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Značajne količine raznovrsnih ostataka (odnosno lignocelulozne biomase) nastaju u poljoprivredi, prehrambenoj industriji i šumarstvu. Stoga je važno podići svijest o mogućnostima primjene takvih materijala koji se u današnje vrijeme ne bi trebali tretirati kao otpad, već se mogu koristiti kao obnovljive biotehnološke sirovine za proizvodnju kemikalija, drugih visokovrijednih proizvoda i biogoriva. Lignocelulozni materijal uglavnom sadrži celulozu, hemicelulozu i lignin. Predmet interesa ovog rada je lignocelulozni otpad iz poljoprivrede i prehrambene industrije kao mogući sirovinski temelj za napredak održive biotehnološke proizvodnje u Republici Hrvatskoj. Razmotrene su dostupne količine ovih lignoceluloznih sirovina, tipovi bioprocesa u kojima se one mogu koristiti, postupci predobrade koje je neophodno provesti prije provedbe samog bioprocesa te vrste biotehnoloških proizvoda koje je moguće dobiti., Significant amounts of various residues (i.e. lignocellulosic biomass) are generated in agriculture, food industry and forestry. Therefore, it is important to raise awareness about the possibilities of using such materials, which nowadays should not be treated as waste, but can be used as renewable biotechnological raw materials for the production of chemicals, other high-value products and biofuels. Lignocellulosic material consists mainly of cellulose, hemicellulose and lignin. The subject of interest of this paper is lignocellulosic waste from agriculture and the food industry as a possible raw material basis for the progress of sustainable biotechnological production in the Republic of Croatia. The available amounts of these lignocellulosic raw materials, the types of bioprocesses in which they can be used, the pretreatment procedures that need to be carried out before the implementation of the bioprocess itself, and the types of biotechnological products that can be obtained have been considered.

Istraživanja u okviru teze imaju za cilj dobijanje polimernih mreža kod kojih se regulacijom sirovinskog sastava i uslova sinteze mogu menjati svojstva siloksanskih materijala u skladu sa krajnjom primenom. Osnovni cilj istraživanja ove teze je razvoj novih postupaka sinteze hibridnih siloksanskih nanokompozita na osnovu različitih prekursora mreža. Takođe, ispitan je i uticaj različitih tipova funkcionalizacije površina nanopunila silicijum(IV) oksida (sa hidrofobnom i hidrofilnom površinom) na svojstva kompozitnih materijala za specifične namene. Nanokompoziti na osnovu polimernih mreža se uglavnom koriste u onim primenama gde tradicionalne polimerne mreže ne mogu da zadovolje potrebe koje se pred njih stavljaju. Zato je potrebno razviti postupak koji bi omogućio dobijanje materijala na osnovu polimernih mreža sa poboljšanim mehaničkim, elastičnim i toplotnim svojstvima. Motivacija je vođena potrebom razvoja novih kompozitnih materijala koji imaju jedinstvena mehanička, toplotna, termomehanička svojstva sa mogućnošću da pomognu u rešavanju problema okoline, kao što su problem sa prostorom, sa automobilima, u elektronici i infrastrukturi, i naravno, oni će biti veliki izazov u nauci materijala i industriji.Siloksanske mreže su dobijene od α, ω-divinil poli(dimetilsiloksana) i poli(metil-hidrogensiloksana) u odnosu 60/40; 50/50 i 40/60. Nanokompoziti su sintetisani dodavanjem različitih sadržaja nanopunila silicijum(IV) oksida (1, 2, 5, 10 i 20 mas.%). Za potvrdu pretpostavljenog mehanizma reakcije umrežavanja siloksana korišćena je FTIR spektroskopija. TEM analiza je korišćena za procenu topologije i potvrdila je dobru disperziju punila u polimernom matriksu. Dodavanje nanopunila poboljšava mehanička svojstva dobijenih materijala i povećanje vrednosti prekidne jačine za kompozite sa hidrofobnim silicijum(IV)oksidom je veće u poređenju sa kompozitima sa hidrofilnim punilima, što je očekivano zbog bolje kompatibilnosti hidrofobne matrice i hidrofobnih punila. Termogravimetrijska analiza korišćena je za analizu uticaja vrste funkcionalizacije silicijum(IV) oksida na termičku stabilnost siloksanskih elastomernihmaterijala. Kao što se i očekivalo, porast sadržaja nanopunila povećava termičku stabilnost dobijenih hibridnih materijala. Uticaj punila na temperature faznog prelaza siloksanskih materijala analiziran je diferencijalnom skenirajućom kalorimetrijom. Zbog slabije kompatibilnosti hidrofilnog punila i hidrofobne matrice primećeno je smanjenje vrednosti Tm, a najmanja vrednost temperature topljenja primećena je za uzorak sa najvećim udelom hidrofilnog punila.Uticaj nanopunila na mehaničke i termičke karakteristike dobijenih materijala biće detaljno analiziran, pri čemu je potvrđeno poboljšanje mehaničkih svojstava siloksanskih elastomera dodatkom nanopunila. U cilju razvoja novih biokompatibilnih materijala i poboljšanja svojstava biorazgradivosti siloksanskih materijala biće sintetisani ABA blok kopolimeri koji se sastoje od segmenata poli(dimetilsiloksana) i poli(laktida). Kao makroinicijator za sintezu blok kopolimera korišćen je polidimetilisiloksan, pa je polimerizacija laktida inicirana hidroksilnim grupama siloksana. Poli(laktid) se odlikuje veoma dobrim mehaničkim svojstvima i biorazgradivošću, dok se kopolimerizacijom sa siloksanima utiče na mehanička svojstva kao i na svojstva površine sintetisanog kopolimera., Research in the thesis aims to obtain polymeric networks in which the regulation of the rawmaterial composition and the conditions of the synthesis can alter the properties of the siliconematerials in accordance with the final application. The main goal of the research of this thesis isthe development of new procedures for the synthesis of hybrid silicone nanocomposites based ondifferent precursors. The influence of different types of surface functionalisation of nanofillers(with hydrophobic and hydrophilic functionalised surface) on the properties of compositematerials for specific purposes was investigated. Nanocomposites based on polymer networks aremainly used in those applications where traditional polymer networks cannot meet the needs thatare expected. It is therefore necessary to develop a process that would enable the production ofmaterials based on polymeric networks with improved mechanical, elastic and thermal properties.Motivation is driven by the need to develop new composite materials that have uniquemechanical, thermal, thermo-mechanical properties with the ability to help solve environmental problems, such as space problems, cars, electronics and infrastructure, and of course they will bea challenge in the material science and industry. Siloxane networks were prepared from α,ω-divinyl poly(dimethylsiloxane) and poli(methyl-hydrogen siloxane) with a ratio 60/40; 50/50 and40/60. Nanocomposites were synthesised with the addition of different contents of silicananofiller (1, 2 5, 10 and 20 wt%). For the confirmation of the presumed mechanism of siloxanecrosslinking reaction FTIR spectroscopy was used. TEM analysis was used for topologyevaluation and confirmed good dispersion of the fillers into the polymer matrix. Addition ofnanofillers increased the mechanical properties of obtained materials and greater increase of thetensile strength for the composites based on hydrophobic silicon(IV)-oxide was assessed,compared with the hydrophilic ones. It was expected due to better compatibility of hydrophobicsilicone matrix and hydrophobic filler particles. Thermogravimetric analysis was used for theevaluation of the influence of the types of silicon(IV)oxide functionalisation, on the thermaldegradation of elastomeric materials. As it was expected the increases of nanofillers contentincreased the thermal stability of obtained hybrid materials. The influence of fillers on the phasetransition temperatures of siloxanematerials was analysed with the differential scanningcalorimetry. Due to the lower compatibility of hydrophilic filler and hydrophobic matrixdecreasing of Tm values was observed, and the lowest value of melting temperature was noticedfor the sample with the highest loading of hydrophilic filler.In order to develop new biocompatible materials and improve the biodegradability properties ofsilicone materials, ABA types of block copolymers consisting of segments ofpoly(dimethylsiloxane) and poly(lactide) was synthesized. As a macroinitiator for the synthesis ofthe block copolymer, poly(dimethylisiloxane) was used, so the lactide polymerization starts fromthe hydroxyl groups of siloxanes. Poly(lactide) is characterized by poor mechanical propertiesand biodegradability, while copolymerization with silicones will affect the mechanical andsurface properties of the synthesized copolymer.

Proizvodnja biogoriva iz obnovljivih sirovina privukla je pažnju znanstvenika jer može poslužiti za opskrbu energijom i alternativnim gorivima. Bioetanol je jedno od najzanimljivijih biogoriva zbog njegovog pozitivnog utjecaja na okoliš. Najčešće se proizvodi iz sirovina koje sadržavaju šećer i škrob. Međutim, razni izvori lignocelulozne biomase, kao što su poljoprivredni i šumski ostaci te zeljasti energetski usjevi, također mogu poslužiti kao sirovine za proizvodnju bioetanola, energije, topline i kemikalija s dodanom vrijednošću. Lignoceluloza je složena mješavina ugljikohidrata, koju treba učinkovito prethodno obraditi da bi se oslobodili biotransformacijski putevi u kojima enzimi proizvode fermentabilne šećere što nakon hidrolize fermentiraju u etanol. Unatoč tehničkim i ekonomskim poteškoćama, obnovljive lignocelulozne sirovine imaju nisku cijenu te ne utječu na hranu i prehrambeni lanac, čime potiču održivost. Za proizvodnju bioetanola iz obnovljivih sirovina razvijeni su različiti načini rada bioprocesora. Osim toga, intenzivno se razvijaju i alternativni postupci odvajanja i pročišćavanja bioetanola. Ovaj rad daje pregled novih trendova u proizvodnji bioetanola iz različitih obnovljivih sirovina, te postupaka njegovog odvajanja i pročišćavanja., Production of biofuels from renewable feedstocks has captured considerable scientific attention since they could be used to supply energy and alternative fuels. Bioethanol is one of the most interesting biofuels due to its positive impact on the environment. Currently, it is mostly produced from sugar- and starch-containing raw materials. However, various available types of lignocellulosic biomass such as agricultural and forestry residues, and herbaceous energy crops could serve as feedstocks for the production of bioethanol, energy, heat and value-added chemicals. Lignocellulose is a complex mixture of carbohydrates that needs an efficient pretreatment to make accessible pathways to enzymes for the production of fermentable sugars, which after hydrolysis are fermented into ethanol. Despite technical and economic difficulties, renewable lignocellulosic raw materials represent low-cost feedstocks that do not compete with the food and feed chain, thereby stimulating the sustainability. Different bioprocess operational modes were developed for bioethanol production from renewable raw materials. Furthermore, alternative bioethanol separation and purification processes have also been intensively developed. This paper deals with recent trends in the bioethanol production as a fuel from different renewable raw materials as well as with its separation and purification processes.

Cilj ovog diplomskog rada je istražiti primjenu viših alkohola (pentan-1-ola, oktan-1-ola, nonan-1-ola i oleil alkohola) kao ekstraktivnih otapala s visokim vrelištem za izdvajanje etanola iz fermentirane podloge u integriranom bioreaktorskom sustavu. Ekstrakcija etanola je istraživana u svrhu dobivanja ekološki, energetski i financijski učinkovitijeg procesa od uobičajeno primijenjene višestupanjske destilacije. Istraženo je toksično djelovanje ekstraktanta na kulturu kvasca Saccharomyces cerevisiae i ponašanje dvokomponentnih (ekstraktant–voda) odnosno trokomponentnih smjesa (ekstraktant-voda-etanol) te učinkovitost razdvajanja organske faze od podloge. Izrađeni su binodalni trokomponentni dijagrami za sustave pentan-1-ol/voda/etanol, oktan-1-ol/voda/etanol, nonan-1-ol/voda/etanol i oleil alkohol/voda/etanol. Na temelju binodalnih dijagrama izvršen je proračun potrebnih količina otapala za trostupanjski ekstrakcijski sustav i predložen je sustav tehnološke linije za izdvajanje etanola iz fermentirane podloge. The aim of this work was to investigate the application of higher alcohols characterized by high boiling points (i.e. pentan-1-ol, octan-1-ol, nonan-1-ol and oleyl alcohol) as extraction solvents for the ethanol extraction from broth, fermented in the integrated bioreactor system. The goal was the development of the ecologically, energetically and financially more efficient process than conventional multi-stage distillation. Applied extractants were tested for its toxicity on the Saccharomyces cerevisiae yeast culture. The behaviors of two-component systems (extractant-water) and three-component mixtures (extractant-water-ethanol) were investigated toward the efficiency of separation of organic phase (extract) and the water phase (rafinate). Binodal curves were constructed for systems: pentan-1-ol / water / ethanol, octan-1-ol / water / ethanol, nonan-1-ol / water / ethanol and oleyl alcohol / water / ethanol. Binodal diagrams were used for the calculations of required solvent amounts for the ethanol extraction in the three-stage extraction system. The plants for ethanol production based on extractions with higher alcohols were proposed.

Synthesis of lactic acid from petrochemicals has been cancelled and since 2011 the lactic acid has been exclusively produced by biotechnological processes - fermentation of glucose, sucrose or lactose by different microorganisms. Traditional use of the lactic acid and, nowadays, production of other chemicals and biodegradable polymers from the acid drive global lactic acid demand. Leading producers are investing in development of new bioprocesses for the lactic acid production from renewable raw materials by microorganisms which possess hydrolytic and fermentative activity. Main objective of investigation was development of new bioprocess that meets the European Union climate and energy goals - „20/20/20“ targets and the strategy „Innovating for Sustainable Growth: a Bioeconomy for Europe”. Application of novel highly efficient and sustainable bioprocess and construction of industrial plant for the lactic acid production depends on type of raw material to be used in market established manner in the European Union area. The new bioprocess of simultaneous saccharification of semi-solid substrate and fermentation to the lactic acid by amylolytic lactic acid bacterium was developed. The bacterium also possesses proteolytic activity and it can use proteins from the raw material as amino acid source. The developed bioprocess is suitable for scale up and it can be integrated in zero waste biorefineries in which other biochemical and biofuels can be produced from the renewable raw material.

S ciljem podupiranja intenzivnijeg korištenja relativno brzo obnovljivih izvora sirovine za primjenu u različitim industrijama te s općim stavom veće odgovornosti prema okolini i potrebom zaštite prirodnih resursa lan, konoplja, brnistra i vuna danas ponovo postaju važni u strategiji gospodarskog razvoja. Navedene sirovine se mogu ubrojiti među strateške tekstilne sirovine u Hrvatskoj, a obnavljanje njihove proizvodnje može rezultirati primjenom u tekstilnoj industriji (odjeća i/ili tehnički tekstil) ili drugih industrijama (prehrambena ili medicina).

Ethanol production (as a biofuel) from renewable raw materials is still more expensive than gasoline production from fossil oil. Therefore, integration of different technological stages into one single stage could result in a more cost-effective and energy saving bioprocess. In this research, intermediates of sugar beet processing were studied as a substrate for ethanol production in order to reduce ethanol price as a biofuel. For ethanol production from the raw sugar beet juice in the stirred tank bioreactor batch and fed batch cultivation techniques were used. In horizontal rotating tubular bioreactor (HRTB) batch ethanol production from raw sugar beet cossettes was studied by different initial inoculum quantity (9.1 - 23.1 v/m). In both cases, Saccharomyces cerevisiae was used as a production microorganism. During batch ethanol production from the raw sugar beet juice, bioprocess efficiency was 59.48 % and in the fed batch process 72.49 %, respectively. At the same time, ethanol production in the HRTB from the raw sugar beet cossettes with inoculum of 16.7 % v/m (raw sugar beet cossettes) resulted in the highest bioprocess efficiency of 79.92 %. On the basis of experimental data it is clear that both intermediates of sugar beet processing can be successfully used for ethanol production.

This paper gives an overview of the production and application of polymer materials based on renewable raw materials – biopolymers. It is pointed out that, investment of resources in the study of renewable raw materials in the last twenty years has led to the improvement of old and development of completely new chemical and biochemical processes for using biomass for the production of low molecular weight chemical substances, and especially for the production of biopolymers, which are biodegradable and compostable, and biopolymers which are nonbiodegradable. In the same period, producers of polymers based on fossil raw materials have also developed biopolymers that are biodegradable and some of them compostable and, most important, compatible with biopolymers based on renewable raw materials. The facts considering the state of biopolymers based on renewable raw materials on the market, and prediction of production increase over the next five years are also stated. Additionally, the main renewable raw materials and the biopolymers made from them that are already present in the world market are briefly listed. A short review of biopolymers based on cellulose from wood and annual plants is also given., U okviru ovoga rada dan je pregled stanja u proizvodnji i primjeni polimernih materijala na bazi obnovljivih sirovina - biopolimera. Ukazano je na to da su ulaganjem sredstava u izučavanje obnovljivih sirovina u posljednjih dvadesetak godina unaprijeđeni stari i razvijeni potpuno novi kemijski i biokemijski postupci uporabe biomase za dobivanje niskomolekulskih kemijskih supstancija, a posebno biopolimera koji su i biorazgradivi i kompostabilni, ali i biopolimera koji su bionerazgradivi. U istom razdoblju su i proizvođači polimera na bazi fosilnih sirovina razvili biopolimere koji su biorazgradivi, a neki i kompostabilni i što je vrlo bitno kompatibilni s biopolimerima na bazi obnovljivih sirovina. Navedeni su i podaci o stanju na tržištu biopolimera na bazi obnovljivih sirovina, kao i procjene povećanja proizvodnje u sljedećih desetak godina. Pored toga ukratko su prikazane osnovne obnovljive sirovine, kao i biopolimeri koji se od njih proizvode i već su prisutni na svjetskom tržištu. Dan je kratak prikaz biopolimera na bazi celuloze iz drveta i jednogodišnjih biljaka.

Ovaj rad je imao za cilj , razvoj postupka sinteze polimernih prekursora mreža na baziobnovljivih sirovina. Razvijen je postupak sinteze poli laktida u rastvoru dihlor metana. Vreme trajanja postupka sinteze je 6 h, a uspešnost samog procesa je potvrđena metodama identifikacije i karakterizacije dobijenih polimera PLLA. U ovom radu, za ispitivanja dobijenih polimernih materijala, uzimajući u obzir ideju o krajnjoj nameni, korišćene su sledeće metode: GPC ( Gel Permeation Chromarography) za određivanje raspodele molekulske mase; IR spektrofotometrija, prikazuje vibraciju atomskih, molekulskih ili funkcionaknih grupa; i termička analiza TGA i DSC, za praćenje promena pri kontrolisanom zagrevanju i hlađenju.Jedan od ciljeva rada je bio i da se da pregled postojećih teorija ojačanja elastomera punilima sa nano česticama, i ispita ponašanje nano-kompozitnih materiajala pod dejstvom visoko energetskog zračenja ( gama zračenja). U eksperimentalnom delu ispitivani su elastomerni materijale na bazi butadienakrilonitrilnog kaučuka (NBR) i hlorsulfonovanog polietilenskog kaučuka (CSM) . Mešanjem CSM i NBR formiraju se umreženi sistemi, koji se koriste kao prekursori mreža za dobijanje nano-kompozitnih materijala ojačanaih česticama aktivnih punilačađi i silicijum (IV) oksida. Kod tako dobijenih materijala ispitivane su karakteristike pre i posle ozračivanja γ zracima. Dinamičko-mehaničkom analizom potvrđen je ojačavajući efekat punila., This work was aimed at the development procedure for the synthesis of polymer precursors network based on renewable raw materials. Developed a procedure for synthesis of poly lactide in solution, dichloro methane. The duration of the synthesis procedure was 6 h, and the success of the process was confirmed by the methods of identification and characterization of the obtained polymer PLLA. In this paper, the investigation obtained polymer materials, taking into account the idea of final destination, following methods were used: GPC (gel permeation Chromarography) to determine the distribution of molecular weight, IR spectrophotometry, showing the vibration of atomic, molecular or funkcionaknih group, and thermal analysis TGA and DSC, to track changes in a controlled heating and cooling. One of the aims of this study was to be given to review of existing theories of reinforcement fillers elastomer with nano particles, and examine the behavior of nano-composite materiajala under the influence of high energy radiation (gamma radiation). In the experimental part of elastomeric materials have been studied on the basis of butadienakrilonitrilnog rubber (NBR) and chlorosulphonated polyethylene rubber (CSM). CSM NBR mixing and forming the network system, which are used as precursors for a network of nano-composite particles ojačanaih active fillers-carbon black and silicon (IV) oxide. With so obtained materials were investigated characteristics before and after irradiation with γ rays. Dynamic-mechanical analysis confirmed the reinforcing effect of fillers.

Industrijska proizvodnja mliječne kiseline podrazumijeva dvostupanjske procese kod kojih se u prvom stupnju polimerni ugljikohidrat hidrolizira do fermentabilnih ugljikohidrata, dok se u drugom stupnju jednostavniji ugljikohidrati u hranjivoj podlozi kompleksnog sastava fermentiraju do mliječne kiseline. Drugi stupanj je mikrobni proces tijekom kojeg se proizvodi jedan ili oba stereoizomera mliječne kiseline. Učinkovitost ovih bioprocesa može se povećati ukoliko se umjesto različitih pročišćenih sastojaka, koji se dodaju u hranjivu podlogu, koriste obnovljive sirovine. Takve bioprocese proizvodnje mliječne kiseline, kod kojih je reducirana količina opreme, kemikalija i energije potrebne za proizvodnju proizvoda s dodanom vrijednošću, provode mikroorganizmi koji iskazuju hidrolitičko- fermentativni aktivnost. Učinkovitost opisanih mikrobnih procesa može se povećati objedinjavanjem procesa u kojima se iz polimernih supstrata direktno proizvodi mliječna kiselina, postupaka izdvajanja i pročišćavanja mliječne kiseline i sustava za proizvodnju biorazgradljivih polimera i ko-polimera mliječne kiseline u tzv. integrirane bioprocese („od prirodnih polimera do biorazgradljivih polimera“).

Konvencionalne ofsetne boje, a posebno heat set boje u procesu sušenja otisaka emitiraju organske spojeve štetne za zdravlje i okoliš uopće. To je razlogom da se u posljednje vrijeme istražuju mogućnosti zamjene otapala u takvim bojama. Sadržaj naših opširnih istraživanja obuhvaćaju studiranje utjecaja zamjenske sirovine obnovljivog porijekla na tehnološke parametre u proizvodnji, kolorimetrijske karakteristike i kvalitetu otisaka te zbrinjavanje iskorištenih otisaka. U ovom radu prikazat će se jedan segment istraživanja vezan uz otpornost otisaka prema otiranju. U istraživanjima je korišten tribometar Pira Wallace kod kojeg se koristi sustav rotacije disk na disk. Rezultati analize ukazuju da se povećanjem udjela biljnog ulja u ofsetnoj boji ne utječe bitnije na otpornost prema otiranju. Zapažen je veći utjecaj tiskovne podloge. U radu se diskutira pojedinačno utjecaj svake boje CMY. Rezultati su interesantni u primjeni, posebno u tisku ambalaže.