Hg Porosimetry Research Articles

Enhancing Aluminium‐Ion Battery Performance with Carbon Xerogel Cathodes

AbstractThis study presents groundbreaking results in the field of rechargeable aluminium‐ion batteries, achieving stable capacities exceeding 300 mAh g−1 for more than 300 cycles. The key to this achievement lies in the utilization of tailor‐made carbon materials and a urea‐AlCl3‐based electrolyte. The article investigates the optimal physicochemical properties of the active material necessary for effective electrodes for these aluminium‐ion batteries. This investigation employs a wide range of materials characterization techniques (XRD, SEM‐EDX, N2 adsorption‐desorption isotherms, Hg porosimetry, XPS, FTIR, Raman and TEM‐EDX) and electrochemical performance analyses to delve into the subject. These findings represent a significant improvement in the capacity of aluminium‐ion batteries, bringing us closer to their implementation and commercialization. This achievement is attributed to the utilization of readily available, cost‐effective, and non‐corrosive materials. The ability to customize carbon xerogels and the use of the urea‐AlCl3 electrolyte offer promising avenues for the practical implementation of these advanced battery technologies, leading to further enhancements in their performance and widespread adoption in various applications.

Removal of Mo(VI), Pb(II), and Cu(II) from wastewater using electrospun cellulose acetate/chitosan biopolymer fibers

Environmentally friendly polymers such as cellulose acetate (CA) and chitosan (CS) were used to obtain electrospun fibers for Cu2+, Pb2+, and Mo6+ capture. The solvents dichloromethane (DCM) and dimethylformamide (DMF) allowed the development of a surface area of 148 m2 g−1 for CA fibers and 113 m2 g−1 for cellulose acetate/chitosan (CA/CS) fibers. The fibers were characterized by IR-DRIFT, SEM, TEM, CO2 sorption isotherms at 273 K, Hg porosimetry, TGA, stress-strain tests, and XPS. The CA/CS fibers had a higher adsorption capacity than CA fibers without affecting their physicochemical properties. The capture capacity reached 102 mg g−1 for Cu2+, 49.3 mg g−1 for Pb2+, and 13.1 mg g−1 for Mo6+. Furthermore, optimal pH, adsorption times qt, and C0 were studied for the evaluation of kinetic models and adsorption isotherms. Finally, a proposal for adsorbate-adsorbent interactions is presented as a possible capture mechanism where, in the case of Mo6+, a computational study is presented. The results demonstrate the potential to evaluate the fibers in tailings wastewater from copper mining.

Initiation and development of tectonic stylolite – Vein system in micritic limestone (Les Matelles, France)

In this study, we describe the characteristics of tectonic stylolites and related veins affecting a low-porosity micritic limestone (Jurassic carbonates, Les Matelles, South of France) in order to unravel the conditions of initiation and interaction between pressure-solution and fracturing in such rock. Field description, various petrographic and microstructural investigations (cathodoluminescence, SEM imaging, EBSD analysis), and petrophysical/geochemical analyses (Hg porosimetry, XRD, EPMA) are used. We document that pressure-solution initiates at micropores and propagates along calcite grain contacts, connecting surrounding stylolite micro-segments, and progressively concentrates insoluble material such as clays and siliceous particles. The dissolved material is evacuated to the veins where the newly-formed porous space is progressively filled by calcite cement. These deformation processes are strictly restricted to the stylolitic interface and veins, as no modification of porosity or grain deformation is detected in the neighboring host rock. This is due to the low-permeability of the surrounding host rock impeding the evacuation of dissolved material and fluids through interstitial porosity around the pressure-solution zone, leading to overpressure and veins formation. The water release and microporosity caused by diagenesis of the clay fraction (smectite-illite transformation) are discussed as key diagenetic processes instigating the conditions of pressure-solution initiation, then tectonic stylolite formation in low-porosity limestones.

Structural design and particle size examination on NiO-CeO2 catalysts supported on 3D-printed carbon monoliths for CO2 methanation

3D-printed high-surface carbon monoliths have been fabricated and tested as catalyst supports of CO2 methanation active phases (NiO-CeO2, 12 wt% Ni). The carbon carriers show a developed microporosity and good adherence to the catalytic phases of NiO-CeO2, showing great stability and cyclability. Two monolith designs were used: a conventional parallel-channeled structure (honeycomb) and a complex 3D network of non-linear channels built upon interconnected circular sections (circles), where flow turbulences along the reactant gas path are spurred. The effect of the active phases particle size on the catalyst distribution and the overall performance has been assessed by comparing NiO-CeO2 nanoparticles of 7 nm average (Np), with a reference counterpart of uncontrolled structure (Ref). The improved radial gases diffusion in the circles monolith design is confirmed, and nanoparticles show enhanced CO2 methanation activity than the uncontrolled-size active phase at low temperatures (< 300 ºC). On the contrary, the Ref catalysts achieve higher CH4 production at higher temperatures, where the reaction kinetics is controlled by mass transfer limitations (T > 300 ºC). SEM and Hg porosimetry evidence that nanoparticles are deposited at deeper penetration through the narrow micropores of the carbon matrix of the monolithic supports, which tend to accumulate on the channels surface remaining more accessible to the reactant molecules. Altogether, this study examines the impact of the channel tortuosity and the active phase sizing on the CO2 methanation activity, serving as ground knowledge for the further rational and scalable fabrication of carbon monolith for catalytic applications.

Structural and mechanical optimization of porous alumina structures fabricated by carbon sacrificial template

The Taguchi method is used to optimize the manufacture of porous alumina made through reactive spark plasma sintering and carbon sacrificial template. The goal is to design a new versatile procedure that allows the fabrication of porous alumina with tailored physical properties. The structural and mechanical properties taken as target parameters were the subtle combination of porosity and Young’s modulus of the human cortical bone: typical pore size ¿100μm, and Young’s modulus in the range of 3–30 GPa. The input factors of the Taguchi method are wt.% of carbon, sintering time, calcination heating rate, and final heat treatment. Hg porosimetry, electron microscopy, uniaxial compression and computer aided tomography were used for the characterization of the porosity, pore size distribution, pore interconnectivity, and Young’s modulus. Finally, according to the conclusions of the Taguchi analysis, the parameters of the process were changed for the fabrication of the new samples with optimized properties. Highly porous structures with 90% interconnectivity, Young modulus of 5.5 ± 1.1 GPa, and compression strength of 49 ± 20 MPa, were obtained, successfully emulating the targeted properties.

Influence of the acrylamide-based monomer on the sintering of ceramics shaped by gelcasting

Alumina ceramics were prepared by gelcasting, based on an in-situ polymerization that promotes the formation of homogeneous green ceramic parts and allows the preparation of complex shapes and/or large-size ceramics. The influence of the monomer on the sintering behaviour of alumina pellets has been studied by considering three acrylamide-based monomers, i.e. acrylamide (AM), methacrylamide (MAM) and dimethylacrylamide (DMAA). Slurries with an alumina solid content of 50 vol% have been cast and pre-sintered pellets (1000 °C) with relative densities around 55% were obtained. These presintered pellets exhibit different granular packing, depending on the initial monomer used, as demonstrated by X-ray tomography, SEM and Hg porosimetry analyses. This results in significant differences in sintering behaviour, giving rise to very different final densities after 1 h sintering at 1530 °C: from 88% to 98%. This behaviour is described in terms of shrinkage rate, linked to the granular packing induced by the gelation process.

Hard-templated macroporous alumina with thick mesoporous walls: The key factors of pore formation

This paper focuses on the key factors contributing to pore formation in hard-templated macroporous alumina. Special attention is paid to the formation of a connected pore structure. Two series of samples were prepared, each with different content of the polymeric template. The pore structure of alumina was designed using polystyrene and acrylic copolymers as hard templates. Alumina differed in crystallite morphology (round-like and rod-like) and pore structure (bottleneck-like and slit-like). The templates differed in particle size (100 and 250 nm) and physical state (powder and suspension). All the samples were characterized by N2 adsorption, Hg porosimetry, XRD, and SEM. The data obtained indicate that a hard template made of polymeric particles has the following functions: fixing the pore size and shape, sintering small pores of the material, and creating additional channels to connect macropores. Regardless of the type of polymeric template and Al2O3 precursor, a connected pore system can be formed by adding more than 20 wt% of the template.

Change of safety by main aging mechanism – A multi-sensor accelerating rate calorimetry study with commercial Li-ion pouch cells

The safety of Li-ion batteries is the most critical of many important characteristics and must be carefully considered. However, depending on the aging conditions, safety of batteries can change drastically. We had recently introduced ARC-MS as a new tool for safety investigations, which is an updated accelerating rate calorimeter (ARC) combined with a mass spectrometer (MS). Additionally, our ARC-MS setup is equipped by seven more low cost sensors (temperature, voltage, resistance, audio, strain, and transmitted and reflected ultrasound). In this paper, the dependence of safety on the dominant aging mechanism as a function of aging temperature, and state-of-health (SOH) is investigated on the example of 3.3 Ah commercial pouch cells. The ambient temperature during aging has a strong influence on the dominant aging mechanism (Li plating or SEI growth) of this cell as shown by Arrhenius plots of the aging rate and Post-Mortem analyses (ICP-OES, SEM, EDX, Hg porosimetry, STA) of aged cells. Our in-depth evaluation shows that different sensors can provide indications of safety relevant events (onset of swelling, onset of self-heating, cell venting, stable exothermic reactions, separator melting, and thermal runaway) in the cells independently. Combining these low-cost sensors might be a solution for detection of unsafe cells in applications.

Phase relations in heat treated sodium borosilicate glasses

Sodium borosilicate glasses are processed to porous glasses as well as to Vycor™ type glasses via phase separation and selective leaching. Both materials consist mainly of SiO2. Thermal treatment inducing phase separation is crucial for microstructure development. Sodium borosilicate glasses with molar compositions of 8Na2O.21B2O3.71SiO2 and 8Na2O.28B2O3.64 SiO2 were melted, rapidly cooled and investigated by thermal analysis and scanning electron microscopy. The glasses were thermally treated for 120 h at 630 to 730°C, and then leached, first for 72 h in 0·1 M HCl at 60°C, and subsequently for 4 h in 0·5 M NaOH at 30°C. X-ray fluorescence was applied to characterise the chemical compositions. Microstructure development was first analysed by differential thermal analysis and dilatometry, and the pore structure was characterised by Hg porosimetry and N2 adsorption. Heat treated glasses were then analysed by low voltage scanning electron microscopy, combined in one case with chemical analysis by energy dispersive x-ray analysis. The results are discussed with respect to phase relations. After long term heat treatment, at least three phases exist in two independent metastable two-phase equilibria on different size and time scales.

Biodiesel production from rapeseed oil over calcined waste filter cake from sugar beet processing

A solid catalyst was prepared from waste filter cake (WFC) from a sugar beet processing plant and used, after calcination at 900 °C within 2 h, for biodiesel production from rapeseed oil and methanol. The calcined WFC (CFC) catalyst was characterized by XRF, FTIR, XRD, TGA/DTG, TPDe, TPD-CO2, SEM, N2 physisorption, and Hg porosimetry. The CFC is a CaO-based catalyst with a rigid, sustainable macroporous structure with the largest particles of 2.0 × 0.5 µm, a specific surface area of 7.3 m2/g, and a basicity of 0.27 mmol/g. It provides high conversion of 97.9% in 1 h at the methanol-to-oil molar ratio of 9:1, the temperature of 60 °C, and the catalyst loading of 10% of the oil mass. Its catalytic efficiency is comparable to the WFC-based nanocatalysts and CaO-based catalysts from natural sources. CFC was reused twice with a negligible decrease in catalytic activity, ensuring a FAME content above 97% in 1 h. The biodiesel produced from rapeseed oil over the CFC catalyst has good fuel properties that fulfill most of EN 14214. Therefore, WFC is a promising source of a low-cost, highly active, basic, and environmentally friendly CFC catalyst, which could reduce biodiesel production costs. From this point of view, this catalyst has great potential for developing the process at the commercial level.

Detection of Li Deposition on Si/Graphite Anodes from Commercial Li-Ion Cells - a Post-Mortem GD-OES Depth Profiling Study

A new semi-quantitative method based on Post-Mortem glow discharge optical emission spectroscopy (GD-OES) depth profiling was developed to detect Li deposition on Si/graphite anodes. By means of the detected amounts of Li, Si and O in the GD-OES depth profiles, a corridor is determined, in which the minimum amount of Li deposition is found. Three different commercially available 18650 cell types containing Si/graphite as anode active material were acquired to evaluate the newly developed method. Those three cell types were initially characterized in detail by means of SEM/EDX, GD-OES, ICP-OES, and Hg porosimetry regarding their cell chemistry and electrode properties. One cell type was a high-power cell due to its high anode porosity and low anode coating thickness. The other two cell types were high-energy cells, which have thick anode coatings and low porosities.We aged the cells at 45 °C until their SOH was 80% and analysed the aging behaviour using SEM, DVA, GD-OES, and in coin half-cells. GD-OES depth profiling revealed that no Li plating occurs during cycling aging at 45 °C. Contrary to this, Li plating was detected on the anodes of all three cell types by the new GD-OES method after the high-power cell was aged at -20 °C and the high-energy cells were aged to 0 °C.Cells, which were previously aged at 45 °C until 80% SOH have afterwards been cycled under the same conditions, which led to Li plating in the fresh cells. Cell types exhibiting predominantly loss of anode active material (LAAM) as aging mechanism during the first aging at 45 °C, still suffered from Li plating during the second aging. However, if the main aging mechanism during the initial aging was loss of cyclable Li inventory (LLI), the cells did show a significantly reduced tendency for Li plating, even though the same conditions caused Li plating in the fresh cells.Analysis of the aged anodes using coin half-cells revealed that the loss of anode material was caused by the deactivation of Si anode material. SEM images of the anode cross-section indicate that the deactivation is most likely mainly induced by the formation of a thick film surrounding the Si particles.In combination with complementary methods like SEM, ICP-OES, and coin half-cell analysis, the newly developed GD-OES method yields in profound understanding of the aging behaviour of state-of-the-art Li-ion cells contain Si/graphite anodes. Figure 1

Determining Mechanical Moduli of Disordered Materials with Hierarchical Porosity on Different Structural Levels.

The impact of synthesis parameters and structural properties, respectively, on mechanical properties of porous materials on different structural levels provides valuable information for designing materials for specific applications. Within this study, we apply two nonstandard approaches for determining the mechanical properties of the mesoporous backbone phase in a series of disordered SiO2-based monolithic materials possessing hierarchical meso-macroporosity, that is, deformation upon mercury porosimetry and in situ dilatometry during nitrogen adsorption analysis. By using ordered porous model materials, the latter method has been recently proven to provide reliable mechanical moduli. This concept was now applied to a SiO2 monolith developed for high-performance liquid chromatography exhibiting disordered hierarchical meso- and macroporosity, as well as a series of analogue phenyl-modified meso-macroporous SiO2 monoliths with up to 36.1 at% organic modification. The phenyl group was introduced by adding phenyltrimethoxysilane to the sol-gel mixture. The study aimed at investigating in detail the impact of the organic modification on the morphology of the porous solid and the resulting mechanical properties. The study shows that both Hg porosimetry and in situ dilatometry performed during N2 adsorption at 77 K provide similar and reasonable moduli of compression for the mesoporous backbone of the silica materials investigated. These data were compared with moduli of the macroscopic sample as determined from sound velocity measurements by describing the fully connected macroporous backbone with a foam model. The comparison reveals an otherwise overseen side effect of the organic modification of the silica framework: in contrast to the pure reference SiO2 meso-macroporous monoliths, the hybrid material is composed of a more particulate morphology on the mesoscale, that is, mesoporous particles and corresponding necks between them are formed, which results in significant softening of the porous solid on the macroscale.

Silicon Oxycarbide Porous Particles and Film Coating as Strategies for Tenofovir Controlled Release in Vaginal Tablets for HIV Prevention.

Sustained release of antiretroviral drugs is currently the most encouraging strategy for the prevention of the sexual transmission of HIV. Vaginal tablets based on hydrophilic gelling polymers are an interesting dosage form for this purpose, since they can be developed to modify the release of the drug depending on the tablet swelling. Tenofovir is a drug with proven activity in the prevention of HIV-1 infection, and it is possible to have it loaded in the surface of γ-aminopropyl trimethoxy silane-functionalized oxycarbide particles. These particles can be incorporated into the tablets, thus providing a sustained release of the drug. Moreover, the presence of the particles modifies the microstructure of the gel formed, as observed in scanning electron microscopy and Hg porosimetry studies, resulting into a gel with a narrow pore size distribution between 10 and 100 µm. This implies a lower volume of fluid incorporated into the gel during swelling studies, and therefore improved mucoadhesion times in ex vivo test. The coating of the formulations with Eudragit® RS modifies the swelling behavior of the tablets, which not only is decreased in magnitude but also extended in time, and as consequence the drug release is also prolonged for up to 7 days.

Aerogel-Derived Fe-N-C Catalysts for Oxygen Electro-Reduction. Linking Their Pore Structure and PEMFC Performance

Iron-based catalysts are intensely investigated for application at the cathode of proton exchange membrane (PEM) and, more recently, of anion exchange membrane fuel cells (AEMFC). Besides optimising their kinetic activity toward the oxygen reduction reaction (ORR), the design and control of their pore structure plays a key role in achieving the highest possible performance in fuel cell. Fe-N-C catalysts derived from the metal-organic framework ZIF-8 are highly active but also mainly microporous, which can lead to mass-transport issues. The silica templating approach typically leads to slightly less active Fe-N-C catalysts, but featuring a combination of micropores and mesopores, which can facilitate mass-transport. Aerogel methods for the synthesis of Fe-N-C catalysts with a hierarchical pore size distribution has been hitherto under-investigated. In contrast to the silica templating method, it is more environmental friendly since no dissolution of a template is needed (no HF). However, highly active Fe-N-C catalysts prepared by aerogel method have not yet been reported in PEM system (even if promising results were recently obtained in rotating disk electrode [1-2]), and it is therefore also unclear if the hierarchical pore size distribution derived from this method is beneficial for improving the mass-transport properties of Fe-N-C cathodes.This presentation will first report the synthesis method and the key parameters investigated, such as the ratio of melamine to resorcinol, the nature and amount of the iron precursor, the addition of an additionnal N-rich ligand, on their ORR activity. The materials were characterized for their texture (N2 sorption, Hg porosimetry), Fe coordination (X-ray absorption and Mössbauer spectroscopy) and surface chemistry (XPS) and morphology. The most promising materials were investigated in PEMFC, for their initial power performance and durability. The results show that, by playing with these synthesis parameters, the aerogel method can yield highly active ORR catalysts (Figure 1), and can give a control on their hierarchical porosity, especially in tuning the mesoporous volume and the average pore width of mesopores. Most catalysts display an atomic dispersion of Fe, explaining their high ORR activity. The presentation will particularly discuss the link between the pore size distribution in this set of materials (micro, meso and macropores), and the mass-transport properties in PEMFC, under pure O2 or air at the cathode. Their durability will also be discussed, from accelerated stress tests performed in rotating disk electrode and/or PEMFC.Acknowledgments:This study was financially supported by the French National Research Agency under the project ANIMA (ANR-19-CE05-0039).

Improving the frost resistance of roof tiles beyond current prediction schemes

Frost resistance is an important requirement for clay roof tiles and the most difficult to keep under control during industrial production. Durability under freeze/thaw cycles is related with the capillary pore system, and current models predict the lower the open porosity and the coarser the pore size, the better the frost resistance. This implies, however, high firing temperature and rather refractory clay bodies, which are in contrast with energy and resource efficiency. Therefore, a different approach is needed to improve frost resistance of roof tiles without stressing the concept of low porosity and coarse pore size. A case-study is presented to demonstrate how excellent frost resistance can be achieved by adjusting raw materials formulation and firing schedule. Raw materials and bodies were characterized by XRF, ASTM C958 and technological properties. Both laboratory tests were performed: the products were characterized by water absorption (ASTM C67), open porosity and pore size distribution (Hg porosimetry), phase composition (XRD-Rietveld), mechanical strength (EN 538) and frost resistance (EN 539-2) up to 400 freeze/thaw cycles. Durability of roof tiles was drastically improved acting on both pore size distribution (eliminating pores <0.1 μm) and increasing mechanical strength (>13 MPa). Phase composition plays a complex role with opposite effects of new formed phases versus amorphous phase and residual clay minerals. A satisfactory target (no damages after 250 freeze/thaw cycles) was achieved firing at 900 °C (7% pores <0.1 μm) while the best performance (no damages after 400 cycles) required firing at 950 °C (<1% pores <0.1 μm). Excellent frost resistance (well beyond the standard 50 cycles) can be obtained through proper design of firing schedule and body composition, even for temperatures below 950 °C.

Fabrication of Porous Alumina Structures by SPS and Carbon Sacrificial Template for Bone Regeneration.

In this work, a procedure for fabricating porous alumina with the use of a carbon sacrificial template has been tested in order to optimize the fabrication of porous structures mimicking the porosity and mechanical properties of the human cortical bone. Two different sources of sacrificial carbon were used and compared, and different sintering and calcination routes were considered. The porosity of the alumina structures studied by Hg porosimetry revealed that the amount of porosity and the size and shape of the pores are still below the required values, although some acicular pores were clearly observed by SEM. Moreover, measured mechanical properties (Young’s modulus) remained below that of the bone, suggesting the need for further consolidation treatments. In summary, these encouraging results drive the optimization of future fabrication routes.

Evolution of Hierarchically Porous Nickel Alumina Catalysts Studied by X-Ray Ptychography.

The synthesis of hierarchically porous materials usually requires complex experimental procedures, often based around extensive trial and error approaches. One common synthesis strategy is the sol–gel method, although the relation between synthesis parameters, material structure and function has not been widely explored. Here, in situ 2D hard X‐ray ptychography (XRP) and 3D ptychographic X‐ray computed tomography (PXCT) are applied to monitor the development of hierarchical porosity in Ni/Al2O3 and Al2O3 catalysts with connected meso‐ and macropore networks. In situ XRP allows to follow textural changes of a dried gel Ni/Al2O3 sample as a function of temperature during calcination, activation and CO2 methanation reaction. Complementary PXCT studies on dried gel particles of Ni/Al2O3 and Al2O3 provide quantitative information on pore structure, size distribution, and shape with 3D spatial resolution approaching 50 nm, while identical particles are imaged ex situ before and after calcination. The X‐ray imaging results are correlated with N2‐sorption, Hg porosimetry and He pycnometry pore characterization. Hard X‐ray nanotomography is highlighted to derive fine structural details including tortuosity, branching nodes, and closed pores, which are relevant in understanding transport phenomena during chemical reactions. XRP and PXCT are enabling technologies to understand complex synthesis pathways of porous materials.

Small angle x-ray scattering to investigate the specific surface of hydrated alginate microbeads

Encapsulation of active substances in biopolymer beads becomes a widely developed approach to gain efficiency for many applications. However, the characterization of such aqueous materials in their early stage of production is very delicate regarding their textural properties. The classical tools such as gas adsorption and Hg porosimetry can hardly provide relevant information since they require the removal of water, which is yet a fundamental part of the sample that drives its structure. In this article, we used small angle x-ray scattering (SAXS) as a tool in order to determine the specific surface area (SSA) of alginate microbeads in solution. This has been made possible by a careful procedure of SAXS measurements, involving calibration samples, allowing writing intensities in absolute units. Therefore, the Porod limit theory was used to calculate the SSA from the scattering length contrast and the measured absolute intensity. In addition, we compared the SSA of microbeads obtained from pure water and from a widely used cell culture medium, and we followed the textural evolution of a water alginate sample during the first step of a gentle drying process. Our results show that SAXS should be considered as a valuable tool for physico-chemists and food formulators in order to extract in situ dimensional and textural information of hydrogels during the formulation. It enables them to figure out the real surface available for the sorption of additive or active molecules in the formulation of biopolymers such as alginates, empowering them to better control encapsulation processes.

Synthesis of porous high-temperature superconductors via a melamine formaldehyde sacrificial template.

Nanostructured high-temperature superconductors YBa2Cu3O6+δ and Bi2Sr2CaCu2O8+δ were synthesised using a melamine formaldehyde sponge as a sacrificial template, via three solution-based approaches. In the case of YBa2Cu3O6+δ, a modified Pechini method produced a material with a superconducting transition at 92 K and a specific surface area of 4.22 m2 g−1. Further analysis with Hg porosimetry determined that the sponge exhibited a porosity of 82%. In the case of Bi2Sr2CaCu2O8+δ, this method produced a material that exhibited superconductivity at 86 K with a specific surface area of 9.62 m2 g−1. Hg-porosimetry determined that the BSCCO sponge exhibited a porosity of 78%.

Pore structure and interdisciplinary analyses in Roman mortars: Building techniques and durability factors identification

Microstructural and compositional analysis of historical mortars is an active research field, not only to guarantee the use of compatible repair measures, but also to guide the design of novel efficient materials. Despite the crucial role of Roman mortars in building history, there is a significant lack of knowledge of their pore system in relation to building techniques and durability. From these premises, this research focuses on the structural mortars of the Realillo aqueduct (Archaeological Site of Baelo Claudia, Spain). This construction is especially interesting from a durability point of view, as in addition to being in a windy coastal area, the water-proof potential of the material is a major issue. Complementary experimental techniques (petrography, computed tomography, X-ray fluorescence, X-ray diffraction (micro and conventional), thermal analysis, pycnometry, physisorption, Hg porosimetry, and SEM-EDS) are applied within a multidisciplinary approach, including the Vitruvian guidelines and comparative analysis with coetaneous buildings. The size and shape of the pores and the porous volume distribution have been linked to hydraulicity, and to cohesion and weathering resistance. Total and open porosity can be related to waterproof worsening, and the entrapped air pores detected could indicate inadequate placement. The shrinkage cracks can be related to the sea sand aggregate. Thermal analysis and C-A-S-H gel indicate hydraulic phases, but with different hydraulicity levels. This variation could be related to the non-high-purity limestone and/or to the recipe. The differences in binder/aggregate ratios and petrographic classification confirm the distinct compositions. Non-standardized manufacturing or building stages could be related to compositional variations. This research has provided significant insights into durability and manufacturing issues by integrating a micro–macro pore structure study within multianalytical and interdisciplinary research. The method may be used as a complementary procedure to characterize historical mortars. As upgrading/degrading durability factors were obtained, a conservation campaign could be designed. In addition, knowledge about historical building techniques and materials has been enriched.