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Evaluation of fluorinated derivatives od styrene oxide as substrates of halohydrin dehalogenase
No full textFluorirani aromatski spojevi su važni kiralni građevni blokovi u farmaceutskoj industriji. Jedna od metoda njihove sinteze je i biokatalitički put korištenjem enzima halogenhidrin-dehalogenaze (HHDH). U ovom radu proučavana je reakcija otvaranja epoksidnog prstena, fluoriranog derivata stiren oksida uz azid kao nukleofil. Reakcija je katalizirana s HHDH iz divljeg soja mikroorganizma poznata i pod nazivom HheC. Provedene su preliminarne reakcije u vodenom mediju s 5 % organskog otapala. U njima je evaluirano šest različitih epoksida s atomima fluora kao supstituentima na stiren oksidu. Metodom početnih brzina određeni su kinetički modeli i parametri za svaku od reakcija. Utjecaj koncentracije epoksida (cepox) na brzinu enzimske reakcije odgovara Michaelis-Meteničinoj enzimskoj kinetici, dok utjecaj koncentracije azida odgovara kinetičkom modelu s inhibicijom supstrata. Enzimsku kinetiku u vodenom mediju bilo je moguće mjeriti samo do koncentracije epoksida od 20 mM, zbog njihove ograničene topljivosti. Kako bi se povećala topljivost epoksida, reakcije je potrebno provoditi pri većim udjelima organskog otapala. Usporedbom procijenjenih kinetičkih parametara i pregledom literature određeno je da položaj supstituenta ima presudnu ulogu na aktivnost enzima i afinitet supstrata prema enzimu. Od ispitivanih stiren oksida najbolji supstrat za HheC je onaj koji ima najudaljenije supstituente od epoksidnog prstena, odnosno u para položaju.Fluorinated aromatic compounds are important chiral building blocks in the pharmaceutical industry. One of the methods for their synthesis is a biocatalytic path with enzyme halohydrin dehalogenase (HHDH). In this work, the ring-opening reaction of epoxides was studied. Substrates were fluorinated derivates of styrene oxide with azide as a nucleophile. The reaction was catalyzed by wild-type HHDH, also known as HheC. Preliminary reactions were ran in a buffered medium with 5 % of organic solvent. Six different epoxides with fluorine atom on different positions of the phenyl ring were evaluated. By using the initial reaction rate method, kinetic models and parameters for each reaction were determinend. The influence of the concentration of epoxides (cepox) on the rate of enzymatic reactions fits Michaelis-Menten kinetics, while the influence of azide concentration fits the Michaelis-Menten kinetics with substrate inhibition. Because of low epoxide solubility, enzymatic kinetic in the water medium can be determined up to the epoxide concentration of 20 mM. To increase epoxide solubility reactions need to be carried out at higher concentration of organic solvent. By comparing the estimated kinetic parameters and literature search, it was found that the substituent position has a deterministic role in enzyme activity and affinity of the substrate towards the enzyme. From the tested styrene oxides, the best substrate for HheC is the one that has substituents on the opposite side from the epoxide ring
Activity of halohydrin dehalogenase in the presence of organic solvents
No full textU ovome radu ispitana je aktivnost enzima halogenhidrin-dehalogenaze u prisustvu organskih otapala različitih koncentracija. Aktivnosti enzima su praćene preko produkta p-nitrofenilstiren oksida koji je dobiven pretvorbom iz 1-(p-nitrofenil)-2-bromoetanola uz halogenhidrin-dehalogenazu kao katalizator. Proučavane su relativne aktivnosti enzima budući specifične dosta odstupaju jedna od druge. Na temelju dobivenih podataka, određena je aktivnost enzima u prisustvu pojedinog organskog otapala. Aktivnost enzima opada s porastom koncentracije organskog otapala. Porastom koncentracije organskog otapala, enzimi i dalje zadržavaju aktivnost, ali ne na razini aktivnosti u vodenom mediju. U prisustvu n-heksana, cikloheksana i toluena, enzimi zadržavaju vrlo visoku aktivnost čak i u čistom organskom otapalu.This research was focused on the activity of halohydrin dehalogenase enzyme in different concentrations of organic solvents. The assays were monitored via the p-nitrophenylstyrene oxide product obtained by conversion from 1-(p-nitrophenyl)-2-bromoethanol with halohydrin dehalogenase as catalyst. Relative activities of enzymes were evaluated and compared, since the specific ones deviate a lot from each other. Based on the obtained data, the activity of the enzyme in a particular organic solvent was determined. As concentration of organic solvent increases, enzyme activity decreases. As the concentration of the organic solvent increases, the enzymes remain active, but at lower level than in an aqueous solution. In the presence of n-hexane, cyclohexane and toluene, the enzymes retain their activity even in pure organic solvents
Synthesis of mesoporous Zr-doped CeO2 via hard template method
No full textS porastom potrebe za djelotvornim i oporabljivim rješenjima za uspješno vođenje različitih kemijskih reakcija znanstveno-istraživački radovi usmjereni su ka pronalasku djelotvornih i ekološki prihvatljivih katalizatora, nosača djelatnih tvari, adsorbensa za vlagu i stakleničke plinove. U ovome je radu opisana sinteza i karakterizacija jednog takvog potencijalnog katalizatora: cerijeva(IV) oksida dopiranog cirkonijem. Uzorci su pripremljeni metodom nanolijevanja pomoću krutog predloška na mezoporoznoj siliki, čija je sinteza također sastavni dio ovoga rada. Nanostrukturirani materijali, naročito porozni keramički materijali, pokazuju se kao izvrsni adsorbensi, katalizatori te nosači djelatnih tvari u farmaceuticima zbog svoje iznimno velike specifične površine, što utječe na visok broj aktivnih mjesta na površini tih materijala. Pripravljeni su uzorci okarakterizirani raznim karakterizacijskim tehnikama te su u ovome radu izneseni rezultati ispitivanja i prokomentirana svojstva mezoporoznih nanostrukturiranih keramičkih materijala.Following the rising need for efficient and recyclable solutions for the successful management of a variety of chemical reactions scientific efforts are directed towards finding efficient and ecologically acceptable catalysts, carriers of active substances, humidity and greenhouse gas adsorbents. The synthesis and characterization of one such potential catalyst is described in this paper: zirconium doped cerium(IV) oxide. The samples have been prepared using the method of nanocasting with formerly synthesised mesoporous silica serving as a hard template. Nanostructured materials, especially porous ceramics, have shown themselves to be excellent adsorbents, catalysts and active substance carriers in pharmaceutics because of their significantly large specific surface area, which results in a vast number of active points on the surface of these materials. Synthesised samples have been characterized by various characterization techniques and the results of them, as well as the properties of mesoporous nanostructured ceramics are described in this paper
Biodegradation of microplastics by fungi
No full textU današnje vrijeme sve više se koristi plastika u svakodnevnom životu, a odbačena plastika predstavlja prijetnju okolišu. Degradacijom plastike u okolišu nastaju sitne čestice plastike, koje se nazivaju mikroplastika. Za razgradnju mikroplastike potrebno je nekoliko desetljeća. Procesi recikliranja i spaljivanja ne predstavljaju održiva rješenja za zbrinjavanje plastičnog otpada, stoga je potreban razvoj novih tehnologija za upravljanje otpadom. U usporedbi s drugim procesima razgradnje, biorazgradnja se smatra učinkovitim procesom razgradnje mikroplastike. Proces biorazgradnje je ekološki prihvatljiv i ekonomski isplativ. Biorazgradnja sintetičkih polimera je vrlo spor proces koji uključuje djelovanje okolišnih čimbenika i mikrobnih vrsta. Pri biorazgradnji mikroplastike, mikroorganizmi poput gljiva imaju važnu ulogu, oni izlučuju enzime, kao što su peroksidaza i lakaza, koji dodatno pospješuju razgradnju. Poznato je nekoliko rodova gljiva, koje imaju sposobnost biorazgradnje mikroplastike, a to su: Aspergiluss, Penicillium, Fusarium, itd. Prema nekim istraživanjima razgradnja mikroplastike je učinkovitija kada su fotodegradacijski i termodegradacijski procesi uključeni istovremeno u proces biorazgradnje. U ovom radu dati će se pregledni dio o vrstama plastike, fizikalno-kemijskim i biološkim procesima biorazgradnje mikroplastike.Nowadays, more and more plastic is used in everyday life, and discarded plastic poses a threat to the environment. When plastic decomposes in the environment, it produces small plastic particles called microplastics. It takes several decades for microplastics to break down. Recycling and incineration are not sustainable solutions for managing plastic waste, so the development of new waste management and remediation technologies is needed. Compared to other degradation processes, biodegradation is effective and best method for degrading plastics because it does not cause pollution and is cost effective. Biodegradation of synthetic plastics is a very slow process in which environmental factors and the action of microbial species also play a role. Fungi play an important role in the biodegradation of microplastics as they secrete degradative enzymes such as peroxidases and laccases that can cause effective degradation. Some known species that show effective degradation of microplastics are Aspergillus, Pencillium, Fusarium, etc. Some studies state that the degradation of plastics was more effective when photodegradation and oxidative mechanisms were simultaneously involved in biodegradation. This study will provide an overview of the types of plastics and the abiotic and biotic processes of microplastic biodegradation
Photoreduction by intense pulsed light
No full textNanotehnologija i nanomaterijali predstavljaju prekretnicu u modernoj znanosti. Njihovom primjenom postiže se neizmjeran tehnološki napredak. Zbog izvrsnih svojstava posebnu ulogu imaju nanomaterijali poput nanosrebra i grafena. Međutim, postupci njihove proizvodnje mogu biti vrlo komplicirani te izuzetno skupi. Cilj ovog rada je dobiti grafen i nanosrebro postupkom fotoredukcije. U tu svrhu korištena je intenzivna pulsirajuća svjetlost (Intense pulsed light, IPL) pomoću koje je provedena redukcija srebrova klorida i grafen oksida. Kao rezultat su dobivene nanočestice srebra te reducirani grafen oksid dispergiran u različitim sustavima kao što su voda, etanol, N,N-dimetilacetamid (DMAc), citratni pufer pH vrijednosti 10 te etanol uz dodatak polivinil butirala (PVB) kao stabilizatora. Zbog svoje jednostavnosti, brzine, ekološke prihvatljivosti i niske potrošnje energije fotoredukcija intenzivnom pulsirajućom svjetlosti je sve češće primjenjivana metoda dobivanja nanomaterijala. Učinkovitost redukcije praćena je UV/Vis spektrofotometrom, a rezultati su prikazani grafički. Reduciranost grafen oksida se očituje pomakom maksimuma apsorpcije sa vrijednosti od oko 230 nm do oko 260 nm. Analizom rezultata može se zaključiti da se fotonska redukcija grafen oksida može uspješno provesti u različitim disperznim sredstvima. Također, uspješno je provedena fotoredukcija srebrovog klorida, a prisutnost nanosrebra potvrđena je pojavom maksimuma apsorbancije pri valnoj duljini od 420 nm.Nanotechnology and nanomaterials represent a turning point in modern science. Their application leads to immense technological progress. Due to their excellent properties, nanomaterials such as nanosilver and graphene play a special role. However, their production processes can be very complicated and extremely expensive. The goal of this thesis is to obtain graphene and nanosilver by photoreduction. For this purpose, intense pulsed light (IPL) was used to reduce silver chloride and graphene oxide. As a result, silver nanoparticles and reduced graphene oxide were obtained dispersed in different solvents such as water, ethanol, N,N-dimethylacetamide (DMAc), citrate buffer with a pH value of 10, and ethanol with the addition of polyvinyl butyral (PVB) as a stabilizer. Due to its simplicity, promptitude, environmental suitability and low energy consumption, photoreduction with intense pulsed light is increasingly used as a production method of nanomaterials. The reduction efficiency was monitored with a UV/Vis spectrophotometer, and the results were presented graphically. The reduction of graphene oxide is manifested by the shift of the absorption maximum from a value of approximately 230 nm to 260 nm. Analyzing the results, it can be concluded that the photoreduction of graphene oxide can be successfully carried out in different dispersants. Also, the photoreduction of silver chloride was successfully performed, and the presence of nanosilver was confirmed by the appearance of an absorbance maximum at a wavelength of 420 nm
Production and characterization of functional filament based on PE-LD/TIO2 and PE-LD/TIO2/CNT composites
No full textAditivna proizvodnja (engl. additive manufacturing) čini jedan dio proizvodnog strojarstva kojemu je krajnji cilj izrada predmeta nanošenjem čestica u tankim slojevima. Kako bi dobili konačni proizvod, potrebno je konstruirati trodimenzionalni model računalnim programima za modeliranje ili digitalizirati već postojeći objekt. Cilj ovog rada bio je uspješno proizvesti funkcionalni filament promjera 1,75 mm koji će se moći koristiti za izradu dijelova reaktora za fotokatalitičku razgradnju onečišćivala. Smjesa za ekstrudiranje pripremljena je metodom suhog miješanja (engl. dry blending) tako što su granule polietilena niske gustoće (PE-LD) pomiješane s titanijevim dioksidom (TiO2) te ugljikovim nanocjevima (CNT) u raznim omjerima. Dobivenu smjesu prethodno je potrebno ekstrudirati na dvopužnom ekstruderu, zatim slijedi usitnjavanje te ekstrudiranje na jednopužnom ekstruderu. Dodan je CNT do 0,25 %, a TiO2 do 15 % masenog udjela. Karakterizacija dobivenog filamenta provedena je diferencijalnom pretražnom kalorimetrijom (DSC), termogravimetrijskom metodom (TGA) i vlačnim testom. Epruveta za kidalicu dizajnirana je u programu za računalno potpomognuti dizajn (CAD) te je nakon dizajniranja ispisana 3D-pisačem. Završno, optimirani su uvjeti 3D-ispisa na temelju najuspješnijeg ispisa epruvete koja je bila pogodna za kidalicu. Kao rezultat uspješno su proizvedene tri epruvete od svakog uzorka kompozita i tri epruvete uzorka od čistog PE-LD-a. Diferencijalnom pretražnom kalorimetrijom nije uočen pravilan trend promjene tališta dodatkom punila. Termogravimetrijskom analizom ustanovljeno je da stvarni maseni udio punila u uzorku nije jednak onom umiješanom, te da se dodatkom punila povećava potrebna temperatura za početak razgradnje mase uzorka. Rezultati dobiveni vlačnim testom ispitivanjem na kidalici nemaju pravilan trend promjene rastezne čvrstoće dodatkom punila.Additive manufacturing is one part of manufacturing engineering, the goal is to produce objects by applying particles in thin layers. In order to obtain the final product, it is necessary to construct a three-dimensional model with computer modeling programs or digitize an existing object. The goal of this work was to successfully produce a functional filament with a diameter of 1.75 mm that can be used to make reactor parts for the photocatalytic degradation of pollutants. The extruding mixture was prepared using the dry blending method by mixing low density polyethylene granules (PE-LD) with titanium dioxide (TiO2) and carbon nanotubes (CNT) in various proportions. The resulting mixture must first be extruded on a twin-screw extruder, followed by shredding and extrusion on a single-screw extruder. CNT was added up to 0,25 %, and TiO2 up to 15 % by mass. The obtained filament was characterized by differential scanning calorimetry (DSC), thermogravimetric method (TGA) and tensile test. The sample for the universal testing machine was designed in a computer-aided design (CAD) program and after design it was printed with a 3D-printer. Finally, the 3D-printing conditions were optimized based on the most successful printing of the sample that was suitable for the universal testing machine. As a result, three samples of each composite and three samples of pure PE-LD were successfully produced. Differential scanning calorimetry did not observe a proper trend of melting point change with the addition of fillers. By thermogravimetric analysis, it was established that the actual mass fraction of the filler in the sample is not equal to that mixed in, and that the addition of the filler increases the necessary temperature for the start of decomposition of the sample mass. The results obtained by the tensile test by testing on the universal testing machine do not show a trend of change in tensile strength with the addition of fillers
Investigation of interaction between pharmaceuticals and microplastic particles
No full textRast ljudske populacije iz godine u godinu uzrokuje povećanje upotrebe farmaceutika u svakodnevnom životu, što izrazito nepovoljno djeluje na okoliš, prije svega onaj vodeni, uzrokujući njegovo onečišćenje. Osim upotrebe farmaceutika, povećava se i upotreba plastike, koja je sveprisutna u našim životima. Degradacijom plastike nastaje mikroplastika koja posjeduje veliku specifičnu površinu na koju se vežu onečišćujuće tvari u okolišu. Interakcija onečišćujućih tvari sa mikroplastikom može povečati njezin toksični učinak na okoliš i zdravlje ljudi. Cilj ovoga rada je ispitati adsorpciju farmaceutika karbamazepina (CBZ) na čestice mikroplastike pripremljene iz nestarenih uzoraka poli(etilen-tereftalata) (PET 0) i uzoraka podvrgnutih ubrzanom starenju pod UV zračenjem tijekom 56 dana (PET 56) te njihov štetni učinak na vodeni okoliš. Prije određivanja toksičnosti mikroplastike na koju je adsorbiran farmaceutik, bitno je odrediti toksičnost pojedinih komponenti. Njihov štetni učinak procijenjen je provedbom standardnih testova akutne toksičnosti na zelene mikroalge Pseudokirchneriella subcapitata (ISO 8692). Rezultati su pokazali da se UV starenjem povećava udio manjih frakcija čestica mikroplastike, što ukazuje na povećavanje amorfne faze, struktura postaje manje uređena, gube se mehanička svojstva, odnosno smanjuju se tvrdoća i krutost polimera. Rezultati adsorpcije karbmazepina odgovaraju Freundlichovom modelu što ukazuje na adsorpciju u više slojeva. Adsorpcija je najizraženija pri nižoj temperaturi, u kombinaciji sa PET 0, što upućuje na fizisorpciju. U slučaju ispitivanja toksičnosti nestareni materijal pokazao je veću toksičnost u odnosu na materijal staren 56 dana pod UV zračenjem, a najveću toksičnost pokazala je kombinacija CBZ + CaCl2 + PET 0, dok su pojedinačne komponente pokazale manji toksični učinak.The growth of the human population from year to year causes an increase in the use of pharmaceuticals in everyday life, which has an extremely unfavorable effect on the environment, primarily the water environment, causing its pollution. In addition to the use of pharmaceuticals, the use of plastic, which is ubiquitous in our lives, is also increasing. Degradation of plastic creates microplastics, which have a large specific surface to which pollutants in the environment bind. The interaction of pollutants with microplastics can increase its toxic effect on the environment and human health. The aim of this work is to investigate the adsorption of the pharmaceutical carbamazepine (CBZ) on microplastic particles prepared from unaged poly(ethylene terephthalate) (PET 0) particles and samples subjected to accelerated aging under UV radiation for 56 days (PET 56) and their adverse effect on the aquatic environment. Before determining the toxicity of microplastics on which a pharmaceutical is adsorbed, it is important to determine the toxicity of individual components. Their harmful effect was evaluated by performing standard acute toxicity tests on the green microalgae Pseudokirchneriella subcapitata (ISO 8692). The results showed that UV aging increases the proportion of smaller fractions of microplastic particles, which indicates an increase in the amorphous phase, the structure becomes less ordered, the mechanical properties are lost, thus the hardness and stiffness of the polymer decrease. The results of carbamazepine adsorption correspond to the Freundlich model, which indicates adsorption in multiple layers. Adsorption is most pronounced at lower temperature, in combination with PET 0, which indicates physisorption. In the case of toxic evaluation, the pristine material showed higher toxicity compared to the material aged for 56 days under UV radiation, and the combination of CBZ + CaCl2 + PET 0 showed the highest toxicity, while the individual components showed a lower toxic effect
Procjena utjecaja vodene matrice na razgradnju farmaceutika i određivanje mehanizma razgradnje
No full textAccording to the 3rd EU Watch List under the Water Framework Directive, a list of substances was suggested as good candidates for the next watchlist. In this study two pharmaceuticals from this list were chosen, Carbamazepine (CBZ) and Ibuprofen (IBP), two important and widely used recalcitrant pharmaceuticals found in water. The aim of this study is to evaluate the influence of several water matrix factors on the degradation of CBZ and IBP, with three different advanced oxidation processes (AOPs). To the best of our knowledge so far, there has been no research comparing UV-C, ultrasound (US) and microwave (MW) based processes under different operational parameters (oxidant dosage, pH, humic acid, nitrite ion, nitrate ion, chloride ion, phosphate ion and sulfate ion). Each of these factors depend on the degradation process had synergistic or inhibitory effect on degradation rate of studied pharmaceuticals. The used Taguchi method had great and significant results and indicated the effect of studied factors on degradation processes that, in most cases, were in agreement with previous literature findings, as well as required fewer experiments, time, and costs. Water matrix constituents had a significant impact on the degradation efficiency. Furthermore, the biodegradability of CBZ and IBP and degradation products of CBZ through UV-C based processes were investigated.Prema 3. popisu prioritetnih tvari prema Okvirnoj direktivi o vodama EU, popis tvari koje treba pratiti predložen je kao dobar kandidat za sljedeći popis prioritetnih tvari. U ovom radu odabrana su dva farmaceutika s ovog popisa, karbamazepin (CBZ) i ibuprofen (IBP), dva važna i široko korištena rekalcitratna farmaceutika pronađena u vodi. Cilj ovog istraživanja je procijeniti utjecaj nekoliko čimbenika vodene matrice na razgradnju CBZ i IBP, s tri različita napredna oksidacijska procesa (AOP). Koliko nam je poznato, do sada nije bilo istraživanja koja bi uspoređivala procese temeljene na UV-C, ultrazvuku (US) i mikrovalovima (MW) pod različitim radnim parametrima (doza oksidansa, pH, huminska kiselina, nitritni ion, nitratni ion, klorid ion, fosfatni ion i sulfatni ion). Svaki od ovih čimbenika, ovisno o procesu razgradnje, imao je sinergistički ili inhibitorni učinak na brzinu razgradnje ispitivanih farmaceutika. Korištena Taguchi metoda dala je izvrsne i značajne rezultate te je ukazala na utjecaj proučavanih čimbenika na procese razgradnje koji su u većini slučajeva bili u skladu s dosadašnjim literaturnim nalazima, te su zahtijevali manje eksperimenata, vremena i troškova. Sastojci vodene matrice imali su značajan utjecaj na učinkovitost razgradnje. Nadalje, ispitana je biorazgradivost CBZ-a i IBP-a i produkti razgradnje CBZ-a putem UV-C procesa
Investigating the rheological properties of cosmetic products
No full textZbog snažnog razvoja kozmetičke industrije i potrebe za konstantnim inovacijama i poboljšanjima proizvoda potrebno je pronaći što prihvatljivija rješenja. Da bi to bilo moguće potrebno je poznavati reološka svojstva kozmetičkih proizvoda i modele po kojima se ponašaju. Ako je to poznato, onda su poznati i parametri određenih modela te kako se na njih može utjecati da bi se dobili proizvodi željenih fizikalnih i kemijskih svojstava. Za dobivanje željenih svojstava koriste se polimeri, odnosno modifikatori reološkog ponašanja koji mogu biti prirodni i sintetski. Sintetski polimeri su umjetni te se dobivaju spajanjem postojećih monomera, dok se prirodni mogu dobiti iz biljaka, životinja ili mikroorganizama. Upotrebljavaju se za zgušnjavanje te poboljšavaju strukturu i teksturu proizvoda i omogućavaju duži rok trajanja. U ovom radu ispitan je utjecaj karbomera na reološko ponašanje pripremljenih proizvoda. Karbomeri su klasa polimera koji služe kao reološki modifikatori jer u vodenim otopinama povećavaju viskoznost, pomažu stvaranju gelova i stvaraju emulzije.Due to the strong development of the cosmetics industry and the need for constant innovation and product improvements, it is necessary to find the most acceptable solutions. In order for this to be possible, it is necessary to know the rheological properties of cosmetic products and the models by which they behave. If this is known, then the parameters of certain models are also known and how they can be influenced to obtain products with the desired physical and chemical properties. To obtain the desired properties, polymers are used, i.e. modifiers of rheological behavior, which can be natural or synthetic. Synthetic polymers are artificial and are obtained by combining existing monomers, while they can be obtained naturally from plants, animals or microorganisms. They are used as thickeners and improve the structure and texture of the product and enable a longer shelf life. In this paper, the emphasis is on carbomer. Carbomers are a class of polymers that serve as rheological modifiers because in aqueous solutions they increase viscosity, help form gels and form emulsions
Development of monolithic catalysts for catalytic oxidation of aromatic volatile organic compounds using 3D-printing technology
No full textU ovom doktorskom radu ispitana je mogućnost primjene komercijalne fotoosjetljive smole Ceramic resin za izradu keramičkih monolitnih nosača katalizatora stereolitografijom kao jednom od tehnika aditivne proizvodnje. Specifični ciljevi uključivali su 3D-ispis monolitnih nosača različitih geometrija, razvoj i primjenu odgovarajuće tehnike nanošenja katalitički aktivnog sloja (miješani oksidi Mn, Cu, Fe i Ni) na pripremljene monolitne nosače, uključujući i različite izvedbe statičkih miješalica kao potencijalnih nosača aktivnih komponenata i testiranje njihove učinkovitosti za oksidaciju smjese aromatskih hlapljivih organskih spojeva (benzen, toluen, etilbenzen i o-ksilen - BTEX) kao i pojedinačnih modelnih BTEX komponenti. Ukupno je izrađeno 12 različitih funkcionalnih izvedbi 3D-ispisanih monolitnih nosača katalizatora, od čega 5 izvedbi u obliku statičkih miješalica. Detaljno je ispitan utjecaj različitih parametara pripreme na fizičko-kemijske, toplinske, mehaničke i katalitičke značajke različitih izvedbi strukturiranih katalizatora te utjecaj procesnih uvjeta na brzinu oksidacije aromatskih hlapljivih organskih spojeva. Rendgenskom difrakcijskom analizom utvrđeno je da se keramička faza kompozitne smole Ceramic resin sastoji od SiO2, tj. da nakon toplinske obrade dolazi do formiranja kristobalita, minerala koji je jedna od temperaturno ovisnih polimorfnih modifikacija kvarca. Elementarni sastav dodatno je potvrđen EDX analizom pri čemu je dobiveno izvrsno slaganje s literaturnim vrijednostima za istu smolu. Određena je veličina keramičkih čestica u smoli uporabom metode laserske difrakcije. Rezultati analize pokazali su da se veličina keramičkih čestica kreće u rasponu od 0,5 μm do 414 μm. Vrijednost medijana veličine čestica (d50) u populaciji iznosi 34,8 μm. Dominantna veličina keramičkih čestica u populaciji (dmode) iznosi 44,7 μm, dok Sauterov promjer (d3,2) čestica iznosi 91,5 μm. Toplinska svojstva smole Ceramic resin ispitana su provedbom simultane TGA/DTA analize. Provedeno je ispitivanje dimenzijske stabilnosti kako bi se eksperimentalno odredili korekcijski dimenzijski faktori koje treba uzeti u obzir prilikom 3D-ispisa monolitnih nosača katalizatora da bi nakon toplinske obrade ostvarili željene dimenzije. Na svim izrađenim monolitnim nosačima katalizatora izmjeren je pad tlaka u reaktorskom sustavu. Rezultati ispitivanja pokazali su gotovo zanemariv pad tlaka pri radnim uvjetima korištenim u provedenom istraživanju. Uvid u morfologiju 3D-ispisanih nosača s i bez nanesenog katalitičkog sloja i određivanje debljine nanesenog katalitičkog sloja dobiveno je upotrebom pretražne elektronske mikroskopije. Sastav katalitički najaktivnijih miješanih manganovih oksida (MnFeOx i MnCuOx) potvrđen je Ramanovom spektroskopijom. Na temelju usporedbe s rezultatima dobivenih rendgenskom difrakcijskom analizom i rendgenskom fotoelektronskom spektroskopijom uspješno je definiran sastav prisutnih miješanih metalnih oksida. Katalitički sloj nanesen je primjenom tehnike mokre impregnacije i sol-gel tehnike. Rezultati ispitivanja adhezije katalitičkog sloja na monolitnim nosačima pokazali su izvrsne rezultate s manje od 2 % gubitka mase nakon pola sata izlaganja djelovanju ultrazvuka radne frekvencije 37 kHz. Na temelju mjerenja katalitičke aktivnosti pripremljenih monolitnih katalizatora zaključeno je da je impregnacija prikladnija tehnika. Također je provedeno optimiranje kemijskog sastava katalitičkog sloja s obzirom na očekivane konverzije modelnih komponenti. Najučinkovitijom geometrijom 3D-ispisanih monolitnih nosača katalizatora pokazala se geometrija nosača ZS (zvijezda sa stijenkom) koja je sadržavala dodatne strukturne elemente (pera) s vanjske strane stijenke. 3D-ispisani monolitni nosač ZDP (zvijezda s dodatnim perima) imao je najveću geometrijsku površinu (28 cm^2) i najveću masu katalitičkog sloja (12,4 mg) te je pokazivao čak i nešto veću katalitičku aktivnost u usporedbi s aktivnošću komercijalnog (kordijeritnog) monolitnog nosača slične geometrijske površine (29 cm^2) na koji je nanesen isti katalitički sloj. Rezultati testiranja katalitičke aktivnosti pokazali su da se sve četiri BTEX komponente uklanjaju iz reakcijske smjese već pri temperaturi od 179 °C, što je od velike ekonomske važnosti s obzirom na njihovu primjenu u realnim sustavima. U završnom dijelu istraživanja provedena je analiza i modeliranje monolitnog reaktora. Za tu svrhu predložen je jednodimenzijski (1D) heterogeni model reaktora, koji uključuje kinetički model za reakciju prvog reda. Provedena je usporedba rezultata dobivenih primjenom BTEX smjese i pojedinačnih BTEX spojeva. Ocjena prihvatljivosti predloženog modela koja je provedena na temelju pripadajućih vrijednosti korijena standardnog odstupanja između eksperimentalno dobivenih i teorijski predviđenih vrijednosti pokazala je da predloženi model uspješno opisuje eksperimentalne rezultate. S obzirom na činjenicu da je 1D heterogeni model izveden na temelju pripadajućih bilanci za modelne komponente u plinskoj fazi i bilanci za modelne komponente na površini katalitičkog sloja, što odgovara fizičkoj slici procesa, zaključeno je da je predloženi model prikladan za opisivanje katalitičke oksidacije BTEX i srodnih aromatskih hlapljivih organskih spojeva uz primjenu heterogenih strukturiranih katalizatora. Rezultati prikazani u ovom doktorskom radu ukazuju na izuzetan potencijal i velike mogućnosti primjene tehnologije aditivne proizvodnje pri proizvodnji složenih izvedbi katalizatora i kemijskih reaktora. Potvrđeno je da se tehnikom stereolitografije mogu uspješno pripremiti keramički monolitni nosači koji su prema svojim katalitičkim značajkama i primjenskim svojstvima usporedivi s katalizatorima izrađenim od komercijalne kordijeritne keramike, pri čemu posebno treba istaknuti njihovu veću fleksibilnost s obzirom na proizvodnju složenih geometrijskih oblika.This dissertation investigated the possibility of using the commercially available photosensitive resin Ceramic resin for the fabrication of ceramic monolithic catalyst carriers by using stereolithography as one of the additive manufacturing techniques. Specific objectives included 3D-printing of monolithic carriers with different geometries, developing and applying a suitable technique for depositing a catalytically active layer (mixed oxides of Mn, Cu, Fe, and Ni) on the prepared monolithic carriers, including different designs of static mixers as potential active component carriers, and testing their effectiveness for oxidation of a mixture of aromatic volatile organic compounds (BTEX) and individual model components. A total of 12 different functional variants of 3D-printed monolithic catalyst carriers were prepared, 5 of which were in the form of static mixers. The influence of different preparation parameters on the physicochemical, thermal, mechanical and catalytic properties of different designs of structured catalysts and the influence of process conditions on the oxidation rate of aromatic volatile organic compounds were studied in detail. X-ray diffraction analysis showed that the ceramic phase of the ceramic resin composite was composed of SiO2, i.e., cristobalite, a mineral that is a temperature-dependent polymorphic modification of quartz, was formed after heat treatment. The elemental composition was confirmed by EDX analysis, where excellent agreement was obtained with literature values for the same resin. The size of the ceramic particles in the resin used was determined by the laser diffraction method. The results of the analysis showed that the size of the ceramic particles ranged from 0.5 μm to 414 μm. The median value of the particle size (d50) in the population is 34.8 μm. The predominant size of the ceramic particles in the population (dmode) is 44.7 μm, while the Sauter diameter (d3,2) of the particles is 91.5 μm. The thermal properties of the ceramic resin were investigated by simultaneous TGA / DTA analysis. Dimensional stability tests were performed to experimentally determine the dimensional correction factors that must be considered in 3D-printing of monolithic catalyst carriers to obtain the desired dimensions after heat treatment. The pressure drop in the reactor system was measured with all fabricated monolithic catalyst carriers. The test results showed almost negligible pressure drop under the operating conditions used in the study. Scanning electron microscopy was used to gain insight into the morphology of the 3D-printed carriers with and without an applied catalytic layer and to determine the thickness of the applied catalytic layer. The composition of the most catalytically active manganese mixed oxides (MnFeOx and MnCuOx) was confirmed by Raman spectroscopy. Comparison with the results of X-ray diffraction analysis and X-ray photoelectron spectroscopy successfully determined the composition of the mixed metal oxides present. The catalyst layer was applied by the wet impregnation technique and the sol-gel technique. The results of the study of the adhesion of the catalytic layer to monolithic carriers showed excellent results with less than 2 % weight loss after half an hour of exposure to ultrasound at an operating frequency of 37 kHz. From the measurements of catalytic activity of the prepared monolithic catalysts, it was concluded that impregnation is a more suitable method. The chemical composition of the catalyst bed was also optimized with respect to the expected conversions of the model components. The most efficient geometry of the 3D-printed monolithic catalyst carriers was found to be the geometry of the ZS carrier, which contained additional structural elements on the outside of the wall. The 3D-printed monolithic ZDP carrier had the largest geometric surface area (28 cm^2), the largest catalytic bed mass (12.4 mg), and exhibited even slightly higher catalytic activity in comparison with a commercial (cordierite) monolithic carrier with similar geometric surface area (29 cm^2) that was coated with the same catalytic layer. The results of the catalytic activity tests showed that all four BTEX components are removed from the reaction mixture already at a temperature of 179 °C, which is of great economic importance considering their application in real systems. In the last part of the research, the analysis and modeling of a monolithic reactor was carried out. For this purpose, a one-dimensional (1D) heterogeneous reactor model was proposed, which includes a kinetic model for the first-order reaction. A comparison of the results obtained with a BTEX mixture and single BTEX compounds was performed. The evaluation of the acceptability of the proposed model, performed on the basis of the corresponding root values of the standard deviation between the experimentally obtained and the theoretically predicted values showed that the proposed model successfully described the experimental results. Based on the fact that the heterogeneous 1D model is derived based on the corresponding balances for the model components in the gas phase and the balance for the model components on the surface of the catalytic layer, which corresponds to the physical picture of the process, it was concluded that the proposed model is suitable for describing the catalytic oxidation of BTEX and related aromatic volatile organic compounds using heterogeneously structured catalysts. The results presented in this dissertation demonstrate the extraordinary potential and great possibilities of the application of additive manufacturing technology in the fabrication of complex designs of catalysts and chemical reactors. It was confirmed that the stereolithography technique can successfully fabricate ceramic monolithic carriers comparable in catalytic properties and application characteristics to catalysts made of commercially available cordierite ceramics, with particular emphasis on their greater flexibility in the fabrication of complex geometric shapes