Surface modification of mesoporous silica with organo-siloxane reagents enables precise tuning of material properties while preserving the identity and structural integrity of the porous structure. Although amino silanization is a well-established technique, the process remains suboptimized, with no standardized protocol yet available for the obtaining of uniform silane layers on silica surfaces.In this work, calcined mesoporous silica nanoparticles have been functionalized using three different aminosilanes, (3-aminopropyl)triethoxysilane (APTES), N-[3-(trimethoxysilyl)propyl]ethylenediamine (EDAS), and N-[3-(trimethoxysilylpropyl)]diethylenetriamine (DETAS), using a water-based procedure. The proposed methodology has been compared to a solvent-free functionalization method. The materials have been characterized through thermogravimetric analysis (TGA), X-ray diffraction (XRD), nitrogen adsorption-desorption isotherms, Fourier-transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS), X-ray photoelectron spectroscopy (XPS), and solid-state nuclear magnetic resonance (SSNMR).Water-assisted functionalization leads to significantly greater organosilane incorporation compared to solvent-free methods. EDAS and DETAS exhibit controlled and homogeneous surface modification (46 and 24% weight loss increase respectively) while, with APTES, highest organosiloxane loading is achieved (118% weight loss increase), although evidence of oligomerization, and coating with additional organo-siloxane mesoporosity on the nanoparticle surface, whose formation is favoured by a five-terms intermediate, is detected.Organosilane hydrolysis mechanisms is governed by the spatial arrangement of amino groups and molecular structure of organosilane itself, with water playing a vital role in modulating reaction kinetics. These findings, discussed in detail, provide important insights for the precise design and optimization of silica-based nanomaterials in future technological applications.

Mesoporous silica nanoparticles (MSNs) are promising drug carriers for cancer therapy. Their functionalization with ligands for specific tissue/cell targeting and stimuli-responsive cap materials for sealing drugs within the pores of MSNs is extensively studied for biomedical and pharmaceutical applications. The objective of the present work was to establish MSNs as ideal nanocarriers of anticancer drugs such as 5-FU and silymarin by exploiting characteristics such as their large surface area, pore size, and biocompatibility. Furthermore, coating with various biopolymeric materials such as carboxymethyl chitosan-dopamine and hyaluronic acid-folic acid on their surface would allow them to play the role of ligands in the process of active targeting to tumor cells in which there is an overexpression of specific receptors for them. From the results obtained, it emerged, in fact, that these hybrid nanoparticles not only inhibit the growth of glioblastoma and breast cancer cells, but also act as pH-responsive release systems potentially useful as release vectors in tumor environments.

Poly Lactic Acid / Poly Butylene Adipate-co-Terephthalate blends are used as packaging green materials since they constitute hydrophilic and biodegradable plastic. With the aim of improving the mechanical characteristics of such blends as biodegradable packaging materials for food products the addition of starch has been considered. In silico test performed by classical molecular dynamics highlighted that the addition of starch can reinforce the polymeric structure via starch-polymer interactions, suggesting that starch can be a suitable material to be added to the Poly Lactic Acid / Poly Butylene Adipate-co-Terephthalate blend to obtain more resistant packaging materials. Experimental analysis of the mechanical properties of the polymeric blend containing different amounts of starch confirmed what foreseen by MD, highlighting an increase of Young modulus and glass transition as a function of added starch. The coupled theoretical/experimental approach constitutes added value of the present work, furnishing important data on the reinforcement of the packaging material performances and a molecule-based interpretation and comprehension of the observed phenomenon.

Enhanced oil recovery (EOR) processes are technologies used in the oil and gas industry to maximize the extraction of residual oil from reservoirs after primary and secondary recovery methods have been carried out. The injection into the reservoir of surface-active substances capable of reducing the surface tension between oil and the rock surface should favor its extraction with significant economic repercussions. However, the most commonly used surfactants in EOR are derived from petroleum, and their use can have negative environmental impacts, such as toxicity and persistence in the environment. Biosurfactants on the other hand, are derived from renewable resources and are biodegradable, making them potentially more sustainable and environmentally friendly. The present review intends to offer an updated overview of the most significant results available in scientific literature on the potential application of biosurfactants in the context of EOR processes. Aspects such as production strategies, techniques for characterizing the mechanisms of action and the pros and cons of the application of biosurfactants as a principal method for EOR will be illustrated and discussed in detail. Optimized concepts such as the HLD in biosurfactant choice and design for EOR are also discussed. The scientific findings that are illustrated and reviewed in this paper show why general emphasis needs to be placed on the development and adoption of biosurfactants in EOR as a substantial contribution to a more sustainable and environmentally friendly oil and gas industry.

Climate change, driven by elevated atmospheric CO2 levels, is recognized as a persistent and significant issue of the 21st century. Consequently, the creation of effective and suitable methods to decrease atmospheric CO2 emissions is urgently and critically needed. Various techniques, including membrane separation, chemical absorption, and adsorption, are currently employed to capture CO2. In particular, processes based on physisorption are noted for their energy efficiency and cost-effectiveness, making the choice of an effective adsorbent essential. Metal-organic frameworks (MOFs), which are porous structures formed from metal ions and organic linkers, have emerged as promising and adaptable solutions for advanced CO2 capture initiatives. These materials hold potential for application across a broad spectrum of domains, including gas adsorption and separation, catalysis, electron luminescence, magnetism, as well as in drug delivery and the health sciences. So far, MOFs have mainly been developed as promising materials for CO2 adsorption due to their large capacity for adsorption of gases and easy tailor ability of their structures, and metal sites. In this study, the fabrication of specific devise for controlling environmental remediation of CO2 through CCS techniques has been described also highlighting their potential utility for CO2 adsorption purposes. First of all, the synthesis of HKUST-1, a solid belonging to the class of copper-based MOF has been described and in particular ([Cu3(btc)2(H2O)3]-H2O), directly deposited on ceramic foam. A characterisation of the samples obtained under different synthetic conditions through X ray analysis, thermogravimetric analysis, porosimetry and electron scanning microscopy (SEM) has been shown. Ultimately, the degree of MOF coating on the supports was assessed, and their ability to adsorb CO2 was examined through experimental trials that tested the capture process under precise temperature and pressure conditions using a 10 mol% mixture of air and CO2. A fixed bed system, structured with coated foams, exhibited a CO2 capture capability of 0.40 mmol/gMOF, minimal pressure drops, and low temperatures for reactivation, all critical requirements for industrial applications.

This work is part of a research project aimed at studying potential sorbents for CO2 capture. The main parameters characterising the adsorption process of zeolite 13X were derived with the aim of overcoming the limits of experimental analysis and thus predicting the performances of the materials of interest. In particular, the main parameters that control the adsorption process of CO2 in zeolite 13X were evaluated through parametric optimisation. This systematic procedure allows for the prediction of the performances of the materials at different operating conditions, identifying the most suitable ones for the case under consideration. Another important application lies in the possibility of a preliminary study of a potential process scale-up for future industrial use. The captured carbon dioxide can be stored or used as a reagent in the production of products with higher economic values, such as methanol, DME and others.

Carbon capture, utilization, and storage (CCUS) is one of the key promising technologies that can reduce GHG emissions from those industries that generate CO2 as part of their production processes. Compared to other effective CO2 capture methods, the adsorption technique offers the possibility of reducing the costs of the process by setting solid sorbent with a high capacity of adsorption and easy regeneration and, also, controlling the performance of gas-solid contactor. In this work, an amine-functionalized mesoporous sorbent was used to capture CO2 emissions in a confined-fluidized bed. The adoption of a confined environment allows the establishment of a homogeneous expansion regime for the sorbent and allows to improve the exchange of matter and heat between gas and solid phase. The results illustrate how the different concentration of the solution adopted during the functionalization affects the adsorption capacity. That, measured as mg of CO2 per g of sorbent, was determined by breakthrough curves from continuous adsorption tests using different concentrations of CO2 in air. Mesoporous silica functionalized with a concentration of 20% of APTES proves to be the best viable option in terms of cost and ease of preparation, low temperature of regeneration, and effective use for CO2 capture.

Porous ceramics are nowadays recognized to have the potential to be used for a wide variety of industrial applications. These span from filtration in metals foundry and casting to absorption, catalysts and catalyst supports to lightweight structural components. Thus, considerable research efforts are focused on innovative processing technologies resulting in better control of their structures and improvement of their properties. Ceramic foams are within these materials of great interest, especially for their application as filters for aluminum alloys and other nonferrous materials in foundry, in particular because of their resistance to high temperatures. However, shaping such kind of ceramic foams can result difficult and costly. This paper presents an explorative experimental campaign on the workability and characterization of various ceramic foams for the previous mentioned industrial application. grinding and drilling strategies have been applied in order to verify the possibility to effectively process the materials under investigation.

To reduce the anthropogenic CO2 emissions produced from fossil fuel burning plants, the application of carbon capture and storage (CCS) is necessary and development of a more efficient and economically feasible CO2 capture process is essential as an alternative to the conventional amine scrubbing process which uses aqueous amine solutions. CO2 capture can be enhanced by improving both the gas–solid contact efficiency and by tuning a specific high-performance sorbent. The aim of this research is to investigate the adsorption of CO2 using impregnated mesoporous silica in a “confined-fluidized bed”. This non-conventional fluidized bed (sometimes also termed the “packed-fluidized bed”) seems suitable for improving the efficiency of gas–solid processes for which the bypass effect of the gas–solid contact caused by bubbling represents a major drawback. Results, expressed as grams of CO2 adsorbed per kilogram of material, are discussed in terms of amine load in the sorbent, breakthrough time and fraction of bed utilized. The stability of the materials after regeneration cycles is also discussed. The results obtained confirm that the confinement of the bed allows exploiting fluidization technology in adsorption operations. The operating velocity can be fixed at a value at which the thermal effects also connected to the operation are kept under control.

CO2 adsorption is performed across a fluidized bed comprising a commercial pelletized 13X zeolite confined to the interstitial void network of a coarse glass sphere packed bed. Compared with traditional fixed bed adsorption, the packed fluidized system allows operation across a wide-range of gas velocities without a substantial increase in pressure drop. Additionally, with respect to conventional fluidization regimes, the technique adopted herein prevents the formation of bubbles in favour of enhancing the bed expansion ability. Furthermore, for a given mass of sorbent, the CO2 uptake capacity is observed to increase as a result of improved thermal conditions and in eliminating any by-pass effect at the gas-particle interface, which is associated to the suppression of bubbling. (C) 2019 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Previous research has shown that when a bed of particles is fluidized in a confined environment like that provided by the voids of a fixed bed of coarser spheres, bubble flow is totally suppressed in favour of an increased ability of the bed to expand homogeneously. A "confined fluidized bed" (sometimes also termed “packed-fluidized bed”) seems therefore likely to improve the efficiency of gas-solid processes for which the by-pass effect associated to bubbling represents a major drawback. To check these potentialities, the paper presents the results of an investigation on CO2 adsorption by a fluidized bed of pellets of 13X zeolite. The performances of a confined fluidized bed and that of a conventional system are compared in terms of moles of CO2 adsorbed per unit mass of sorbent, breakthrough time and fraction of bed utilized at the breakpoint. The results obtained demonstrate that confinement of the bed allows exploiting fluidization technology in adsorption operations whose thermal control also results easier. INTRODUCTION Among the several strategies proposed for containing CO2 emissions, such as reducing energy consumption, increasing the efficiency of energy conversion, switching to the use of renewable energy sources, the techniques of carbon capture and storage (CCS) offer a valid tool in the short to medium term (Bhown, A.S., Freeman, B.C. 2011). In the field of CCS the development of an innovative, efficient and cost-effective CO2 capture technique based on adsorption on solid sorbents, can be a promising alternative whose success may depend not only on the availability of highly specific materials tailored at the molecular scale (Younas et al. 2016) but also on the improvement of the gas-solid contact efficiency (Raganati et al. 2014; R. Girimonte et al. 2016). Various materials, such as zeolites, metal organic frameworks (MOFs), activated carbon and amine-modified silica show high capacity of adsorption of CO2. Exploiting advantages of fluidization technology such as high mass transfer rates and low pressure drop without suffering too low adsorption efficiencies requires the adsorption process to be run in the regime of particulate fluidization, i.e. in the absence of bubbly flow. Adsorption can be carried out in systems often referred to as “packed fluidized beds” or “confined fluidized beds” (Girimonte and Vivacqua, 2013), i.e. beds of particles fluidized in the voids of a packing of coarser solids, usually spheres. This technique has been raising an increasing interest as its fluid-solid contact mode is particularly suitable for operations in which maximization of the conversion of a gaseous reactant is crucial. Such a goal can be reached thanks to the ability of these fluidized systems to prevent the formation of bubbles, a route through which part of the gas flow rate by-passes the contact with the solid phase, whether it is another reactant or a catalyst. Some zeolites commercially available as spheres of relative large size obtained by pelletizing the original powder are sorbents suitable for being used in a confined system like that employed in this investigation. This paper illustrates how the adsorption performance of a commercial Zeolite 13X improves when the operation is conducted in a confined fluidized bed. Effectiveness of CO2 capture has been assessed in terms of moles of CO2 adsorbed per unit mass of adsorbent solid, breakthrough time and fraction of bed utilized at the breakpoint and a comparison is made with the results obtainable in a packed-bed and in a conventional fluidized bed.

The paper presents the results of an investigation into CO2 adsorption by a fluidized bed of pellets of 13X zeolite. The experiments compare the performance of a confined and that of a conventional fluidized bed using the same apparatus at ambient temperature and pressure. The effect of CO2 concentration in the inlet air stream, superficial gas velocity and particle size of the fluidized sorbent is analysed with reference to gas streams in Which the fraction of carbon anhydride is that typical of a flue gas. The effectiveness of CO2 adsorption is assessed in terms of moles of CO2 adsorbed per unit mass of sorbent, breakthrough time and fraction of bed utilized at the breakpoint. Along with the increase of the adsorbed mass of CO2, it is found that the increment of the brealcthtough time is roughly equal to 70%, while the increase of the fraction of bed utilized is always about 30%. Furthermore, in the confined fluidized bed the increase of temperature associated to adsorption is more limited and can be controlled by regulating the superficial gas velocity.The results obtained demonstrate that confined fluidization improves the efficiency of the adsorption process thus constituting a valid alternative to the conventional technique. (C) 2017 Elsevier B.V. All rights reserved.

In the present study, the use of surfactant-free mesoporous TiO2 combined with an antioxidant and photo-protecting agent, such as ferulic acid (FA), as a sunscreen was investigated for the first time.

SBA-15 type mesoporous silica has been modified to produce a covalent bond with β-cyclodextrin by two different synthetic approaches to obtain an hybrid system able to work as a drug delivery system for progesterone. In the first approach, SBA-15 silica was first let to react with 3-glycidyloxypropyltrimethoxysilane to produce an epoxide ring functional group on mesoporous silica. The latter was then reacted under basic conditions with mono-6-deoxy-6-mercapto-β-cyclodextrin (β-CDCH2SH), prepared in its turn in two steps from β-cyclodextrin (β-CD) through monotosylation to give β-CDCH2OTs followed by thiolation with thiourea. In the second approach, a silica suitably functionalized with a terminal thiol group (obtained by the reaction of SBA-15 silica with 3-mercaptopropyltrimethoxysilane) was reacted with β-CDCH2OTs. The obtained materials were characterized by X-Ray powder diffraction, nitrogen adsorption, 13C Cross Polarization Magic Angle Spin Nuclear Magnetic Resonance (13C CP/MAS NMR). Progesterone was loaded on the materials producing complete filling of mesopores and cyclodextrin cavities. Its release was studied at different pH values. Only one of the two progesterone-loaded delivery device is able to retain the drug in the system during the first period at acid pH (2 h) and release it after pH increase.

We present in this communication that phenyl phosphonic acid can be efficiently loaded in mesoporous SBA-15 and aminopropyl-modified SBA powdered samples through the incipient wetness impregnation method. High amount of phosphonic acid can be reach up to 380mg/g of sample. We use multinuclear solid state NMR as a method of choice for the indeep characterization of the samples. Thus we demonstrate that phosphonic acid molecules do not crystallize inside the pores. The molecules are highly mobile in SBA-15 because they are submitted to a confinement effect due to the mesoscopic size of the pores and consequently they exhibit a weak interaction with the silica walls. In the case of aminopropyl-modified SBA material, we show that the molecules are rigid and that they are in strong interaction with the aminopropyl groups. Moreover, a 2D double quantum 1H NMR experiment recorded at high field and high spinning speed permit to propose a model of the phosphonate-aminopropyl interaction. The increase in spectral resolution due to the combination of high magnetic field and fast MAS rate allows also the assignment of 1H resonances in aminopropyl-modified SBA matrix and notably allows the assignment of the protons resonance of the amino group.

Ordered mesoporous molecular sieves are widely studied as alternative materials in areas where sorptive and catalytic applications are required. MCM-41 type mesoporous material was tested as sorbent of 2-methylbenzoic acid (MBA), an aromatic carboxylic acid selected as model molecule for adsorption studies on mesoporous silicas. Adsorption kinetic studies of MBA on MCM-41 type materials were carried out using ethanol solutions at different MBA concentrations. Experimental results followed Langmuir isotherm model showing large adsorption capacity (3.5 g/g). Two kinetic models, the pseudo first- and second-order, were selected to describe the adsorption process and to determine the best model fitting with the experimental data. Kinetic parameters for each kinetic equation were calculated and discussed. It was shown that the MBA adsorption process onto MCM-41 material could be described by the pseudo-second-order equation and that the MCM-41 performs as a suitable adsorbent material.

The in situ preparation of a Cu-bearing metal-organic framework material, HKUST-1, coated on an open-cell ceramic foam (CF) is presented. The material used as coating is a robust metal-organic framework with a micro-porous structure that is a reminiscent of the zeolite framework topology. In spite of relatively low thermal stability of HKUST-1 with respect to zeolites, this material has an interesting catalytic behavior in the formation of hydroxyl radicals. The synthesized HKUST-1 coated on CF (HKUST-1/CF) samples has been characterized and then used to carry out the preliminary hydroxyl radicals formation from hydrogen peroxide (HP) decomposition and the consecutive phenol oxidation tests. The maximum phenol abatement obtained is 95% after about 40min, using a solution with an HP conversion of 70%. The HP kinetic data analysis has been done varying the reaction temperature in the range 60–80°C. The hierarchical micro/macro-porous catalytic system has been used for more than 40 consecutive reaction runs, maintaining the catalytic activity and showing a negligible copper leaching.