expected climate conditions, building on existing crops intra-specific biodiversity. The aim is to reduce the vulnerability of current production systems without altering the pattern of current species and cultivation systems. Adaptability is assessed through a three-step approach that involves: 1) evaluation of indicators of expected thermal and hydrological conditions within the specific landscape and production system; 2) determination, for a set of cultivars, of cultivar- specific thermal and hydrological requirements to attain the desirable yield; 3) identification, as options for adaptation, of the cultivars for which expected climate conditions match the climatic requirements. The approach relies on a process-based simulation model of water flow in the soil-plant-atmosphere system for the calculation of hydrological indicators. Thermal indicators are derived by means of phenological models. Empirical functions of cultivars yield response to water availability are used to determine cultivar-specific hydrological requirements, whereas cultivars thermal requirements are estimated through phenological observations. In a future climate case (2021-2050) three case-studies are analyzed: 1) a system dominated by rain-fed crops (olive, winegrapes, durum wheat) in a hilly area of southern Italy; 2) irrigated fruit crops (peach, pear) in the Po Valley; 3) maize and tomato crop in an irrigated plain of southern Italy. Cultivars adapted to the future climate have been identified for rain-fed crops (e.g. 5 olive cvs). For irrigated crops we have evaluated adaptability for optimal and deficit irrigation schedules, accounting for site-specific soils hydrological properties. Options for adaptations have been identified as a combination of cultivars, soils and irrigation schedules (e.g 2 tomato cvs and 3 maize hybrids have been identified as options for adaptation at scarce water availability). Moreover, in the case of fruit crops, accounting for phenological changes highlighted the impact on irrigation water requirements of the interaction between phenology and the intra-annual distribution of precipitation.

The COVID-19 pandemic has disrupted the global food supply chain and exacerbated the problem of food and nutritional insecurity. Here we outline soil strategies to strengthen local food production systems, enhance their resilience, and create a circular economy focused on soil restoration through carbon sequestration, on-farm cycling of nutrients, minimizing environmental pollution, and contamination of food. Smart web-based geospatial decision support systems (S-DSSs) for land use planning and management is a useful tool for sustainable development. Forensic soil science can also contribute to cold case investigations, both in providing intelligence and evidence in court and in ascertaining the provenance and safety of food products. Soil can be used for the safe disposal of medical waste, but increased understanding is needed on the transfer of virus through pedosphere processes. Strengthening communication between soil scientists and policy makers and improving distance learning techniques are critical for the post-COVID restoration.

Adoption of zero-tillage practices with residue retention in field crops has been introduced as an alternative soil-management technique to counteract the resource degradation and high production costs derived from intensive tillage. In this sense, the biophysical models are valuable tools to evaluate and design the most suitable soil-management technique in view of future climate variability. The aim of this study was to use the ARMOSA process-based crop model to perform an assessment of tillage (T) and no-tillage (No-T) practices of durum-wheat-cropping systems in the Campania region (South of Italy) under current and future climate scenarios. First, the model was calibrated using measurements of soil water content at different depths, leaf area index, and aboveground biomass in the T and No-T treatments during the 2013–2014 season. Then, the model was further applied in the T and No-T treatments to future climate data for 2020–2100 that was generated by the COSMO-CLM model using the RCP4.5 and 8.5 paths. Results of the calibration depicted that the model can accurately simulate the soil-crop-related variables of both soil-management treatments, and thus can be applied to identify the most appropriate conservation agricultural practices in the durum-wheat system. The simulation of soil water content at different depths resulted in small relative root mean square errors (RRMSE < 15%) and an acceptable Pearson’s correlation coefficient (r > 0.51); and the goodness-of-fit indicators for simulated LAI and AGB resulted in acceptable RRMSE (RRMSE < 28%), and high r (r > 0.84) in both soil-management treatments. Future climate simulations showed that No-T management will deliver 10% more wheat yield than the T, with an annual average 0.31% year−1increase of soil organic carbon, and an increase of 3.80% year−1for N uptake, which can diminish the N leaching. These results suggest that No-T could be implemented as a more resilient management for farming system in view of climate uncertainty and scarcity of resources. Therefore, these findings support the potential of the ARMOSA model to evaluate the soil-crop response of the durum-wheat system under different management conditions and to design appropriate soil-management practices for current and future climate predictions.

A general unique structural vision of transport phenomena in Reverse Osmosis (RO) and Nanofiltration (NF) membranes is discussed. The most common models for RO (such as the solution-diffusion and/or the Spiegler-Kedem model) and for NF membranes (the extended Nernst-Planck equation) are introduced as particular cases of the general “statistical-mechanical theory” of membrane transport developed by Mason and Lonsdale in 1990. The use of that approach is recommended to develop a structural model when the physical meaning of the parameters is desired. The typical trends of solute rejection and of the total volume flux in RO processes are discussed and the meaning of the model parameters is explained. NF modelling is presented according to the conditions of the porous vision of the Donnan-Steric-Pore-and-Dielectric-Exclusion model (DSPM-DE). The complexity of the physical phenomena involved in the partitioning mechanisms is widely discussed: mechanisms of charge formation and of dielectric exclusion (image forces and Born partitioning) are described in detail. The general DSPM-DE model is adapted for the case of neutral solutes and for electrolyte mixtures: for each case, the basic equations are developed and the typical approximations are presented. The procedures for membrane parameters calculations are introduced and a detailed discussion about the recommended correct method for data elaboration is presented. The final discussion is focused on the problems not yet completely solved as well as on the possible future trends.

The consumption of fossil fuels, as the main energy sources, is associated with progressive increase of severe environmental problems such as climate change, global warming, and greenhouse effect. Hydrogen is one of the most promising energy carriers, and if produced from renewable sources, it is ideal to replace currently used fossil fuels, consequently reducing toxic emissions. This chapter focused on the technologies to obtain hydrogen from biomass exploited as renewable and sustainable energy resource, with special reference to thermal gasification. A technoeconomic and life cycle analysis of different hydrogen production processes taken into account is also included.

Valorization of organic wastes (OWs), including agricultural residues, agro-industrial, and organic municipal waste, could be an attractive approach for achieving bioenergy and biochemicals. The integration of biorefinery with membrane technology represents a useful tool for a fast downstream OWs processing, with zero waste generation. However, OWs have heterogeneous properties that need to be preprocessed before their transformation. Therefore a preliminary pretreatment is required. Also, the bioprocessing of OW should be controlled for the production of different bio-based products. Among the parameters strongly affecting the production process, there are feeding rate, pH, and temperature. In addition, technical and commercial feasibility of the integrated approach need to be evaluated. This chapter reviews the biotransformation of OW into several bioproducts, recommending integrated biorefinery approach for the subsequent production of bioproducts. A brief review on membrane technology and its application in downstream processing is provided. Future prospects of integrated biorefinery and membrane technology are proposed.

Despite the development of new convective stationary phases with improved binding capacity, the use of membrane chromatography for protein capture is still limited to niche applications, although for the purification of large biomolecules, membrane adsorbers are gaining an increased popularity. As for all membrane processes, a good understanding of material properties and of the kinetic and transport phenomena involved will help to show the limitations of current membrane materials and modules. Indeed, the development of novel membrane materials with improved properties and functionalities, together with the design of more efficient membrane chromatography modules, is the key issue that researchers need to address as for this technology to make a breakthrough.

This chapter briefly presents the fundamentals of the processes of heterogeneous photocatalysis (PC). In particular, Langmuir–Hinshelwood and Eley–Rideal models that are often used to model the kinetics of heterogeneous photocatalytic reactions are described together with other models and equations derived. Moreover, some considerations about the dependence of the rate of PC on the light intensity, pH, and photocatalyst modification are done. Methods for photoreactor modeling are described, and the coupling of PC with other advanced oxidation processes (AOPs) using H2O2, O3, and peroxydisulfate is discussed. It is highlighted that coupling different technologies results in a real intensification of the global efficiency only for specific ratios of the rates of the single processes. The suitability of the practical application of the AOPs must be based on a precise process efficiency assessment, which, as the results show, is a challenging but necessary task.

In the present chapter it is shown how photocatalytic membrane reactors utilizing membrane processes, which are not pressure driven, can exploit various mechanisms to obtain a substantial improvement of the process. The fundamentals of this particular type of membrane reactors are reviewed including the effects of the most important parameters and the methods and rules of coupling photocatalysis and membrane separation. The survey of the studies on photocatalytic membrane reactors (PMRs) utilizing pervaporation, dialysis, membrane contactors and membrane distillation offers the opportunity of discussing the advantages with respect to PMRs adopting pressure driven membrane processes. Indeed, the strengths of the investigated processes are the high retention of the photocatalytic powders with minor fouling problems, the simpler and cheaper apparatuses and the possibility of selectively removing or recovering the products. Finally, the reasons, which currently limit the application of these membrane reactors, are illustrated together with the very interesting future perspectives.

The development of renewable wind and solar energy, which is by nature intermittent, has lead to solutions being developed for the storage of excess electricity. One technical solution is the possibility of producing hydrogen through the electrolysis of water. In such a scheme, storing the hydrogen is equivalent to storing electricity, which could be used for fuel cells. In the main cycle of hydrogen production–storage–use, geological storage is a fundamental element. Geological storage may also be needed in several other situations, when hydrogen is produced in other ways, e.g., from fossil fuels (coal gasification) or from water by thermal electrolysis (in nuclear plants), and used for different objectives, e.g., to be injected into natural gas pipelines, to turn gas-fired turbines, or to meet the needs of the petroleum refinery and other industrial consumers. All these situations may require massive storage solutions to optimize production by freeing supply from consumer demand, increasing energy production efficiency, and limiting environmental impacts. We have only a few examples of large-scale geological hydrogen storage, and the results in the field are still poor. New data reveal that the behavior of underground hydrogen is more complicated than expected, essentially due to its high mobility and lightness, which cause nontrivial hydrodynamic effects, and due to its high reactivity in the presence of microorganisms, which causes its loss. The aim of this chapter is to give an overview of the main scientific problematic related to underground hydrogen storage. With respect to the preceding review published by the author in 2010, new information obtained from several research projects recently launched in Europe is considerably richer.