Tesi di Dottorato

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End date: 2023Subject: search.filters.subject.Ingegneria chimica

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    Modelling study of vanadium based alloys and crystalline porous materials for gas separation membranes
    (2016-02-26) Borisova Evtimova, Jenny; De Luca, Giorgio; Curcio, Efrem; Molinari, Raffaele
    Gas! membrane! separation! is! an! attractive! technology! that! is! often! superior! to! other! more! conventional! procedures! for! separation! of! gaseous! species! in! terms! of! energy! consumption! and! environmental! impact.! A! key! factor! for! membrane! separations! is! the! membrane! itself! with! its! properties,! which! determine! the! overall! performance! of! the! process.! One! essential! membrane! characteristic!is!the!transport!selectivity.!High!separation!factors!are!especially!difficult!to!achieve! for! mixtures! of! light! gases! having! comparable! kinetic! diameters.! Moreover,! high! permeability,! correspondingly! high! solubility! and! diffusivity! in! dense!membranes,! are! crucial! aspects! for! the! performance! and! further! practical! application! of!membrane! devices.! In! this! frame,! the!material! used!as!a!selective!layer!is!determinant.!Therefore,!scientists!devote!immense!efforts!to!the!search! of! optimal! gasBsorbent! combinations,! including! thorough! study! of! existing! structures! and! elaboration!of!new!ones!with!sieving!properties.!The!large!effort!and!time!required!for!preparation! and!experimental!testing!of!materials!impede!the!advancement!of!new!membranes.! In!this!study,!we!propose!procedures!based!on!computational!calculations!and!theoretical!models! that! can!be!used! to!predict! the!behaviour!of! some!of! the!membrane!materials!of! interest! for! gas! separation! applications.! In! particular,! we! focus! on:! i)! bodyBcentred! cubic! VNiTi! alloys! as! novel! materials!for!H2Bselective!dense!membranes!and!ii)!crystalline!porous!materials!that!are!attractive! media!for!separation!of!light!gases!such!as!H2,!O2,!CO,!CO2,!CH4!and!N2.!These!two!types!of!materials! are! treated! using! different! methodologies,! adapted! to! the! needs! of! our! research! objectives! associated!to!each!material.! In!the!case!of!dense!metal!membranes,!the!long!standingBcontroversy!over!occupancy!of!interstitial! hydrogen! in! VBbased! alloys! is! addressed.! The! VBNiBTi! system! is! of! particular! interest! here,! exhibiting!high!H2!permeability!and!improved!mechanical!properties!relative!to!pure!V.!This!work! intends!to!gain!understanding!of!hydrogenBmetal!interactions!as!function!of!alloy!composition!and! thereby!to!optimize!these!new!materials!and!advance!their!development!as!novel!membranes!for! H2! separation.!We! use! a! firstBprinciples! approach! that! gives! insights! into! the! sites! preference! of! hydrogen! and! assesses! the! role! of! Ti! and! Ni! substitutional! solutes! for! the! hydrogen! absorption! affinity.! The!method! based! on!Density! Functional! Theory! requires! no! experimental! input! except! crystal!structure!information.!Furthermore,!it!uses!no!empirical!or!fitting!parameters!in!contrast!to! other!computational!techniques.!Hence!this!approach!provides!an!alternative!way!to!explore!new! metal!alloys!for!H2!separation!membranes.!The!applied!methodology!can!be!used!further!in!highB throughput!calculations!to!screen!various! alloy!compositions.!The!heretoBreported!results!will!be! used!as!guidance!for!tailoring!the!formulation!of!VNiTi!solid!solutions!and!preparation!of!low!cost†! dense!alloy!membranes!in!the!frame!of!other!projects!(e.g.!European!DEMCAMER!project).! Further,! we! explore! how! singleBcomponent! inputs! can! be! used! to! forecast! the! ideal! selectivity! towards! light! gases! of! crystalline! porous!materials,! used! for!membrane! preparation.! Theoretical! models! for! describing! gas! separation! properties! of! zeotype! materials! as! function! of! structural! characteristics!and!operation!conditions!are!proposed.!The!model!parameters!can!be!obtained!as! experimentally!as!well!as!computationally.!To!analyse!the!extent!of!validity!and!limitations!of!the! models,!ideal!selectivities!of!few!crystalline!porous!materials!are!evaluated,!including!widely!used! zeolites!(NaA,!CaA)!and!a!metal!organic!framework!structure!(ZIFB8).!The!results!verified!that!the! theoretical!expressions!could!be!used!for!screening!series!of!zeotype!materials!when!reliable!single! gas!adsorption!data!are!available.!However,!since!the!models!don’t!take!into!account!all!parameters! (namely! related! to! the! membrane! design)! and! mechanisms! involved! in! gas! transport! through! porous!membranes,!their!predictions!should!be!considered!as!values!referring!to!an!ideal!case.!
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    Chemical looping desulphurization: model and applications to power systems
    (2016-02-26) Settino, Jessica; Molinari, Raffaele; Amelio, Mario
    I processi di assorbimento, sia sici che chimici a base di ammine, sono attualmente utilizzati per rimuovere e cacemente i composti dello zolfo. Nonostante l'eccellente desolforazione, questa strategia e termicamente ine ciente, in quanto richiede gas a bassa temperatura. Scopo di questo lavoro e quello di analizzare soluzioni alternative che operino a temperature pi u elevate. A tale scopo, e stato analizzato il processo del chemical looping. Si tratta di una nuova tecnologia, in cui un materiale sorbente, in contatto con il gas combustibile grezzo, viene convertito nel suo solfuro e poi rigenerato cos da ricominciare il ciclo. Il sistema e costituito da due reattori: uno per la rigenerazione e l'altro per la desolforazione. Un modello matematico di tale sistema e stato sviluppato con il software Athena Visual Studio ed i suoi risultati confrontati con quelli ottenuti dal modello proposto dal National Energy Technology Laboratory, validati sulla base di dati sperimentali. Nella fase successiva, il sistema modellato e stato applicato a tre casi studio di interesse industriale: per la produzione di energia elettrica negli impianti a ciclo combinato con gassi cazione integrata, nei processi di metanazione, nei processi per la sintesi del metanolo. Mediante simulazioni, condotte con i software commerciali Thermo ex e UniSim Design, sono stati studiati gli e etti della desolforazione a caldo sulle prestazioni dei diversi sistemi.
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    Modeling of mixing and drying processes in pasta production
    (2014-11-30) Carnevale, Ilaria; de Cindio, Bruno; Baldino, Noemi
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    Processi di separazione, estrazione e bioconversione nella produzione di biocombustibili da micro alghe
    (2014-10-28) Lopresto, Catia Giovanna; Pagnotta, Leonardo; Arcuri, Natale; Calabrò, Vincenza
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    Membrane emulsification for the development of particulate systems for drug encapsulation
    (2014-11-11) Imbrogno, Alessandra; Giorno, Lidietta; Drioli, Enrico; Molinari, Raffaele
    Il micro-incapsulamento è una tecnica ampiamente utilizzata per incapsulare sostanze nutraceutiche, farmaci, proteine, cellule ecc. Oggigiorno, la ricerca nel campo farmaceutico viene sempre più indirizzata allo sviluppo di forme farmaceutiche a rilascio modificato (ad esempio emulsioni multiple, sfere e capsule mono/ polinucleate) in grado di migliorare la biodisponibilità di principi attivi scarsamente solubili. La maggior parte delle metodologie utilizzate per la preparazione di particelle micro e nano-strutturate prevedono un processo iniziale di emulsificazione. In questo caso, il controllo della dimensione e dell’uniformità delle gocce è di fondamentale importanza per produrre particelle solide di dimensione controllata, da cui dipende la via di somministrazione, la distribuzione nei tessuti e l’interazione con le cellule. Negli ultimi 25 anni, enormi progressi sono stati realizzati nella preparazione di emulsioni con una dimensione controllata delle gocce grazie a un sempre più vasto utilizzo dell’emulsificazione a membrana, un processo vantaggioso rispetto alle tecniche convenzionali in termini di semplicità operativa, basso consumo energetico, alta riproducibilità e facile scale-up. L’aspetto innovativo di questo processo è la produzione delle gocce di emulsione singolarmente, ottenuta mediante permeazione della fase dispersa attraverso i pori della membrana, mentre il distacco della goccia avviene all’uscita del poro per effetto di uno sforzo di taglio esercitato dal fluire della fase continua. Un grande potenziale dell’emulsificazione a membrana per la preparazione di formulazioni farmaceutiche è la possibilità di combinare le proprietà chimiche della formulazione con le proprietà strutturali della particella (quali dimensione e dispersione) in modo da realizzare prodotti con caratteristiche funzionali idonee a specifiche applicazioni. Nella realizzazione di sistemi micro e nano-strutturati per l’incapsulamento di molecole bioattive, le proprietà chimico-fisiche del materiale sono anche di fondamentale importanza. Tra i materiali organici, i polimeri biodegradabili (in particolare il poli-caprolattone e il copolimero dell’acido lattico e glicolico) sono quelli di maggiore impiego in quanto offrono la possibilità di realizzare particelle che, una volta introdotte nell’organismo, vengono degradate in sottoprodotti metabolizzati dalle cellule. Questa proprietà conferisce a questi materiali un’eccellente biocompatibilità e il rilascio del farmaco incapsulato nelle particelle può essere modulato dalla velocità di degradazione del polimero. Inoltre questi polimeri sono idrofobi e quindi ideali per l’incapsulamento di farmaci insolubili in acqua, una procedura necessaria per poter essere somministrati nella circolazione sanguigna. Nonostante questi polimeri siano ampiamente utilizzati per la preparazione di sistemi micro e nano-strutturati, numerose problematiche sono state riscontrate nel controllo della dimensione e dispersione delle particelle e la loro morfologia. Lo scopo del presente lavoro di tesi è quello di utilizzare l’emulsificazione a membrana per la preparazione di sistemi micro e nano-strutturati utilizzabili per l’incapsulamento di farmaci idrofili e lipofili e realizzati con i polimeri biodegradabili precedentemente menzionati. Dall’analisi dello stato dell’arte sono stati individuati una serie di requisiti importanti per la preparazione di sistemi particellari: i) produrre particelle con dimensione e dispersione controllata utilizzando un processo ad alta produttività; ii) mantenere un basso stress meccanico per preservare l’attività delle sostanze incapsulate; iii) utilizzare un processo che può essere applicato su larga scala a livello industriale. La produzione di particelle altamente uniformi e con dimensione controllata mediante l’utilizzo dell’emulsificazione a membrana è già stato pienamente riportato in letteratura. Tuttavia, la possibilità di poter ottenere una produzione controllata dell’emulsione mantenendo allo stesso tempo un’alta produttività e un basso stress meccanico nell’impianto è tutt’ora oggetto di studio. Sulla base di queste osservazioni, gli avanzamenti proposti dal presente lavoro di tesi sono: • migliorare la produttività e l’efficienza del processo di emulsificazione a membrana mediante: i) l’utilizzo di una membrana con bagnabilità asimmetrica lungo la sezione al fine di mantenere allo stesso tempo una produzione controllata dell’emulsione ad un alto flusso di fase dispersa; ii) l’utilizzo di membrane di tipo “setaccio” in acciaio inox in modo da combinare i vantaggi delle caratteristiche strutturali della membrana setaccio (bassa porosità, basso spessore, pori rettilinei e uniformemente distribuiti) con l'elevata resistenza chimica dell’acciaio inossidabile, che è meno soggetto allo “sporcamento” per interazione con i componenti dell’emulsione; • indagare, inizialmente su piccola scala e poi con processi adatti per la produzione su larga scala, la preparazione di sistemi micro e nano particellari combinando la emulsificazione a membrana con il processo di diffusione del solvente per ottenere un controllo della dimensione e morfologia delle particelle in modo preciso e riproducibile rispetto all’ evaporazione del solvente comunemente utilizzata; • investigare l’utilizzo di processi di emulsificazione a membrana recentemente introdotti per applicazioni su larga scala, quali emulsificazione a membrana con flusso pulsato e invertito della fase continua ed emulsificazione a membrana con movimento torsionale della membrana, per la produzione di particelle micro e nano-strutturate in condizioni di basso stress meccanico e alta produttività del processo.
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    Bio-Hybrid Membrane Process for Food-based Wastewater Valorisation: a pathway to an efficient integrated membrane process design
    (2014-11-11) Gebreyohannes, Abaynesh Yihdego; Giorno, Lidietta; Curcio, Efrem; Aimar, Pierre; Vankelecom, Ivo F.J.; Molinari, Raffaele
    The food industry is by far the largest potable water consuming industry that releases about 500 million m3 of wastewater per annum with very high organic loading. Simple treatment of this stream using conventional technologies often fails due to cost factors overriding their pollution abating capacity. Hence, recently the focus has been largely centered on valorization through combinatorial recovery of valuable components and reclaiming good quality water using integrated membrane process. Membrane processes practically cover all existing and needed unit operations that are used in wastewater treatment facilities. They often come with advantages like simplicity, modularity, process or product novelty, improved competitiveness, and environmental friendliness. Thus, the main focus of this PhD thesis is development of integrated membrane process comprising microfiltration (MF), forward osmosis (FO), ultrafiltration (UF) and nanofiltration (NF) for valorization of food based wastewater within the logic of zero liquid discharge. As a case study, vegetation wastewater coming from olive oil production was taken. Challenges associated with the treatment of vegetation wastewater are: absence of unique hydraulic or organic loadings, presence of biophenolic compounds, sever membrane fouling and periodic release of large volume of wastewater. Especially presence of biophenolic compounds makes the wastewater detrimental to the environment. However, recovering these phytotoxic compounds can also add economic benefit to the simple treatment since they have interesting bioactivities that can be exploited in the food, pharmaceutical and cosmetic industries. The first part of the experimental work gives special emphasis on the development of biohybrid membranes used to control membrane fouling during MF. Regardless of 99% TSS removal with rough filtration, continuous MF of vegetation wastewater using 0.4 μm polyethelene membrane over 24 h resulted in continuous flux decline. This is due to sever membrane fouling mainly caused by macromolecules like pectins. To overcome the problem of membrane fouling, biocatalytic membrane reactors with covalently immobilized pectinase were used to develop self-cleaning MF membrane. The biocatalytic membrane with pectinase on its surface gave a 50% higher flux compared to its counterpart inert membrane. This better performance was attributed to simultaneous in-situ degradation of foulants and removal of hydrolysis products from reaction site that overcome enzyme product inhibition. Although the biocatalytic membrane gave a better performance, its fate is disposal once the covalently immobilized enzyme gets deactivated or oversaturated with foulants. To surmount this problem a new class of superparamagnetic biochemical membrane reactor was developed, verified and optimized. This development is novel for its use of superparamagnetic nanoparticles both as support for the immobilized enzyme and as agent to render the membrane magnetized. This reversible immobilization method was designed to facilitate the removal of enzyme during membrane cleaning using an external magnet. Hence PVDF based organic-inorganic (O/I) hybrid membrane was prepared using superparamagnetic nanoparticles (NPSP) as inorganic filler. In parallel, superparamagnetic biocatalytic nanocomposites were prepared by covalently immobilizing pectinase on to the surface of NPSP dispersed in aqueous media. The synergetic magnetic responsiveness of both the O/I hybrid membrane and the biocatalytic particle to an external magnetic field was later on used to physically immobilize the biocatalytic particles on the membrane. This magnetically controlled dynamic layer of biocatalytic particles prevented direct membrane-foulant interaction, allowed in-situ degradation, easy magnetic recovery of the enzyme from the surface of the membrane, use of both membrane and immobilized enzyme over multiple cycles and possibility of fresh enzyme make up. The system gave stable performance over broad range of experimental condition: 0.01-3 mg/mL foulant concentration, 1-9 g per m2 of membrane area bionanocomposites, 5- 45 L/m2.h flux and different filtration temperatures. Under condition of mass transfer rate prevailing reaction rate, the system gave upto 75% reduction in filtration resistance. After optimization of the different operational parameters, it also revealed no visible loss in enzyme activity or overall system performance, when 0.3 mg/mL pectin solution was continuously filtered for over two weeks. In addition, the chemical cleaning stability of the O/I hybrid membrane was studied under accelerated ageing and accelerated fouling conditions. The ageing caused change in the physicochemical characteristics and enhanced fouling propensity of the membrane due to step-by-step degradation of the polymeric coating layer of used NPSP. But 400 ppm NaOCl solution at pH 12 was found compatible; henceforth it was used to clean the membrane. Second major limitation identified during the treatment of vegetation wastewater is presence of large volume of wastewater that comes in short period following the harvest of olive fruit. To alleviate this problem, FO was investigated to concentrate the wastewater. This process is believed to be less energy demanding, suppose that draw solution does need to be regenerated, and with low foul propensity. By operating at 3.7 molal MgCl2 draw solution and 6 cm/s crossflow velocity, single-step FO resulted in an average flux of 5.2 kg/m2.h. and 71% volume concentration factor with almost complete retention of all the pollutants. Moreover, the system gave a stable performance over ten days when operated continuously. After FO, both NF and UF were used to fractionate the recovered biophenols from the concentrate streams of FO. Compared to polymeric UF membrane, ceramic NF gave better flux of 27 kg/m2.h at 200 L/h feed flow rate and 7 bar TMP. Finally, when FO was used as a final polishing step to recover highly concentrated biophenols from permeate of the UF; it gave an average flux of 5 kg/m2.h and VCF of 64%. In conclusion, a great success has been made in tackling the two most important challenges of vegetation wastewater valorisation using the concept of biohybridization and FO. The bioinspired NPSP provides strong evidence that magnetically controlled enzyme immobilization have an immense potential in membrane fouling prevention and paves a potential breakthrough for continuous wastewater filtration. By setting bio-inspired NPSP biocatalytic membrane reactor at the heart, it is possible to successfully use integrated membrane process for continuous valorisation of food based wastewater. In addition to fouling prevention, they open a new horizon for applications in localized biocatalysis to intensify performance in industrial production, processing, environmental remediation or bio-energy generation.
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    Evaluation of thermal polarization and membrane characteristics for membrane distillation
    (2014-11-11) Alì, Aamer; Drioli, Enrico; Aimar, Pierre; Bouzek, Karel; Fila, Vlastimil; Molinari, Raffaele
    The current PhD work emphasizes on various aspects of membrane distillation for approaching zero liquid discharge in seawater desalination. In broader sense, two themes have been discussed in detail: (i) correlation between membrane features and their performance in MD (ii) understanding and control of thermal polarization in MD. Introduction and state-of-the-art studies of MD including progress in membrane development, understanding the transport phenomenon, recent developments in module fabrication, fouling and related phenomenon and innovative applications have been discussed in introductory part of the thesis. The effect of operating conditions and dope compositions on membrane characteristics and correlation between membrane features and their performance has been discussed in subsequent section. It has been established that membrane morphology plays a crucial role in performance of the membrane for real applications. Furthermore, it has been demonstrated that the effect of membrane morphology is different for direct contact and vacuum configurations. Theoretical and experimental aspects of thermal polarization in direct contact membrane distillation have also been investigated. Thermal polarization phenomenon in a flat sheet membrane has been studied by using a specifically designed cell. The effect of operating conditions and solution concentration on thermal polarization has been explored experimentally. It has been observed that increased solution concentration favors the thermal polarization due to resulting poor hydrodynamic at the membrane surface and increase in diffusion resistance to the water vapors migrating from bulk feed phase to the membrane surface. Some active and passive techniques to decrease thermal polarization and possible fouling in membrane distillation have also been discussed in the current study. Thermal polarization can be greatly reduced by inducing secondary flows in the fluid flowing inside the fiber. The induction of secondary flows in the current study has been realized by using the fibers twisted in helical and wavy configurations. Due to improvement of thermal polarization coefficient on up and downstream, the undulating fiber geometries provide high flux and superior performance ratio. Application of intermittent and pulsatile flow to control thermal polarization in MD has also been discussed. It has been inferred that these flows have positive impact on performance ratio and volume based enhancement factors without compromising on packing density of the system. The application of MD for treatment of produced water has also been studied. The effect of membrane features on their performance for the treatment of this complex solution has been discussed. The desirable membrane features for successful application of MD for such treatment have been distinguished. It has been inferred that MD possesses the capability to produce a distillate of excellent quality and is an interesting candidate to recover the minerals present in the produced water. The fouling tendency of the membranes with different characteristics towards different types of feed solutions has also been discussed in this study. It has been shown that the porosity enhanced through the introduction of macrovoids in non-solvent induced phase separation technique creates problems related with wetting and pore scaling during practical application of such membranes. The fouling related issues are less severe in the membranes with sponge like microstructure but the overall porosity of such membranes is relatively less. Thus it has been concluded that there should be an optimum between the high throughput and stable performance of the membranes synthesized through phase inversion techniques. Conclusions of the study and future perspectives have been discussed in the last section of the study.
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    Analysis of membrane reactor integration in hydrogen production process
    (2014-11-11) Mirabelli, Ilaria; Drioli, Enrico; Barbieri, Giuseppe; Molinari, Raffaele
    In the H2 production field, the membrane reactor (MR) technology is considered a promising and interesting technology. In this thesis work the integration in a small scale hydrogen generator of an MR, to carry out the water gas shift reaction (WGS), has been studied. In particular, the effect of MR integration from a systems perspective, i.e. specifically assessing the impact of MR on the whole process, has been investigated. A preliminary design of a pilot scale MR to produced 5 Nm3/h of H2 by reformate stream upgrading has been performed. A CO conversion of 95% and an hydrogen recovery yield of 90% have been fixed as minimum performance target of the WGS-MR. Depending on the system considered to promote the driving force for the permeation, three scenarios have been proposed: base, vacuum and sweep scenario. On the basis of results from a preliminary scenario screening, the required membrane area (ca. 0.179 m2), for vacuum and sweep scenarios, has been estimated by means of an MR modelling and simulation. The results obtained from the pilot scale have been used for the scale-up of the WGS-MR integrated in the 100 Nm3/h hydrogen production unit. The plant for the integrated process (reformer and WGS-MR) has been simulated by using the commercial simulation tool Aspen Plus®. The MR integration, actually, implies a re-design of the process downstream the WGS reactor. Since more than 90% of the produced H2 is directly recovered in the permeate stream, the PSA unit can be removed, leading to a more compact system. For the retentate stream post processing, the possibility to recover the CO2, by means of membrane gas separation technology has been proposed. The results for a two stages membrane separation unit confirmed the technological feasibility of the CO2 capture, achieving the CO2 purity target. Pursuing the logic of process intensification, the comparison with the reference technology (reformer, high temperature shift, PSA) showed as the WGS-MR integrated system results in a more “intensified” process since a higher H2 productivity, a smaller plant and an enhanced exploitation of raw materials are obtained. In addition, since the MR delivers a high-pressure CO2-rich stream, it provides an opportunity for small-scale CO2 capture and thus possible emission reduction. The possibility to extend the spectrum of MR application in reactions of industrial interest, where hydrogen is produced as by-product, has been also studied. In particular, as case study, the direct conversion of n-butane to isobutene has been analysed showing as, from a thermodynamic point of view, better performance (equilibrium conversion up to seven times higher than the one of a traditional reactor) can be obtained.
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    An insight on pharmaceutical crystallization process by using membrane technology: PVDF-based mixed matrix membranes and PP grafted membranes as new tools for controlling the supersaturation rate and the heterogeneous nucleation mechanism.
    (2014-11-11) Caridi, Antonella; Drioli, Enrico; Di Profio, Gianluca; Molinari, Raffaele
    Questo elaborato finale del progetto di dottorato tratta lo studio del processo di cristallizzazione a membrana finalizzato alla produzione di composti farmaceutici in forma cristallina. Lo studio ha come obiettivo quello di dare una visione globale del processo di cristallizzazione a membrana andando oltre lo stato dell􀍛a􀆌te, bensì p􀆌opo􀅶e􀅶do l􀍛i􀅵ple􀅵e􀅶tazione della tecnica di cristallizzazione a membrana di base. A tal proposito il progetto è stato sviluppato seguendo in due diverse direzioni: da una parte la tecnica di 􀄐􀆌istallizzazio􀅶e a 􀅵e􀅵􀄏􀆌a􀅶a di 􀄏ase ha 􀇀isto l􀍛appli􀄐azio􀅶e ad u􀅶o spe􀄐ifi􀄐o settore dell􀍛i􀅶dust􀆌ia fa􀆌􀅵a􀄐euti􀄐a, dall􀍛alt􀆌a pa􀆌te lo studio è p􀆌oseguito investigando i meccanismi di cristallizzazione indotti dalla stessa membrana e successivamente ha visto una vera e propria progettazione di membrane opportunamente pensate per la cristallizzazione. Du􀅶􀆋ue, il 􀇀alo􀆌e aggiu􀅶to di tale studio 􀄐o􀅶siste 􀅶ell􀍛a􀇀e􀆌e di􀅵ost􀆌ato la possibilità di ampliare il campo di applicazione del processo a membrana, di aver esteso la conoscenza di base dei meccanismi di nucleazione eterogenea sottesi dalla membrana e di aver progettato, prodotto e caratterizzato delle membrane con differenti materiali e strutture appositamente per essere testati nella tecnica di cristallizzazione. In dettaglio, il lavoro presenta uno studio iniziale sul processo di nucleazione eterogenea che parte da particelle libere in soluzione per poi continuare studiando il processo di nucleazione eterogenea sullle membrane stesse. U􀅶a se􀄐o􀅶da sezio􀅶e t􀆌atta l􀍛appli􀄐azio􀅶e del processo a membrana alla cocristallizzazione farmaceutica. Successivamente inizia la parte di disegno e realizzazione di membrane eterogenee sia dal punto di vista chimico che strutturale: membrane fabbricate con tecniche e materiali differenti e membrane commerciali che sono state opportunamente funzionalizzate. Infine il lavoro si conclude con i tests di cristallizzazione condotti su tali membrane.
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    Studio della strutturazione della fase oleosa di emulsioni W/O a base di olio d'oliva
    (2012-12-13) Facciolo, Deborah; de Cindio, Bruno