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Diplomsko delo je rezultat preučevanja adsorpcije težkih ionov Pb2+, Cu2+ in Fe2+ na zeolit. Ker so ti ioni zelo močni onesnaževalci okolja, se pojavlja vprašanje kako zaščititi naravo pred njihovimi škodljivimi vplivi. Ena iz med možnosti je adsorpcija ionov na močen adsorbent, kar je v našem primeru zeolit. Tako je bistveno, da dobro spoznamo zeolit, preučimo njegovo strukturo in lastnosti, ter nato z različnimi kemijskimi analizami določimo, kakšne zmožnosti adsorpcije ima zeolit. Namen diplomske naloge je bil določiti adsorpcijske lastnosti zeolita v raztopini za adsorpcijo ionov težkih kovin ( Cu2+, Fe2+, Pb2+ ), določiti masne koncentracije kovinskih ionov z optično emisijsko spektroskopijo (ICP OES), ter preučiti specifiko samega zeolita (zeta potencial, specifična površina, velikost delcev). Za ugotavljanje adsopcijskih lastnosti zeolita smo spreminjali dva ključna parametra, koncentracijo raztopine težkih ionov, ter pH raztopine. S spreminjanjem teh parametrov smo prišli do ugotovitve, da so najbolj optimalni pogoji za adsorpcijo pri koncentraciji 13 mM in pri pH vrednosti 7. S preiskovanjem vpliva koncentracije težkih ionov na adsorbent smo ugotovili, da uspešnost adsorpcije pri višji koncentraciji upada, izjema je le baker. Pri spreminjanju pH vrednosti, pa se je izkazalo, da pH nima takšen velik vpliv na adsorpcijo kot jo ima koncentracija, saj smo ugotovili, da se adsorpcijska sposobnost malo zmanjša le pri zelo nizki pH vrednosti ( pH = 2,5 ). Ugotavljali smo tudi medsebojni vpliv ionov na učinkovitost adsorpcije ionov na zeolit, pri čemer se je izkazalo, da mešanica ionov v raztopini dobro vpliva na adsorpcijo, saj je bila v našem primeru učinkovitost adsorpcije za vse tri ione nad 99%. The diploma thesis is the result of studying the adsorption of heavy metal ions of Pb2+, Cu2+ and Fe2+ on zeolite. Since this ions are very powerful pollutants of the environment, the question arises as how to protect nature from their harmful effects. One of the possibilities is the adsorption of ions on a strong adsorbent, which in our case is zeolite. It is essential to get to know the zeolite well, to study its structure and properties, and then to determine, through various chemical analyzes, what is the zeolite's adsorption capacity. The purpose of this thesis was to determine the adsorption properties of zeolit for adsorption of heavy metal ions (Cu2+, Fe2+, Pb2+) in solution, to determine the mass concentrations of metal ions by optical emission spectroscopy (ICP OES), and to study the specificity of the zeolite itself (zeta potential, specific surface area, particle size). In order to determine the adsorption properties of zeolite, two key parameters, the concentration of the heavy metal ions in solution and the pH of the solution, have been studied. By changing these parameters, the most optimal conditions for adsorption were determined at a concentration of 13 mM and at a pH value of 7. By examining the influence of the concentration of heavy metal ions on the adsorbent, we found that the adsorption efficiency at a higher concentration decreases, with the exception of copper. When changing the pH value, it turned out that pH did not have as much effect on adsorption as the concentration, since we found that the adsorption efficiency decreased only at very low pH (pH = 2.5). We also investigated the interaction of ions on the adsorption efficiency of the zeolite, which showed that the mixture of ions in solution had a good effect on adsorption, since in our case the adsorption efficiency for all three ions was above 99%.

Vse ostrejši zakonodajni predpisi zahtevajo primerno in učinkovito predobdelavo in čiščenje industrijske odpadne vode. V ta namen je bila izvedena optimizacija čiščenja realne industrijske odpadne vode iz kovinsko predelovalne industrije tako, da je voda po postopku čiščenja primerna za ponovno uporabo v industrijskem procesu in ali vsaj za izpust v javno kanalizacijo. Cilj raziskave je bil iz industrijske odpadne vode odstraniti ione težkih kovin (aluminijeve-Al3+, bakrove-Cu2+ in železove Fe3+ ione). V raziskavi smo vzorcem industrijske odpadne vode analizirali fizikalno-kemijske parametre (temperaturo, pH vrednost, električno prevodnost, neraztopljene snovi, usedljive snovi, motnost, kemijsko potrebo po kisiku-KPK, biokemijsko potrebo po kisiku-BPK5 in koncentracijo Al3+, Cu2+ in Fe3+ ionov). Na vzorcih odpadne vode smo najprej preverili vpliv variiranja pH vrednosti, učinkovitost postopka nanofiltracije in flokulacije, ter na podlagi primerjave rezultatov pred in po čiščenju definirali optimalni postopek čiščenja. Eksperimenti so pokazali, da s postopkom nanofiltracije pri delovnem tlaku 10 bar, tangencialnem pretoku 1,6 L/min in izbrano NF2 membrano ter s predčiščenjem (7-12 µm filter) in variiranjem pH vrednosti s 5M HCl učinkovito odstranimo do 97% ionov Al3+, Cu2+ in Fe3+. Kot učinkovita metoda za čiščenje industrijske odpadne vode se je izkazala tudi flokulacija s flokulacijskim sredstvom CWL40 pri 160 obr/min in s 5 min končnim usedanjem. S postopkom flokulacije smo ione Al3+, Cu2+ in Fe3+ odstranil med 90-98%. Na podlagi rezultatov znižanja vrednosti fizikalno-kemijskih parametrov pod MDK za izpust v kanalizacijo, se je kot bolj zanesljiv proces čiščenja realne industrijske odpadne vode izkazal postopek nanofiltracije, s predčiščenjem in variiranjem pH vrednosti. Stricter legislative demands require proper and efficient pre-treatment and cleaning of industrial wastewater. In this work the optimization of real industrial wastewater treatment from a metal processing industry has been carried out in order to reuse the cleaned water in an industrial process or at least to be suitable for discharge directly into the sewage. The aim of this study was to remove heavy metal ions (Al3+, Cu2+, Fe3+) from real industrial wastewater. The physico-chemical parameters (temperature, pH value, electrical conductivity, undissolved substances, sedentary substances, opacity, chemical oxygen demand-COD, biochemical oxygen demand-BOD and concentration of Al3+, Cu2+ in Fe3+ ions) of industrial wastewater were analyzed. Firstly efficiency pH variation was tested, followed by nanofiltration and flocculation process. Based on a comparison of the results before and after the wastewater treatment an optimal cleaning procedure was established. Results have shown that nanofiltration process (with selected NF2 membrane) at a working pressure 10 bar, crossflow 1,6 L/min, applying pre-filtering (7-12 µm) and initial variation of the pH value with 5M HCl, effectively removes aluminium, copper and iron ions up to 97%. Flocculation process using the flocculant agent CWL40 at 160 rpm and after 5 min of settling proved to be an effective method for cleaning the industrial wastewater. Al3+, Cu2+ and Fe3+ ions were removed between 90-98%. Nanofiltration process with initial pH variation and pre-cleaning was defined as the optimal process for purification of real industrial wastewater, because of physico-chmemical parameters which values were suitable for discharge directly into the sewage.

Površinsko funkcionalizirani nanodelci silicijevega dioksida (SiO2) so v zadnjem času predmet številnih raziskav, ki obravnavajo odstranjevanje ionov težkih kovin iz različnih vodnih medijev. Nanodelci SiO2 se izkazujejo kot primerni zaradi svoje inertnosti, biokompatibilnosti, specifične površine in poroznosti, možnosti obdelave (funkcionaliziranja) površine ter enostavne in cenovno ugodne priprave. V diplomskem delu smo za pripravo amino-funkcionaliziranih SiO2 nanodelcev (SiO2@NH2) uporabili Stöber-jevo metodo, ki vključuje reakciji hidrolize in kondenzacije alkoksidnih prekurzorjev, kot sta tetraetoksisilan (TEOS) in 3-(trimetoksisililpropil) dietilentriamin (DETA), v alkoholnem mediju ob prisotnosti amoniaka kot katalizatorja. Na funkcionalnost pripravljenih SiO2 nanodelcev so vplivali sintezni pogoji (temperatura, čas, molsko razmerje voda:prekurzor, molsko razmerje med prekurzorji) in izbor prekurzorja, ki s svojimi amino (-NH2) funkcionalnimi skupinami omogoča vezavo in odstranjevanje ionov težkih kovin. Pripravljeni SiO2 in amino-funkcionalizirani SiO2 nanodelci (SiO2@NH2) so bili karakterizirani z uporabo različnih tehnik, kot so FT-IR spektroskopija, specifična površina (BET), presevna elektronska mikroskopija (TEM) in meritve zeta potenciala. S sintetiziranimi nanodelci smo proučevali učinkovitost vezave in odstranjevanja (adsorpcija) ionov težkih kovin, svinca (Pb2+) in kroma (Cr3+), iz modelnih raztopin soli. Učinkovitost odstranjevanja ionov težkih kovin je temeljila na osnovi meritev atomske absorpcijske spektroskopije (AAS). Rezultati so pokazali višjo tendenco vezave sintetiziranih SiO2 nanodelcev do Cr3+ ionov (~60%), v primerjavi z vezavo Pb2+ ionov (~33%), medtem ko je bila tendenca funkcionaliziranih SiO2 nanodelcev do obeh kovin približno enaka (~50%). Recently, surface-functionalized silicon dioxide (SiO2) nanoparticles are the subject of numerous research studies, which discuss the removal of heavy metal ions from different aquatic solutions. SiO2 nanoparticles are proven to be suitable because of their inertness, biocompatibility, specific surface area and porosity, surface treatment options (functionalization), are also simple and affordable. The research work on the preparation of amino-functionalized SiO2 nanoparticles (SiO2@NH2) was based on the Stöber method, which involves the reaction of hydrolysis and condensation of alkoxide precursors, such as tetraethoxysilane (TEOS) and 3- (trimethoxysilylpropyl) diethylenetriamine (DETA) in alcoholic media in the presence of ammonia as a catalyst. The functionality of SiO2 nanoparticles is influenced by synthesis conditions (temperature, time, molecular ratio of water:precursor, molar ration between the precursors) and selection of precursor, which with its amino (-NH2) functional groups allows to bond and remove the heavy metal ions. SiO2 and amino-functionalized SiO2 nanoparticles (SiO2@NH2) were characterized using a variety of techniques, such as FT-IR spectroscopy, specific surface area (BET), transmission electron microscopy (TEM) and zeta potential measurements. We have studied the binding efficiency (adsorption) of heavy metals ions, lead (Pb2 +) and chromium (Cr3+), by nanoparticles, from model salt solutions. Removal efficiency of heavy metal ions was calculated based on the measurements of atomic adsorption spectroscopy (AAS). The results showed a higher tendency towards synthesized SiO2 nanoparticles to Cr3 + ions (~ 60%), compared to the Pb2 + ions (~ 33%), while the tendency of functionalized SiO2 nanoparticles towards both metals was approximately similar (~ 50%).

We collected experimental kinetic rate constants for chemical processes responsible for the development and progress of neurodegeneration, focused on the enzymatic and non-enzymatic degradation of amine neurotransmitters and their reactive and neurotoxic metabolites. A gross scheme of neurodegeneration on the molecular level is based on two pathways. Firstly, reactive species oxidise heavy atom ions, which enhances the interaction with alpha-synuclein, thus promoting its folding to the beta form and giving rise to insoluble amyloid plaques. The latter prevents the function of vesicular transport leading to gradual neuronal death. In the second pathway, radical species, OH center dot in particular, react with the methylene groups of the apolar part of the lipid bilayer of either the cell or mitochondrial wall, resulting in membrane leakage followed by dyshomeostasis, loss of resting potential and neuron death. Unlike all other central neural system (CNS)-relevant biogenic amines, dopamine and noradrenaline are capable of a non-enzymatic auto-oxidative reaction, which produces hydrogen peroxide. This reaction is not limited to the mitochondrial membrane where scavenging enzymes, such as catalase, are located. On the other hand, dopamine and its metabolites, such as dopamine-o-quinone, dopaminechrome, 5,6-dihydroxyindole and indo-5,6-quinone, also interact directly with alpha-synuclein and reversibly inhibit plaque formation. We consider the role of the heavy metal ions, selected scavengers and scavenging enzymes, and discuss the relevance of certain foods and food supplements, including curcumin, garlic, N-acetyl cysteine, caffeine and red wine, as well as the long-term administration of non-steroid anti-inflammatory drugs and occasional tobacco smoking, that could all act toward preventing neurodegeneration. The current analysis can be employed in developing strategies for the prevention and treatment of neurodegeneration, and, hopefully, aid in the building of an overall kinetic molecular model of neurodegeneration itself.

Polimerne membrane se pogosto pojavljajo v različnih separacijskih procesih, kot npr. pri nanofiltraciji. Tankoplastne nanofiltracijske membrane (TFC NF) imajo sposobnost zadrževanja večvalentnih kationov, med njimi tudi ionov težkih kovin, vendar je njihova slabost ta, da se zaradi pojava koncentracijske polarizacije in mašenja (fouling) občutno zmanjša pretok skozi membrano. Namen modifikacije površine membrane je izboljšati njihovo selektivnost, ohraniti in povečati pretok skozi membrano (fluks), ohraniti stabilno strukturo, minimizirati nagnjenost k mašenju in s tem ugodno vplivati na separacijske lastnosti membran. V okviru raziskav za diplomsko delo je bila izvedena modifikacija komercialno dostopne tankoslojne kompozitne NF membrane (NF2, Sepro Inc.) ter njena karakterizacija pred in po modifikaciji. Modifikacijo smo izvedli v kislem in bazičnem mediju (s pomočjo citronske kisline in natrijevega hidroksida). Namen raziskav je bil primerjati učinek zadrževanja ionov težkih kovin (cink, kadmij, svinec) v kombinaciji z različnima anionoma (- NO3- oz. Cl-) pri filtraciji skozi modificirano in nemodificirano NF2 membrano. Filtracija je bil izvedena pri različnih delovnih pogojih (pH 4 in tlaku 5 20 in 44 bar). Na osnovi rezultatov filtracije, kot tudi iz analiz lastnosti (selektivnost, hidrofilnost, navidezna velikost por-NMWCO) osnovne in modificirane TFC NF2 membrane je razvidno, da lahko s preprosto kemijsko modifikacijo vplivamo na lastnosti membran v smislu površinskih karakteristik in morfološke strukture samega kompozita ter izboljšamo zadrževanje ionov težkih kovin, npr. pri delovnem tlaku 20 bar Pb2+ za 19% oz. 9% (iz raztopine PbNO3- oz. PbCl2), Cd2+ za 17% oz. 8% (iz raztopine CdNO3- oz. CdCl2) ter za Zn2+ za 4% oz. 8% (iz raztopine ZnNO3- oz. ZnCl2) glede na enako NF2 nemodificirano membrano. Polymeric membranes often appear in different separation processes, for instance in nanofiltration. Thin film composite membranes (TFC NF) have the ability to reject multivalent cations, including heavy metal ions. However its weakness is that because of concentration polarization the flux through the membrane considerably decreases. The purpose of membrane surface modification is to improve their selectivity, preserve and increase the flux, preserve the stable structure, minimize the fouling phenomena and in that way have a positive influence on separation characteristics of membranes. Within the research of my diploma thesis a modification of a basic commercially accessible thin composite NF membrane (NF2, Sepro Inc.) was carried out and its characterization before and after the modification. The modification was carried out in an acid and basic medium (using citric acid and sodium hydroxide). The purpose of the research was to compare effectiveness of heavy metal ions rejection (zinc, cadmium, lead) in the combination with different anions (- NO3- or Cl-) during the filtration process using the modified (6h KM NF2) and non-modified NF2 membrane. The model filtration solutions were prepared as clear solutions of metal salts. The filtration was carried out under different operating conditions (pH 4 pressure 5 20 and 44 bar). Based on the filtration efficiency results as well as from the characteristics (selectivity, hydrophilicity, molecular weight cut off-NMWCO) of basic and modified TFC NF2 membranes it can be stated that the membrane quality in the sense of surface characteristics and morphological structure of a composite can be influenced by a simple chemical modification. The filtration show that the surface modification of NF membranes can be effective in terms of heavy metal ions retention, e.g. at 20 bar Pb2+ retention from Pb(NO3)2 and PbCl2 solution is improved for 19% and 9%, respectively in comparison to non-modified membrane. Similarly the retention of Cd2+ from Cd(NO3)2 and CdCl2 solution is improved for 17% and 8% respectively and the retention of Zn2+ from Zn(NO3)2 and ZnCl2 for 4% and 9% respectively in comparison to the some NF2 non-modified membrane.