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Addressing contemporary environmental and health concerns requires reducing pollutant emissions and converting them into less harmful or valuable compounds within the framework of the circular economy. Guefoam materials offer a promising solution by enabling the capture and pre-concentration of volatile organic compounds (VOCs), while facilitating the structuring of active phases for heterogeneous catalytic conversions. This study demonstrates the benefits of merging two newly designed electromagnetic induction-assisted ceramic matrix Guefoams into a portable integrated unit, synergizing the pre-concentration and chemical transformation of n-hexane, a VOC with special challenges. One Guefoam serves as an adsorbent, whereas the other plays a catalytic role. These Guefoams host guest phases, which consist of composite materials combining a steel core with magneto-inductive properties encased in a highly porous carbonaceous layer. This carbonaceous material undertakes a dual mission: adsorbing n-hexane from a nitrogen stream within the adsorptive Guefoam and, upon phosphorus doping in the catalytic Guefoam, orchestrating the metal-free selective dehydroaromatization of n-hexane into benzene. The design and integration of these novel Guefoam materials into a unified functional entity prove highly effective in pre-concentrating (enrichment factors up to 275) and catalyzing n-hexane with up to 84 % conversion and 94 % benzene selectivity while remaining energy-efficient and environmentally sustainable.

Kaempferia galanga L. rhizomes contain ethyl trans-p-methoxycinnamate as a major secondary metabolite compound and biomarker. Various extraction methods with different solvents can isolate ethyl trans-p-methoxycinnamate with potential bioactivities. This paper reported the isolation of ethyl trans-p-methoxycinnamate from two varieties of K. galanga L. rhizomes by maceration in n-hexane. The small and large varieties of K. galanga samples produced ethyl trans-p-methoxycinnamate in 1.43% and 1.84% yields, higher than other methods and polar solvents of previous research. Structural elucidation of the obtained ethyl trans-p-methoxycinnamate was performed by FTIR, MS, and 1H NMR spectroscopies.

Kaempferia galanga L. rhizomes contain ethyl trans-p-methoxycinnamate as a major secondary metabolite compound and biomarker. Various extraction methods with different solvents can isolate ethyl trans-p-methoxycinnamate with potential bioactivities. This paper reported the isolation of ethyl trans-p-methoxycinnamate from two varieties of K. galanga L. rhizomes by maceration in n-hexane. The small and large varieties of K. galanga samples produced ethyl trans-p-methoxycinnamate in 1.43% and 1.84% yields, higher than other methods and polar solvents of previous research. Structural elucidation of the obtained ethyl trans-p-methoxycinnamate was performed by FTIR, MS, and 1H NMR spectroscopies.

The purpose of this bachelor thesis is to optimize pretreatment of a wastewater from cosmetic industry. The current cleaning process in industry consists of two steps, namely i) AOP (Advanced Oxidation Process), and ii) flocculation/flotation (FF). However, as the HEM (n-Hexane Extractable Materials) decreases the efficiency of the AOP process by heavily blocking the light to penetrate in the wastewater to be cleaned, a first FF in acid environment is introduced in the process as pretreatment. The parameters that were varied to carry out the optimization were i) Fe2(SO4)3 content added in first FF and, ii) H2O2 content. To precise, JAR tests were carried out to make the FF and the sample was put in a 1.8 L reactor and subjected to UV light in the AOP treatment. For the better distribution of the H2O2 and Fe2(SO4)3 addition to the cleaning process the design of experiment was used. The HEM measured was carried out according to standard method “United States Environmental Protection Agency (EPA), Method 1664, Revision B: n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry”. We found that the percentage of removal is very high, it goes from 96.3% till more that 99.9%. In average, with this new first FF, the percentage of removal is 98.61% which represents a very high enough removal rate of HEM to achieve the WW disposal limits in most cases. Only 3 out of 9 experiments exceeded the emission limit of 100 mg/L of HEM due to the type of surfactant, which we can conclude it has a strong influence in the removal of HEM., Namen tega diplomskega dela je optimizacija predobdelave odpadne vode iz kozmetične industrije. Sedanji process čiščenja v industriji je sestavljen in dveh korakov: 1) napredni oksidacijski procesi (ang. Advanced Oxidation Process-AOP) in 2) flokulacije/flotacije (FF). Prisotnost težkohlapnih lipofilnih snovi (TLS) znižuje učinkovitost AOP z preprečevanjem penetracije svetlobe v odpadno vodo, ki jo čistimo, zato smo uvedli predobdelavo FF v proces v kislem okolju. Parametri, ki smo jih spreminjali tekom optimizacije so bile: 1) dodatek Fe2(SO4)3 v prvi FF in 2) dodatek H2O2. FF process smo izvedli v t.i. Jar testu in potem smo 1.8 L vzorca smo dali v reaktor, ki smo ga izpostavili UV svetlobi v AOP obdelave. Za boljo razporeditev dodatka H2O2 in Fe2(SO4)3 v process čiščenja smo uporabili načrtovanje eksperimentov. Meritev LS smo izvedli glede na standard United States Environmental Protection Agency (EPA), Method 1664, Revision B: n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry”. Ugotovili smo, da je bila uspešno odstranjevanja zelo visok, od 96,3% pa vse do 99,9%. V povprečju z novo začetno FF kar predstavlja dovolj visoko odstranjevanja TLS za doseganje mejne vrednosti za izpust odpadne vode v večini primerov. Samo 3 od 9-ih poskusov presegajo mejno vrednost TLS 100 mg/L, zaradi tipa površinsko aktivnih snovi, za katere lahko zaključimo, da ima velik vpliv na odstranjevanj TLSa., Departamento de Ingeniería Química y Tecnología del Medio Ambiente, Grado en Ingeniería Química

This dissertation addresses the structure and properties of a number of polymer-based materials when they come into contact with specific environments. The first part describes the migration and depletion of active substances from insecticide-impregnated polyethylene sheets in water and air at different humidity levels and higher temperatures. In the second part, the structure, crystallization kinetics, and mechanical and transport properties of multilayer polymer films, consisting of metallocene (mPE) and low-density (LDPE) polyethylene layers, and in some cases also with layers of poly(ethylene-co-vinyl alcohol) and a polyethylene compatibilizer were investigated. Furthermore, inhomogeneous swelling was observed in the 2-layer films containing mPE and LDPE due to differences in the uptake of n-hexane (and limonene) in the respective film layers. These differences caused a bending/curvature of the film upon exposure to the vapour. This effect was further evaluated to determine whether solvent-induced bending could be used as a passive sensor to detect the presence and content of volatile organic compounds in air (VOC). The third part of this thesis describes the possibility of producing biopolymer materials based on larvae from the black soldier fly. After adding a plasticizer to the degreased larval material, protein-based biopolymer films were prepared via compression-moulding. The lipid extracted from the degreasing operation could potentially be used in various applications, such as those involving lubricants. In the last part of this work the release of micro- and nano-particles were determined from a polypropylene nanoclay-composite in a commonly occurring environment for plastics (air at elevated temperature). A prototype exposure chamber was built, and a method was developed to allow aging (degradation) of the sample in this chamber and analyze the effects of aging on the sample., Denna avhandling behandlar struktur och egenskaper hos ett antal polymerbaserade material i kontakt med vissa specifika miljöer. Den första delen behandlar migration och utarmning av aktiva substanser från insekticid-impregnerade polyetenplattor i vatten och luft vid olika luftfuktigheter och högre temperatur. I den andra delen studerades strukturen, kristallisationskinetiken samt mekaniska och transportegenskaper hos flerskiktade polymerfilmer uppbyggda av metallocen-polyeten (mPE) och lågdensitetspolyeten (LDPE), och i vissa fall också med skikt av poly(etylen-co-vinylalkohol) och en polyetenkompatibilisator. Vidare observerades en inhomogen svällning i 2-skiktsfilmen med mPE och LDPE, på grund av skillnader i upptag av n-hexan (och limonen) i respektive filmskikt, vilket orsakade en böjning/krökning av filmen vid exponering för ångan. Denna effekt utvärderades ytterligare för att se om den lösningsmedelsinducerade böjningen kunde användas som en passiv sensor för att detektera närvaron och halten av flyktiga organiska föreningar i luft (VOC). I den tredje delen av detta arbete visades möjligheten att producera biopolymer-material baserat på larver (Svart soldatfluga). Efter tillsats av en mjukgörare till det avfettade larvmaterialet framställdes protein-baserade biopolymerfilmer genom kompressionsgjutning. Den extraherade lipiden från avfettningen kan potentiallt också användas i olika applikationer, såsom i smörjmedel. I den sista delen av detta arbete undersöktes frisättningen av mikro- och nanopartiklar från en nanokomposit av polypropen och nanolera i en vanlig miljö för plast (luft vid förhöjd temperatur). En prototyp-exponeringskammare konstruerades och en metodik utvecklades för att kunna åldra (bryta ned) provet i denna kammare och analysera effekten av åldrandet., QC 2021-09-07

The purpose of this bachelor thesis is to optimize pretreatment of a wastewater from cosmetic industry. The current cleaning process in industry consists of two steps, namely i) AOP (Advanced Oxidation Process), and ii) flocculation/flotation (FF). However, as the HEM (n-Hexane Extractable Materials) decreases the efficiency of the AOP process by heavily blocking the light to penetrate in the wastewater to be cleaned, a first FF in acid environment is introduced in the process as pretreatment. The parameters that were varied to carry out the optimization were i) Fe2(SO4)3 content added in first FF and, ii) H2O2 content. To precise, JAR tests were carried out to make the FF and the sample was put in a 1.8 L reactor and subjected to UV light in the AOP treatment. For the better distribution of the H2O2 and Fe2(SO4)3 addition to the cleaning process the design of experiment was used. The HEM measured was carried out according to standard method “United States Environmental Protection Agency (EPA), Method 1664, Revision B: n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry”. We found that the percentage of removal is very high, it goes from 96.3% till more that 99.9%. In average, with this new first FF, the percentage of removal is 98.61% which represents a very high enough removal rate of HEM to achieve the WW disposal limits in most cases. Only 3 out of 9 experiments exceeded the emission limit of 100 mg/L of HEM due to the type of surfactant, which we can conclude it has a strong influence in the removal of HEM., Namen tega diplomskega dela je optimizacija predobdelave odpadne vode iz kozmetične industrije. Sedanji process čiščenja v industriji je sestavljen in dveh korakov: 1) napredni oksidacijski procesi (ang. Advanced Oxidation Process-AOP) in 2) flokulacije/flotacije (FF). Prisotnost težkohlapnih lipofilnih snovi (TLS) znižuje učinkovitost AOP z preprečevanjem penetracije svetlobe v odpadno vodo, ki jo čistimo, zato smo uvedli predobdelavo FF v proces v kislem okolju. Parametri, ki smo jih spreminjali tekom optimizacije so bile: 1) dodatek Fe2(SO4)3 v prvi FF in 2) dodatek H2O2. FF process smo izvedli v t.i. Jar testu in potem smo 1.8 L vzorca smo dali v reaktor, ki smo ga izpostavili UV svetlobi v AOP obdelave. Za boljo razporeditev dodatka H2O2 in Fe2(SO4)3 v process čiščenja smo uporabili načrtovanje eksperimentov. Meritev LS smo izvedli glede na standard United States Environmental Protection Agency (EPA), Method 1664, Revision B: n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry”. Ugotovili smo, da je bila uspešno odstranjevanja zelo visok, od 96,3% pa vse do 99,9%. V povprečju z novo začetno FF kar predstavlja dovolj visoko odstranjevanja TLS za doseganje mejne vrednosti za izpust odpadne vode v večini primerov. Samo 3 od 9-ih poskusov presegajo mejno vrednost TLS 100 mg/L, zaradi tipa površinsko aktivnih snovi, za katere lahko zaključimo, da ima velik vpliv na odstranjevanj TLSa., Departamento de Ingeniería Química y Tecnología del Medio Ambiente, Grado en Ingeniería Química

This dissertation addresses the structure and properties of a number of polymer-based materials when they come into contact with specific environments. The first part describes the migration and depletion of active substances from insecticide-impregnated polyethylene sheets in water and air at different humidity levels and higher temperatures. In the second part, the structure, crystallization kinetics, and mechanical and transport properties of multilayer polymer films, consisting of metallocene (mPE) and low-density (LDPE) polyethylene layers, and in some cases also with layers of poly(ethylene-co-vinyl alcohol) and a polyethylene compatibilizer were investigated. Furthermore, inhomogeneous swelling was observed in the 2-layer films containing mPE and LDPE due to differences in the uptake of n-hexane (and limonene) in the respective film layers. These differences caused a bending/curvature of the film upon exposure to the vapour. This effect was further evaluated to determine whether solvent-induced bending could be used as a passive sensor to detect the presence and content of volatile organic compounds in air (VOC). The third part of this thesis describes the possibility of producing biopolymer materials based on larvae from the black soldier fly. After adding a plasticizer to the degreased larval material, protein-based biopolymer films were prepared via compression-moulding. The lipid extracted from the degreasing operation could potentially be used in various applications, such as those involving lubricants. In the last part of this work the release of micro- and nano-particles were determined from a polypropylene nanoclay-composite in a commonly occurring environment for plastics (air at elevated temperature). A prototype exposure chamber was built, and a method was developed to allow aging (degradation) of the sample in this chamber and analyze the effects of aging on the sample., Denna avhandling behandlar struktur och egenskaper hos ett antal polymerbaserade material i kontakt med vissa specifika miljöer. Den första delen behandlar migration och utarmning av aktiva substanser från insekticid-impregnerade polyetenplattor i vatten och luft vid olika luftfuktigheter och högre temperatur. I den andra delen studerades strukturen, kristallisationskinetiken samt mekaniska och transportegenskaper hos flerskiktade polymerfilmer uppbyggda av metallocen-polyeten (mPE) och lågdensitetspolyeten (LDPE), och i vissa fall också med skikt av poly(etylen-co-vinylalkohol) och en polyetenkompatibilisator. Vidare observerades en inhomogen svällning i 2-skiktsfilmen med mPE och LDPE, på grund av skillnader i upptag av n-hexan (och limonen) i respektive filmskikt, vilket orsakade en böjning/krökning av filmen vid exponering för ångan. Denna effekt utvärderades ytterligare för att se om den lösningsmedelsinducerade böjningen kunde användas som en passiv sensor för att detektera närvaron och halten av flyktiga organiska föreningar i luft (VOC). I den tredje delen av detta arbete visades möjligheten att producera biopolymer-material baserat på larver (Svart soldatfluga). Efter tillsats av en mjukgörare till det avfettade larvmaterialet framställdes protein-baserade biopolymerfilmer genom kompressionsgjutning. Den extraherade lipiden från avfettningen kan potentiallt också användas i olika applikationer, såsom i smörjmedel. I den sista delen av detta arbete undersöktes frisättningen av mikro- och nanopartiklar från en nanokomposit av polypropen och nanolera i en vanlig miljö för plast (luft vid förhöjd temperatur). En prototyp-exponeringskammare konstruerades och en metodik utvecklades för att kunna åldra (bryta ned) provet i denna kammare och analysera effekten av åldrandet., QC 2021-09-07

The purpose of this bachelor thesis is to optimize pretreatment of a wastewater from cosmetic industry. The current cleaning process in industry consists of two steps, namely i) AOP (Advanced Oxidation Process), and ii) flocculation/flotation (FF). However, as the HEM (n-Hexane Extractable Materials) decreases the efficiency of the AOP process by heavily blocking the light to penetrate in the wastewater to be cleaned, a first FF in acid environment is introduced in the process as pretreatment. The parameters that were varied to carry out the optimization were i) Fe2(SO4)3 content added in first FF and, ii) H2O2 content. To precise, JAR tests were carried out to make the FF and the sample was put in a 1.8 L reactor and subjected to UV light in the AOP treatment. For the better distribution of the H2O2 and Fe2(SO4)3 addition to the cleaning process the design of experiment was used. The HEM measured was carried out according to standard method “United States Environmental Protection Agency (EPA), Method 1664, Revision B: n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry”. We found that the percentage of removal is very high, it goes from 96.3% till more that 99.9%. In average, with this new first FF, the percentage of removal is 98.61% which represents a very high enough removal rate of HEM to achieve the WW disposal limits in most cases. Only 3 out of 9 experiments exceeded the emission limit of 100 mg/L of HEM due to the type of surfactant, which we can conclude it has a strong influence in the removal of HEM., Namen tega diplomskega dela je optimizacija predobdelave odpadne vode iz kozmetične industrije. Sedanji process čiščenja v industriji je sestavljen in dveh korakov: 1) napredni oksidacijski procesi (ang. Advanced Oxidation Process-AOP) in 2) flokulacije/flotacije (FF). Prisotnost težkohlapnih lipofilnih snovi (TLS) znižuje učinkovitost AOP z preprečevanjem penetracije svetlobe v odpadno vodo, ki jo čistimo, zato smo uvedli predobdelavo FF v proces v kislem okolju. Parametri, ki smo jih spreminjali tekom optimizacije so bile: 1) dodatek Fe2(SO4)3 v prvi FF in 2) dodatek H2O2. FF process smo izvedli v t.i. Jar testu in potem smo 1.8 L vzorca smo dali v reaktor, ki smo ga izpostavili UV svetlobi v AOP obdelave. Za boljo razporeditev dodatka H2O2 in Fe2(SO4)3 v process čiščenja smo uporabili načrtovanje eksperimentov. Meritev LS smo izvedli glede na standard United States Environmental Protection Agency (EPA), Method 1664, Revision B: n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry”. Ugotovili smo, da je bila uspešno odstranjevanja zelo visok, od 96,3% pa vse do 99,9%. V povprečju z novo začetno FF kar predstavlja dovolj visoko odstranjevanja TLS za doseganje mejne vrednosti za izpust odpadne vode v večini primerov. Samo 3 od 9-ih poskusov presegajo mejno vrednost TLS 100 mg/L, zaradi tipa površinsko aktivnih snovi, za katere lahko zaključimo, da ima velik vpliv na odstranjevanj TLSa., Departamento de Ingeniería Química y Tecnología del Medio Ambiente, Grado en Ingeniería Química

Currently, the population spends most of the time in indoor environments, which makes Indoor Air Quality (IAQ) very important for health and comfort. As vegetation can act as a biofilter capturing air pollutants, this study aims to assess the effectiveness of a living wall module in the removal of the Total Volatile Organic Compounds (TVOCs) for IAQ improvement. An airtight glass chamber was used to release contaminants, monitoring the TVOCs both with the chamber empty (control) and with a small Fytotextile® living wall module planted with Nephrolepis exaltata L. A substantial reduction of TVOCs was observed when the living wall was inside the chamber. In few hours, TVOCs levels were reduced below the recommended limit (following Spanish regulations). More tests are recommended considering different plant species and other variables related to the IAQ.

This dissertation addresses the structure and properties of a number of polymer-based materials when they come into contact with specific environments. The first part describes the migration and depletion of active substances from insecticide-impregnated polyethylene sheets in water and air at different humidity levels and higher temperatures. In the second part, the structure, crystallization kinetics, and mechanical and transport properties of multilayer polymer films, consisting of metallocene (mPE) and low-density (LDPE) polyethylene layers, and in some cases also with layers of poly(ethylene-co-vinyl alcohol) and a polyethylene compatibilizer were investigated. Furthermore, inhomogeneous swelling was observed in the 2-layer films containing mPE and LDPE due to differences in the uptake of n-hexane (and limonene) in the respective film layers. These differences caused a bending/curvature of the film upon exposure to the vapour. This effect was further evaluated to determine whether solvent-induced bending could be used as a passive sensor to detect the presence and content of volatile organic compounds in air (VOC). The third part of this thesis describes the possibility of producing biopolymer materials based on larvae from the black soldier fly. After adding a plasticizer to the degreased larval material, protein-based biopolymer films were prepared via compression-moulding. The lipid extracted from the degreasing operation could potentially be used in various applications, such as those involving lubricants. In the last part of this work the release of micro- and nano-particles were determined from a polypropylene nanoclay-composite in a commonly occurring environment for plastics (air at elevated temperature). A prototype exposure chamber was built, and a method was developed to allow aging (degradation) of the sample in this chamber and analyze the effects of aging on the sample., Denna avhandling behandlar struktur och egenskaper hos ett antal polymerbaserade material i kontakt med vissa specifika miljöer. Den första delen behandlar migration och utarmning av aktiva substanser från insekticid-impregnerade polyetenplattor i vatten och luft vid olika luftfuktigheter och högre temperatur. I den andra delen studerades strukturen, kristallisationskinetiken samt mekaniska och transportegenskaper hos flerskiktade polymerfilmer uppbyggda av metallocen-polyeten (mPE) och lågdensitetspolyeten (LDPE), och i vissa fall också med skikt av poly(etylen-co-vinylalkohol) och en polyetenkompatibilisator. Vidare observerades en inhomogen svällning i 2-skiktsfilmen med mPE och LDPE, på grund av skillnader i upptag av n-hexan (och limonen) i respektive filmskikt, vilket orsakade en böjning/krökning av filmen vid exponering för ångan. Denna effekt utvärderades ytterligare för att se om den lösningsmedelsinducerade böjningen kunde användas som en passiv sensor för att detektera närvaron och halten av flyktiga organiska föreningar i luft (VOC). I den tredje delen av detta arbete visades möjligheten att producera biopolymer-material baserat på larver (Svart soldatfluga). Efter tillsats av en mjukgörare till det avfettade larvmaterialet framställdes protein-baserade biopolymerfilmer genom kompressionsgjutning. Den extraherade lipiden från avfettningen kan potentiallt också användas i olika applikationer, såsom i smörjmedel. I den sista delen av detta arbete undersöktes frisättningen av mikro- och nanopartiklar från en nanokomposit av polypropen och nanolera i en vanlig miljö för plast (luft vid förhöjd temperatur). En prototyp-exponeringskammare konstruerades och en metodik utvecklades för att kunna åldra (bryta ned) provet i denna kammare och analysera effekten av åldrandet., QC 2021-09-07

This dissertation addresses the structure and properties of a number of polymer-based materials when they come into contact with specific environments. The first part describes the migration and depletion of active substances from insecticide-impregnated polyethylene sheets in water and air at different humidity levels and higher temperatures. In the second part, the structure, crystallization kinetics, and mechanical and transport properties of multilayer polymer films, consisting of metallocene (mPE) and low-density (LDPE) polyethylene layers, and in some cases also with layers of poly(ethylene-co-vinyl alcohol) and a polyethylene compatibilizer were investigated. Furthermore, inhomogeneous swelling was observed in the 2-layer films containing mPE and LDPE due to differences in the uptake of n-hexane (and limonene) in the respective film layers. These differences caused a bending/curvature of the film upon exposure to the vapour. This effect was further evaluated to determine whether solvent-induced bending could be used as a passive sensor to detect the presence and content of volatile organic compounds in air (VOC). The third part of this thesis describes the possibility of producing biopolymer materials based on larvae from the black soldier fly. After adding a plasticizer to the degreased larval material, protein-based biopolymer films were prepared via compression-moulding. The lipid extracted from the degreasing operation could potentially be used in various applications, such as those involving lubricants. In the last part of this work the release of micro- and nano-particles were determined from a polypropylene nanoclay-composite in a commonly occurring environment for plastics (air at elevated temperature). A prototype exposure chamber was built, and a method was developed to allow aging (degradation) of the sample in this chamber and analyze the effects of aging on the sample., Denna avhandling behandlar struktur och egenskaper hos ett antal polymerbaserade material i kontakt med vissa specifika miljöer. Den första delen behandlar migration och utarmning av aktiva substanser från insekticid-impregnerade polyetenplattor i vatten och luft vid olika luftfuktigheter och högre temperatur. I den andra delen studerades strukturen, kristallisationskinetiken samt mekaniska och transportegenskaper hos flerskiktade polymerfilmer uppbyggda av metallocen-polyeten (mPE) och lågdensitetspolyeten (LDPE), och i vissa fall också med skikt av poly(etylen-co-vinylalkohol) och en polyetenkompatibilisator. Vidare observerades en inhomogen svällning i 2-skiktsfilmen med mPE och LDPE, på grund av skillnader i upptag av n-hexan (och limonen) i respektive filmskikt, vilket orsakade en böjning/krökning av filmen vid exponering för ångan. Denna effekt utvärderades ytterligare för att se om den lösningsmedelsinducerade böjningen kunde användas som en passiv sensor för att detektera närvaron och halten av flyktiga organiska föreningar i luft (VOC). I den tredje delen av detta arbete visades möjligheten att producera biopolymer-material baserat på larver (Svart soldatfluga). Efter tillsats av en mjukgörare till det avfettade larvmaterialet framställdes protein-baserade biopolymerfilmer genom kompressionsgjutning. Den extraherade lipiden från avfettningen kan potentiallt också användas i olika applikationer, såsom i smörjmedel. I den sista delen av detta arbete undersöktes frisättningen av mikro- och nanopartiklar från en nanokomposit av polypropen och nanolera i en vanlig miljö för plast (luft vid förhöjd temperatur). En prototyp-exponeringskammare konstruerades och en metodik utvecklades för att kunna åldra (bryta ned) provet i denna kammare och analysera effekten av åldrandet., QC 2021-09-07

This dissertation addresses the structure and properties of a number of polymer-based materials when they come into contact with specific environments. The first part describes the migration and depletion of active substances from insecticide-impregnated polyethylene sheets in water and air at different humidity levels and higher temperatures. In the second part, the structure, crystallization kinetics, and mechanical and transport properties of multilayer polymer films, consisting of metallocene (mPE) and low-density (LDPE) polyethylene layers, and in some cases also with layers of poly(ethylene-co-vinyl alcohol) and a polyethylene compatibilizer were investigated. Furthermore, inhomogeneous swelling was observed in the 2-layer films containing mPE and LDPE due to differences in the uptake of n-hexane (and limonene) in the respective film layers. These differences caused a bending/curvature of the film upon exposure to the vapour. This effect was further evaluated to determine whether solvent-induced bending could be used as a passive sensor to detect the presence and content of volatile organic compounds in air (VOC). The third part of this thesis describes the possibility of producing biopolymer materials based on larvae from the black soldier fly. After adding a plasticizer to the degreased larval material, protein-based biopolymer films were prepared via compression-moulding. The lipid extracted from the degreasing operation could potentially be used in various applications, such as those involving lubricants. In the last part of this work the release of micro- and nano-particles were determined from a polypropylene nanoclay-composite in a commonly occurring environment for plastics (air at elevated temperature). A prototype exposure chamber was built, and a method was developed to allow aging (degradation) of the sample in this chamber and analyze the effects of aging on the sample., Denna avhandling behandlar struktur och egenskaper hos ett antal polymerbaserade material i kontakt med vissa specifika miljöer. Den första delen behandlar migration och utarmning av aktiva substanser från insekticid-impregnerade polyetenplattor i vatten och luft vid olika luftfuktigheter och högre temperatur. I den andra delen studerades strukturen, kristallisationskinetiken samt mekaniska och transportegenskaper hos flerskiktade polymerfilmer uppbyggda av metallocen-polyeten (mPE) och lågdensitetspolyeten (LDPE), och i vissa fall också med skikt av poly(etylen-co-vinylalkohol) och en polyetenkompatibilisator. Vidare observerades en inhomogen svällning i 2-skiktsfilmen med mPE och LDPE, på grund av skillnader i upptag av n-hexan (och limonen) i respektive filmskikt, vilket orsakade en böjning/krökning av filmen vid exponering för ångan. Denna effekt utvärderades ytterligare för att se om den lösningsmedelsinducerade böjningen kunde användas som en passiv sensor för att detektera närvaron och halten av flyktiga organiska föreningar i luft (VOC). I den tredje delen av detta arbete visades möjligheten att producera biopolymer-material baserat på larver (Svart soldatfluga). Efter tillsats av en mjukgörare till det avfettade larvmaterialet framställdes protein-baserade biopolymerfilmer genom kompressionsgjutning. Den extraherade lipiden från avfettningen kan potentiallt också användas i olika applikationer, såsom i smörjmedel. I den sista delen av detta arbete undersöktes frisättningen av mikro- och nanopartiklar från en nanokomposit av polypropen och nanolera i en vanlig miljö för plast (luft vid förhöjd temperatur). En prototyp-exponeringskammare konstruerades och en metodik utvecklades för att kunna åldra (bryta ned) provet i denna kammare och analysera effekten av åldrandet., QC 2021-09-07

Currently, the population spends most of the time in indoor environments, which makes Indoor Air Quality (IAQ) very important for health and comfort. As vegetation can act as a biofilter capturing air pollutants, this study aims to assess the effectiveness of a living wall module in the removal of the Total Volatile Organic Compounds (TVOCs) for IAQ improvement. An airtight glass chamber was used to release contaminants, monitoring the TVOCs both with the chamber empty (control) and with a small Fytotextile® living wall module planted with Nephrolepis exaltata L. A substantial reduction of TVOCs was observed when the living wall was inside the chamber. In few hours, TVOCs levels were reduced below the recommended limit (following Spanish regula tions). More tests are recommended considering different plant species and other variables related to the IAQ.

Automotive technicians are commonly exposed to organic and chlorinated solvents, particularly through use of cleaning products. Mainly during the period 1989-2002, n-hexane was a component of some of these products. In other occupational contexts, n-hexane has been shown to be a cause of peripheral neuropathy. The purpose of the present study was to investigate whether previous exposures to low concentrations of n-hexane were a cause of persistent peripheral neuropathy in automotive technicians. Enrolled in the study were 830 San Francisco Bay Area automotive technicians. Each participant underwent a battery of tests to investigate peripheral nervous system impairment. Test results regressed against estimated hexane and total solvent exposures showed only limited evidence of association with solvent exposures. Exposures to both hexane and general solvents were well below their occupational exposure limits. Generally, our results provide reassurance about persistent peripheral neuropathic effects in automotive technicians who previously used hexane-containing automotive cleaning products. This may reflect repair processes, since the exposures occurred some years previous to the study. However, we cannot exclude the possibility that the absence of observed effect in this study may be attributable to low exposures, exposure misclassification and/or the healthy worker survivor effect.

The hydroisomerization of linear or low branched alkanes through alkenes is a significant process for the refining of C5 to C6 hydrocarbon fractions to increase the octane number of automotive fuels. The hydroisomerization leads to the conversion of linear alkanes with a low octane number to branched isomers with a sufficiently high octane number. The bifunctional heterogeneous catalysts are a combination of an acid catalyst consisting of oxides containing acidic active centers and a metal cluster, where the hydrogenation and dehydrogenation of hydrocarbon reactants take place. The zeolite-based catalysts are significant in petroleum industry for the hydroisomerization of alkanes, especially the MOR zeolite type. However, availability of active sites for the n-hexane molecule in MOR zeolite is restricted by slow diffusion in narrow channels, and overall efficiency of the catalytic process is thus limited by transport of molecules. Branched alkanes diffuse even more slowly than linear n-alkanes due to of the higher kinetic diameter. The access of acidic active sites in current industrial catalysts is typically increased by partial dealumination of zeolites, where the aluminum atoms are extracted from the framework of zeolite resulting in positive textural changes in the channel structure of the zeolite but at the same time lowering the concentration of active acidic Br?nsted centers. For these reasons, various post-synthesis methods of zeolites such as desilication, dealumination and fluoridation have been used in this work. The texture parameters of zeolites are adjusted by combination of these methods and allow easier transport of the hydrocarbon molecules to the active sites, therefore achieving a substantial increase in the rate of hydroisomerization reaction and shifting the reaction conditions to lower temperatures where the thermodynamic equilibrium is inclined to forming of multi-branched alkanes. Another important parameter for the hydroisomerization of C6 i, Hydroizomerizace lineárních nebo málo větvených alkanů, prostřednictvím alkenů, je významným procesem pro rafinaci C5 až C6 uhlovodíkových frakcí s cílem zvýšit oktanové číslo automobilových paliv. Hydroizomerizace vede k transformaci lineárních alkanů s nízkým oktanovým číslem na větvené izomery s dostatečně vysokým oktanovým číslem. Pro hydroizomerizaci alkanů se osvědčilo použití bifunkčních heterogenních katalyzátorů, které jsou kombinací kyselého katalyzátoru složeného z oxidů obsahujících kyselá aktivní centra a klastrů kovu, kde probíhá hydrogenace a dehydrogenace uhlovodíkových reaktantů. V ropném průmyslu jsou pro hydroizomeraci alkanů významné katalyzátory na bázi zeolitu, zejména typu MOR. Nicméně, dostupnost aktivních center pro molekulu C6 v MOR zeolitu je omezena pomalou difuzí úzkým kanálem a celková účinnost katalytického procesu je tak limitována transportními jevy. Větvené alkany vzhledem k vyššímu kinetickému průměru difundují ještě pomaleji než lineární n-alkany. Dostupnost kyselých aktivních center v současných průmyslových katalyzátorech je typicky zvyšována částečnou dealuminací zeolitů, kdy dochází k extrakci části atomů hliníku ze strukturní mřížky, což vede k pozitivním texturním změnám v kanálové struktuře zeolitu, ale zároveň ke snížení koncentrace aktivních kyselých Br?nstedovských center, jejichž přítomnost v zeolitu je podmíněna přítomností hliníku ve strukturní mřížce zeolitu. Z těchto důvodů byly v této práci použity různé post-syntézní úpravy zeolitů jako je desilikace, dealuminace a fluoridace. Jejich kombinací se upraví texturní parametry zeolitů, což umožní snadnější transport molekul uhlovodíků k aktivním centrům, a tím se dosáhne podstatného zvýšení rychlosti hydroizomerizační reakce, a posunu reakčních podmínek k nižším teplotám, kde je termodynamická rovnováha nakloněna k tvorbě vícerozvětvených alkánů. Dalším důležitým parametrem pro hydroizomerizaci C6 je množství kyselých center obsažených v zeolitech. Analýza role zvýšené, Fakulta chemicko-technologická, Předseda komise pro obhajobu disertační práce Ing. Jany Pastvové, doc. Svoboda, nechal hlasovat o pokračování obhajoby za nepřítomnosti jednoho z oponentů (prof. Čapek). Komise vyslovila souhlas. Poté Ing. Petr Sazama, Ph.D. přednesl stanovisko školitele a následně prof. Šulcová seznámila přítomné se stanoviskem školícího pracoviště. Bylo konstatováno, že studentka splnila všechny studijní povinnosti. Poté Ing. Pastvová přednesla členům komise výsledky své disertační práce formou prezentace. Oponenti v pořadí doc. Sobalík a doc. Bernauer přednesli své posudky. Posudek prof. Čapka přednesl předseda komise. Oponenti obdrželi odpovědi na své připomínky v písemné formě před začátkem obhajoby. V další části obhajoby probíhala diskuze se členy komise a oponenty. Autorka práce reagovala na vznesené dotazy. Komise doporučila děkanovi fakulty udělit Ing. Pastvové titul Ph.D.

This paper describes a study of the nature and the accessibility of the acid sites in micromesoporous mordenite zeolites obtained by desilication and dealumination and analysis of their activity and selectivity in the hydroisomerization of n-hexane. Alkaline-acid, acid-alkaline-acid, and fluorination-alkaline-acid postsynthesis treatments were employed for the preparation of micromesoporous mordenites. The FTIR spectra of adsorbed d(3)-acetonitrille, Al-27 MAS NMR, HR-TEM, and N-2 adsorption were used for quantitative analysis of the Bronsted and Lewis sites, the coordination of Al atoms, and the textural properties. The alkaline treatment causes desilication, preferably occurring along the crystal defects and resulting in the formation of a secondary mesoporous structure characterized by 5-20 nm cavities and the formation of extraframework (Al-Ex) species and terminal Si-OH groups. The Al-Ex species formed by hydrolysis of perturbed or dislodged framework Al easily restrict part of the pseudomonodimensional channel structure of mordenite. The subsequent removal of Al-Ex by mild acid leaching or simultaneous removal of Si and Al atoms by desilication of fluorinated zeolite result in a micromesoporous structure with a large number of unrestricted channel openings and lead to a large increase in the accessibility of 01-1 groups for n-hexane. Thus, the sequential leaching treatments enable the formation of active acid sites in an environment of nonrestricted microporous channels with simultaneous enhancement of accessibility of the active sites and molecular transport. It is shown that the micromesoporous structure with high concentration of Bronsted sites of enhanced accessibility directs the hydroisomerization reaction toward high yields of branched isomers and shortening of the main 12-ring channels and that the larger numbers of channel openings result in an increase in selectivity, limiting nonselective subsequent cracking reactions., Tento článek popisuje studii o povaze a dostupnosti kyselých míst v mikromezoporózních mordenitových zeolitech získaných desilikací a dealuminací a analýzou jejich aktivity a selektivity při hydroizomeraci n-hexanu. Pro přípravu mikromezoporózních mordenitů byly použity kombinace alkalicko-kyselých, kyselých-alkalicko-kyselých a fluoridace-alkalicko-kyselých postsyntézních úprav. Spektra FTIR adsorbovaného d3-acetonitrilu, 27Al MAS NMR, HR-TEM a adsorpce N2 byla použita pro kvantitativní analýzu míst Brønsted a Lewis, koordinaci atomů Al a texturních vlastností. Alkalické zpracování způsobuje desilikaci, s výhodou se vyskytuje podél krystalových defektů a vede ke vzniku sekundární mezoporézní struktury charakterizované dutinami 5-20 nm a tvorba druhů mimoskeletálních Al (AlEx) a koncových Si-OH skupin. Typy AlEx tvořené hydrolýzou přerušeného nebo uvolněného Al snadno omezují část pseudomonimenzionální kanálové struktury mordenitu. Následné odstranění AlEx mírným kyselinovým loužením nebo současným odstraněním atomů Si a Al desilikací fluorovaného zeolitu vede k mikromezoporózní struktuře s velkým počtem neomezených kanálových otvorů a vede k velkému zvýšení dostupnosti OH skupin pro n-hexan. Sekvenční loužící postupy tedy umožňují tvorbu aktivních kyselých center v prostředí neomezených mikroporézních kanálů se současným zvýšením přístupnosti aktivních míst a molekulárního transportu. Ukazuje se, že mikromezoporézní struktura s vysokou koncentrací Brønstedových míst s vylepšenou dostupností vede v hydroizomerizační reakci k vysokému výtěžku rozvětvených izomerů a zkrácení hlavních 12-ti četných kanálků, a že větší počet kanálových otvorů vede ke zvýšení selektivity, omezením neselektivních následných krakovacích reakcí.

LEDs are made from semiconductor materials which combine Ga, Al and In with As, P and N, and other components contain metals such as Fe, Cu, Ni, Pb, Zn, Ag, Au and rare earth elements (REE). The recovery of critical and rare earth elements from spent LEDs is discussed in relation to future demand for these materials, in particular Ga, In, Ce, Eu, Gd and Y. There are three different approaches: direct re-use of lamp phosphors in new lamps, although this is only applicable to one type of fluorescent lamp; recycling of individual phosphor components, using physicochemical separation methods to pre-treat the phosphor mixture to separate the halophosphate phosphor fraction from the rare earth phosphors before recycling of its REE content; and chemical treatment of the phosphors with recovery of REE from solution by precipitation or solvent extraction. Separation of lamp phosphors by flotation is not easy because the components have similar hydrophobicity. The efficiency of the collectors dodecyl ammonium acetate, sodium dodecyl sulphate and sodium oleate has been tested at different pH values and the effect of sodium metasilicate as dispersant has also been investigated, with the results depending on the type of collector and pH. Two-liquid flotation using immiscible liquids consisting of water as a polar solvent and hexane, heptane or octane as non-polar solvent is more suitable for the separation of fine, less than 10 mm particles, and the wettability of the particles can be adjusted using a surfactant. Pneumatic separation in an air stream gave only moderate results. Separation of phosphor particles has been achieved using heavy medium separation, and the process was accelerated by centrifugation and particle pre-treatment with sodium oleate. Processes for the recovery of REEs from phosphors include leaching with HCl/H2O2, heating with sodium carbonate at 1000 degrees C, pressure leaching with H2SO4/HNO3, and extraction with supercritical CO2 containing tri-n-butyl ph, LEDs are made from semiconductor materials which combine Ga, Al and In with As, P and N, and other components contain metals such as Fe, Cu, Ni, Pb, Zn, Ag, Au and rare earth elements (REE). The recovery of critical and rare earth elements from spent LEDs is discussed in relation to future demand for these materials, in particular Ga, In, Ce, Eu, Gd and Y. There are three different approaches: direct re-use of lamp phosphors in new lamps, although this is only applicable to one type of fluorescent lamp; recycling of individual phosphor components, using physicochemical separation methods to pre-treat the phosphor mixture to separate the halophosphate phosphor fraction from the rare earth phosphors before recycling of its REE content; and chemical treatment of the phosphors with recovery of REE from solution by precipitation or solvent extraction. Separation of lamp phosphors by flotation is not easy because the components have similar hydrophobicity. The efficiency of the collectors dodecyl ammonium acetate, sodium dodecyl sulphate and sodium oleate has been tested at different pH values and the effect of sodium metasilicate as dispersant has also been investigated, with the results depending on the type of collector and pH. Two-liquid flotation using immiscible liquids consisting of water as a polar solvent and hexane, heptane or octane as non-polar solvent is more suitable for the separation of fine, less than 10 mm particles, and the wettability of the particles can be adjusted using a surfactant. Pneumatic separation in an air stream gave only moderate results. Separation of phosphor particles has been achieved using heavy medium separation, and the process was accelerated by centrifugation and particle pre-treatment with sodium oleate. Processes for the recovery of REEs from phosphors include leaching with HCl/H2O2, heating with sodium carbonate at 1000 degrees C, pressure leaching with H2SO4/HNO3, and extraction with supercritical CO2 containing tri-n-butyl ph

Occupational exposure to solvents, including n-hexane, has been associated with acquired color vision defects. Blue-yellow defects are most common and may be due to neurotoxicity or retinal damage. Acetone may potentiate the neurotoxicity of n-hexane. We present results on nonhexane solvent and hexane exposure and color vision from a cross-sectional study of 835 automotive repair workers in the San Francisco Bay Area, California (2007-2013). Cumulative exposure was estimated from self-reported work history, and color vision was assessed using the Lanthony desaturated D-15 panel test. Log-binomial regression was used to estimate prevalence ratios for color vision defects. Acquired color vision defects were present in 29% of participants, of which 70% were blue-yellow. Elevated prevalence ratios were found for nonhexane solvent exposure, with a maximum of 1.31 (95% confidence interval (CI): 0.86, 2.00) for blue-yellow. Among participants aged ≤50 years, the prevalence ratio for blue-yellow defects was 2.17 (95% CI: 1.03, 4.56) in the highest quartile of nonhexane solvent exposure and 1.62 (95% CI: 0.97, 2.72) in the highest category of exposure to hexane with acetone coexposure. Cumulative exposures to hexane and nonhexane solvents in the highest exposure categories were associated with elevated prevalence ratios for color vision defects in younger participants.

In this work, an apparatus for density measurements in the compressed liquid regions is presented. This installation is based on the use of a DMA HP density measuring cell and a DMA 5000 densimeter (both instruments are products of Anton Paar, Gratz, Austria). Calibration of the DMA HP cell was performed by applying the classical method in which a vacuum, water and n-decane were recommended to be used as calibration fluids. To test the capabilities of the set-up, the densities of n-hexane, toluene and dichloromethane were measured in the temperature interval 288.15 to 413.15 K and the pressure range 0.1-60 MPa. The obtained results were compared with the corresponding values found in the literature. Depending on the literature selected for comparison (the temperature and pressure ranges available), the average absolute percentage deviations were for n-hexane, 0.03-0.10 %; for toluene, 0.04-0.08 % and for dichloromethane, 0.02-0.03 %. A deeper insight into the results of this work showed that most of them were in good agreement with the literature values; higher discrepancies were evidenced in the vicinity of the ends of the temperature and pressure ranges.

Densities data of n-hexane, toluene and dichloromethane at temperatures 288.15-413.15 K and at pressures 0.1-60 MPa, determined in a previous article, were fitted to the modified Tait equation of state. The fitted temperature-pressure dependent density data were used to calculate the following derived properties: the isothermal compressibility, the isobaric thermal expansivity, the difference between specific heat capacity at constant pressure and at constant volume and the internal pressure, over the entire temperature and pressure intervals specified above. In order to assess the proposed modeling procedure, the obtained values for the isothermal compressibility and the isobaric thermal expansivity were compared with the corresponding literature data. The average absolute percentage deviations for the isothermal compressibility were for n-hexane 2.01-3.64 %, for toluene 0.64-2.48 % and for dichloromethane 1.81-3.20 %, and for the isobaric thermal expansivity, they were for n-hexane 1.31-4.17 %, for toluene 0.71-2.45 % and for dichloromethane 1.16-1.61 %. By comparing the obtained deviations values with those found in the literature, it could be concluded that the presented results agree well with the literature data.

In this work, an apparatus for density measurements in the compressed liquid regions is presented. This installation is based on the use of a DMA HP density measuring cell and a DMA 5000 densimeter (both instruments are products of Anton Paar, Gratz, Austria). Calibration of the DMA HP cell was performed by applying the classical method in which a vacuum, water and n-decane were recommended to be used as calibration fluids. To test the capabilities of the set-up, the densities of n-hexane, toluene and dichloromethane were measured in the temperature interval 288.15 to 413.15 K and the pressure range 0.1-60 MPa. The obtained results were compared with the corresponding values found in the literature. Depending on the literature selected for comparison (the temperature and pressure ranges available), the average absolute percentage deviations were for n-hexane, 0.03-0.10 %; for toluene, 0.04-0.08 % and for dichloromethane, 0.02-0.03 %. A deeper insight into the results of this work showed that most of them were in good agreement with the literature values; higher discrepancies were evidenced in the vicinity of the ends of the temperature and pressure ranges.

Densities data of n-hexane, toluene and dichloromethane at temperatures 288.15-413.15 K and at pressures 0.1-60 MPa, determined in a previous article, were fitted to the modified Tait equation of state. The fitted temperature-pressure dependent density data were used to calculate the following derived properties: the isothermal compressibility, the isobaric thermal expansivity, the difference between specific heat capacity at constant pressure and at constant volume and the internal pressure, over the entire temperature and pressure intervals specified above. In order to assess the proposed modeling procedure, the obtained values for the isothermal compressibility and the isobaric thermal expansivity were compared with the corresponding literature data. The average absolute percentage deviations for the isothermal compressibility were for n-hexane 2.01-3.64 %, for toluene 0.64-2.48 % and for dichloromethane 1.81-3.20 %, and for the isobaric thermal expansivity, they were for n-hexane 1.31-4.17 %, for toluene 0.71-2.45 % and for dichloromethane 1.16-1.61 %. By comparing the obtained deviations values with those found in the literature, it could be concluded that the presented results agree well with the literature data.

The current study discusses the structure, mechanical and transport properties of polyethylene-based materials into two parts. The first part deals with the migration and chemical depletion of active substance such as insecticides from moulded polyethylene sheets. Deltamethrin (DM) and synergist piperonyl butoxide (PBO) are often used for insect control purpose. It was found that DM as a powder was incapable of recrystallization and remained in liquid state after cooling to room temperature, and that the evaporation of a DM/PBO solution was greater than that predicted from the evaporation rates of pristine separate material components. Infrared spectroscopy and liquid chromatography showed that the loss of DM and PBO through polyethylene sheets was negligible over 30 days, when aged in air at 80 °C (60 and 80 %RH). However, significant migration of the active species was observed in aged polyethylene sheets which were exposed in liquid water (at 80 and 95 °C). In the second part, the structure and properties of multi–layered polymer films were studied in terms of crystallization kinetics, mechanical and transport properties. Previously, it has been shown that when the layer thickness decreases from micrometre-scale to nanometre-scale, leading to improvement of the film performance such as crack propagation and oxygen barrier properties. In this work, two multi-layered systems were considered based on compatible (i) or incompatible layers (ii). In the first case (i), metallocene polyethylene (mPE) and low-density polyethylene (LDPE) where investigated as 2, 24, and 288 adjacent layers. In the second case (ii) poly(ethylene-co-vinyl alcohol) (EVOH) and polyethylene adhesive was evaluated as 5 and 19 layers. The crystallization kinetic studies showed that the crystallization rate was retarded as the layers became thinner with increasing number of layers in the multi-layered films as compared to the reference films (2 and 5 layers). The observation was suggested to stem, QC 20140312

The current study discusses the structure, mechanical and transport properties of polyethylene-based materials into two parts. The first part deals with the migration and chemical depletion of active substance such as insecticides from moulded polyethylene sheets. Deltamethrin (DM) and synergist piperonyl butoxide (PBO) are often used for insect control purpose. It was found that DM as a powder was incapable of recrystallization and remained in liquid state after cooling to room temperature, and that the evaporation of a DM/PBO solution was greater than that predicted from the evaporation rates of pristine separate material components. Infrared spectroscopy and liquid chromatography showed that the loss of DM and PBO through polyethylene sheets was negligible over 30 days, when aged in air at 80 °C (60 and 80 %RH). However, significant migration of the active species was observed in aged polyethylene sheets which were exposed in liquid water (at 80 and 95 °C). In the second part, the structure and properties of multi–layered polymer films were studied in terms of crystallization kinetics, mechanical and transport properties. Previously, it has been shown that when the layer thickness decreases from micrometre-scale to nanometre-scale, leading to improvement of the film performance such as crack propagation and oxygen barrier properties. In this work, two multi-layered systems were considered based on compatible (i) or incompatible layers (ii). In the first case (i), metallocene polyethylene (mPE) and low-density polyethylene (LDPE) where investigated as 2, 24, and 288 adjacent layers. In the second case (ii) poly(ethylene-co-vinyl alcohol) (EVOH) and polyethylene adhesive was evaluated as 5 and 19 layers. The crystallization kinetic studies showed that the crystallization rate was retarded as the layers became thinner with increasing number of layers in the multi-layered films as compared to the reference films (2 and 5 layers). The observation was suggested to stem, QC 20140312

Reaction of the deprotonated N-thiophosphorylated thiourea (4′-benzo-15-crown-5)NHC(S)NHP(S)(OiPr) 2 (HL) with NiCl 2 in aqueous EtOH leads to dark green [Ni(L-1,5-S,S′) 2]·2H 2O crystals that were isolated by recrystallization from a mixture of CH 2Cl 2 and n-hexane. © 2012 The Royal Society of Chemistry.

Isothermal liquid–liquid equilibria were measured for the water–n-butanol–n-hexane system at 313.15 K. Isobaric vapor–liquid (VLE) and vapor–liquid–liquid equilibria (VLLE) were measured for the same system at normal atmospheric pressure using an all-glass dynamic recirculating still with an ultrasonic homogenizer coupled to the boiling flask. The experimental LLE, VLE and VLLE data were found to be thermodynamically consistent. The data was correlated using the NRTL and UNIQUAC models and predicted by means of UNIFAC. The parameters set thus obtained reproduces the LLE experimental data appropriately. However, it has been difficult to correlate the VLLE data and only the NRTL model produces an acceptable solution.

The deep oxidation of n-hexane was studied over Pt catalysts with small and large Pt crystallites, promoted by MnOx. The Mn was deposited on the Pt/Al2O3 by deposition-precipitation method using two alkalis, ammonia and dimethylamine. The strength of the base influenced morphology and performances of Mn-Pt catalysts. Ammonia formed mostly spherical structure of manganese oxide, while dimethylamine created fibrous needle-like shape of MnOx, typical for cryptomelane phase of manganese oxide. This was confirmed by XPS results that show an oxidation state of Mn close to that for cryptomelane. The Pt-Mn catalysts were more active than catalysts containing Pt only. Promoting effect of MnOx is more pronounced for larger Pt crystallites. Among Pt-Mn samples, catalysts synthesized with dimethylamine exhibited the highest activities. Mobility and reactivity of oxygen from Pt-O-Mn sites associated with cryptomelane phase may be responsible for increased activity.

An analysis of the evaporation process of n-hexadecane in a thermogravimetric apparatus was carried out. n-Hexadecane represents a typical example of a high boiling point compound and its study is interesting for understanding those processes where vaporization takes place in parallel with pyrolysis during thermal treatment. The process has been studied under different operating conditions: nitrogen and air atmospheres, and isothermal and dynamic runs with three different heating rates from 5 K/min to 20 K/min. The experimental data were satisfactorily correlated to a n-order model with zero process order and the same apparent activation energy for all runs, but the exponential factors of the different runs depended on the initial mass and the heating rate. The experimental results were compared with those predicted considering the diffusion process inside the crucible, taking into account the vapor pressure and the diffusion coefficient of n-hexadecane. A parameter, product of these two variables, can be estimated from a single TG run, so the vaporization process in other equipment and/or operating conditions can also be estimated.

An analysis of the evaporation process of n-hexadecane in a thermogravimetric apparatus was carried out. n-Hexadecane represents a typical example of a high boiling point compound and its study is interesting for understanding those processes where vaporization takes place in parallel with pyrolysis during thermal treatment. The process has been studied under different operating conditions: nitrogen and air atmospheres, and isothermal and dynamic runs with three different heating rates from 5 K/min to 20 K/min. The experimental data were satisfactorily correlated to a n-order model with zero process order and the same apparent activation energy for all runs, but the exponential factors of the different runs depended on the initial mass and the heating rate. The experimental results were compared with those predicted considering the diffusion process inside the crucible, taking into account the vapor pressure and the diffusion coefficient of n-hexadecane. A parameter, product of these two variables, can be estimated from a single TG run, so the vaporization process in other equipment and/or operating conditions can also be estimated.

The deep oxidation of n-hexane was studied over Pt catalysts with small and large Pt crystallites, promoted by MnOx. The Mn was deposited on the Pt/Al2O3 by deposition-precipitation method using two alkalis, ammonia and dimethylamine. The strength of the base influenced morphology and performances of Mn-Pt catalysts. Ammonia formed mostly spherical structure of manganese oxide, while dimethylamine created fibrous needle-like shape of MnOx, typical for cryptomelane phase of manganese oxide. This was confirmed by XPS results that show an oxidation state of Mn close to that for cryptomelane. The Pt-Mn catalysts were more active than catalysts containing Pt only. Promoting effect of MnOx is more pronounced for larger Pt crystallites. Among Pt-Mn samples, catalysts synthesized with dimethylamine exhibited the highest activities. Mobility and reactivity of oxygen from Pt-O-Mn sites associated with cryptomelane phase may be responsible for increased activity.

Tato práce zahrnuje popis nejpoužívanějších organických rozpouštědel. Hlavně se zabývá jejich fyzikálními a chemickými vlastnostmi, využití v různých odvětvích lidské činnosti a jejich toxickým působením na lidský organismus., This work includes a description of some organic solvents that are most generally applied. Especially the work deals with physical and chemical properties of organic solvents, their uses in different spheres of human activities and with their negative effects on human organism, Ústav inženýrství ochrany živ. prostředí, obhájeno

The precursor [FeIII(L)Cl] (LH2 N,N'-bis(2'-hydroxy- 3'-X-benzyliden)-1,6-diamino-3-N-hexane) is a high-spin (S 5/2) complex (with X -CH3, -O-CH3). This precursor is combined with the bridging unit [SnIV(CN)4] to yield star-shaped pentanuclear clusters, [(L-X-FeIII)4Sn(CN) 4]Cl4 57Fe-Mössbauer, 119mSn- Mössbauer, and ESR spectroscopy are used to study our samples. For X -CH3 the 57Fe-Mössbauer data show a multiple spin transition between iron(III) in the high-spin and low-spin state. Changing the functional group from X -CH3 to X -O-CH3 turns the switchability off.

Molecular dynamics simulations have been used to study diffusion of n-hexane in wholly amorphous poly(ethylene-stat-octene)s with comonomer contents ranging from 0 to 11.5 mol%. The branches in the polymer increased the specific volume by affecting the packing of the chains in the rubbery state in accordance with experimental data. The diffusion of n-hexane at penetrant concentrations between 0.5 and 9.1 wt% was simulated within time-scales between 0.1 and 0.2 μs. The penetrant diffusivity unexpectedly decreased with increasing comonomer content. The penetrant molecule motion statistics showed that systems with high comonomer content showed a greater tendency for short distance motion (over a sampling period of 3 ps) whereas the systems with lower comonomer content showed penetrant motion over longer distances. It seems that the branches retarded local chain mobility of the polymer thereby trapping the penetrant molecules. All systems studied showed a minimum in penetrant diffusivity at ca. 1 wt% n-hexane and a marked increase in diffusivity at higher penetrant concentrations. The volumetric data for the different polymer–penetrant systems were consonant with additional volumes of the different components. Comparison between simulated diffusivities (for a wholly amorphous polymer) and experimentally obtained diffusivity data for semicrystalline polymers showed that constraining effect of the crystals were substantial for the highly crystalline systems and that it gradually decreased with decreasing crystallinity., QC 20100909

Molecular dynamics simulations have been used to study diffusion of n-hexane in wholly amorphous poly(ethylene-stat-octene)s with comonomer contents ranging from 0 to 11.5 mol%. The branches in the polymer increased the specific volume by affecting the packing of the chains in the rubbery state in accordance with experimental data. The diffusion of n-hexane at penetrant concentrations between 0.5 and 9.1 wt% was simulated within time-scales between 0.1 and 0.2 μs. The penetrant diffusivity unexpectedly decreased with increasing comonomer content. The penetrant molecule motion statistics showed that systems with high comonomer content showed a greater tendency for short distance motion (over a sampling period of 3 ps) whereas the systems with lower comonomer content showed penetrant motion over longer distances. It seems that the branches retarded local chain mobility of the polymer thereby trapping the penetrant molecules. All systems studied showed a minimum in penetrant diffusivity at ca. 1 wt% n-hexane and a marked increase in diffusivity at higher penetrant concentrations. The volumetric data for the different polymer–penetrant systems were consonant with additional volumes of the different components. Comparison between simulated diffusivities (for a wholly amorphous polymer) and experimentally obtained diffusivity data for semicrystalline polymers showed that constraining effect of the crystals were substantial for the highly crystalline systems and that it gradually decreased with decreasing crystallinity., QC 20100909

The influence of low loadings of MnOx on the catalytic activity for n-hexene and CO oxidation over highly dispersed Pt on alumina catalysts has been investigated. The applied deposition-precipitation method allows Mn to be deposited on the Pt containing egg-shell volume. The catalyst samples were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and selective CO chemisorption. Platinum influences the dispersion of deposited MnOx. The dispersion of the MnOx phase is higher on Pt containing samples than on Al2O3. The Pt decoration by Mn is reflected by a low CO uptake and the Pt oxidation state (Pt2+). The addition of Mn lowers the catalytic activity for CO oxidation. This is attributed to a change of the Pt sites such that adsorption of CO is less favorable. The activity of the catalysts in the oxidation of n-hexane showed a significant improvement with addition of MnOx. A light-off shift by about 40 degrees C was observed. This improvement is attributed to the formation of Mn-Pt oxide like species that primarily weakens the Pt-O bond.

The influence of low loadings of MnOx on the catalytic activity for n-hexene and CO oxidation over highly dispersed Pt on alumina catalysts has been investigated. The applied deposition-precipitation method allows Mn to be deposited on the Pt containing egg-shell volume. The catalyst samples were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and selective CO chemisorption. Platinum influences the dispersion of deposited MnOx. The dispersion of the MnOx phase is higher on Pt containing samples than on Al2O3. The Pt decoration by Mn is reflected by a low CO uptake and the Pt oxidation state (Pt2+). The addition of Mn lowers the catalytic activity for CO oxidation. This is attributed to a change of the Pt sites such that adsorption of CO is less favorable. The activity of the catalysts in the oxidation of n-hexane showed a significant improvement with addition of MnOx. A light-off shift by about 40 degrees C was observed. This improvement is attributed to the formation of Mn-Pt oxide like species that primarily weakens the Pt-O bond.

In this work, room temperature interaction of n-hexane with HZSM-5 (Si/Al=20) and ion-exchanged samples containing one (CuZSM-5, FeZSM-5 and MnZSM-5) or two transition-metal cations (Fe,CuZSM-5; Cu,MnZSM-5 and Fe,MnZSM-5) was studied by microcalorimetry and TPD methods. Both differential heats and the amounts of n-hexane adsorbed per one unit cell were quantitatively determined. Higher heats of adsorption and higher amounts of adsorbed gas were found for ion-exchanged samples than for HZSM-5. The experiments of n-hexane adsorption on hydrated samples were also performed. The amounts of n-hexane adsorbed on hydrated ZSM-5 were lower in comparison with dehydrated samples, while the energies of interaction were similar.

La réalisation de ce projet fut séparée en trois grandes étapes distinctes. La première provient du fait que la résolution de nombreux problèmes techniques est inhérente à la conceptualisation et à la construction de tout nouvel appareil. Les réglages de l'appareil deviennent donc une part importante de la réalisation du projet. Ceux-ci seront présentés lors de la description de l'appareil qui se fera dans l'ordre chronologique de la réalisation d'une expérience type. La deuxième étape fut la réalisation d'un modèle simple décrivant les phénomènes physiques survenant lors de l'expérience. Ce modèle permet de mieux comprendre le type de résultats obtenus. La dernière étape fut la prise de mesures à l'aide du nouvel appareil. Deux molécules furent choisies afin d'effectuer ces tests. La première molécule étudiée est le n-hexane. Une résonance y a été détectée autour de 10 eV. Celle-ci correspond à l'attachement dissociatif menant à la dissociation d'un ion H[indice supérieur -]. La deuxième molécule est le CO[indice inférieur 2]."--Résumé abrégé par UMI.

In this work, the free energy changes and entropy changes of adsorption of n-hexane on zeolites of the MxNa87-2xX (M=Co,Ni,Zn,Cd) type were determined using their isosteric sorption heats. It was found that the exchange of Na ions in NaX with bivalent cations (Co, Ni, Zn, Cd) significantly alters the adsorption characteristics of NaX zeolite. The free energy changes and entropy changes of n-hexane adsorption were dependent on the surface coverage and on the nature of the charge-balancing cation. The specific influence of the exchanged cations on the free energy changes and entropy changes of sorption of n-hexane originates from the size, location and electronic configuration of the cation., U ovom radu su određene promene slobodne energije i promena entropije adsorpcije n-heksana na zeolitima tipa MxNa87-2xX (M=Co,Ni,Zn,Cd) na osnovu izosternih toplota sorpcije. Pokazano je da izmena Na+ jona u NaX zeolitu dvovalentnim katjonima (Co,Ni,Zn,Cd) značajno menja adsorpcione karakteristike NaX zeolita. Takođe je utvrđeno da promena slobodne energije i promena entropije adsorpcije n-heksana zavisi i od stepena pokrivenosti površine zeolita.

The kinetics of n-hexane and toluene complete oxidation has been studied over 0.12% Pt/Al 2 O 3 catalysts. Measurements were performed in an external recycle reactor. Reaction rates were measured as a function of temperature and reactants concentrations for two platinum crystallite sizes, 1.0 and 15.5 nm. The turnover frequency (TOF) for the oxidation of both hydrocarbons is about 10 times higher for the 15.5 nm than for the 1.0 nm Pt crystallite size. The reaction constants are calculated according to Mars van Krevelen (MVK) mechanism. The oxygen chemisorption rate constant (k O ) is the same during the n-hexane and the toluene oxidation for each sizes of platinum crystallite. For both hydrocarbons the oxygen chemisorption rate constant and the surface reaction rate constant (k i ) are higher for 15.5 nm than for 1.0 nm crystallite size. The activation energy for k O decreases with the increase of the Pt crystallite size. The activation energy for k i is independent on the Pt crystallite size for both hydrocarbons. The values of kinetic constants reveal that the increase of the reaction rate for large Pt crystallites could be related to the lower activation energy for k O . This implies that on large Pt crystallites oxygen is held on Pt atoms with a lower bond strength that on small Pt crystallites, which explains the structure sensitivity found for n-hexane and toluene oxidation.

The oxidation of n-hexane and toluene mixtures in air over Pt/Al2O3 catalysts with mean Pt crystallite sizes of 1.0 and 15.5 nm has been studied. Measurements were performed in an external recycle reactor at temperatures in the range of 120–181 °C, in a concentration range of one hydrocarbon from 500 to 10,000 ppm. The mutual inhibition of the oxidation activity of n-hexane and toluene in the mixtures was observed for both Pt crystallite sizes. The structure sensitivity previously established for the oxidation of single components remains valid for their mixture. The mixture model oxidation based on a Mars van Krevelen mechanism fits very well experimental data at lower temperatures (for n-hexane: 148–160 °C; for toluene: 120–140 °C), whereas at higher temperatures the model predicts higher values for catalysts with both Pt crystallite sizes. The mixture model based on equilibrium adsorption of hydrocarbons and strong adsorption of oxygen fits exceptionally well experimental data in the whole investigated temperature range. For catalysts with a mean Pt crystallite size of 1.0 nm the evaluated ratio of adsorption coefficients of n-hexane and toluene is 9, and for the catalysts with a mean Pt crystallite size of 15.5 nm the ratio is 0.13. The evaluated ratios of adsorption coefficients point out that n-hexane is more strongly bound than toluene for catalysts with smaller Pt crystallites, while at larger Pt crystallites toluene is more strongly adsorbed than n-hexane.

In this work, the possibility of obtaining selective membranes for water and hydrophobic liquids by plasma enhanced chemical vapor deposition (PECVD) of hexamethyldisilazane (HMDS) or double layers of HMDS and n-hexane on porous substrates using a capacitive plasma reactor was investigated. The porous substrates used were paper filter, diatomite and polyester textiles. The films were characterized by X-ray photoelectron spectroscopy (XPS), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and contact angle measurements. The membranes obtained were characterized by the Cobb test. Their efficiency to separate hydrocarbon compounds from water was evaluated through filtration experiments and Karl–Fischer titration tests. The reagents used in the filtration experiments were: chloroform, n-hexane, n-heptane, ethyl ether, benzene and diesel. XPS analysis showed that Si, N, C and O were present at the surface of the film. C peak was dominant in the double layer film spectra. C–Hn, CH2, Si–H, Si–CH3, N–H, Si–CH2–Si, Si–N–Si and Si–C bonds were identified in both types of the films by ATR-FTIR. The relative intensities of the corresponding peaks in the two spectra were different. The XPS and FTIR results indicated that C was most likely present in a CHn form at the surface of double layer film. The average contact angles formed by drops of water on the film surface ranged from 135° to 155°. Water adsorption measured by Cobb test decreased from average values ranging from 300 to 9000 g m−2 (for nonmodified surfaces) to values ranging from 0 to 20 g m−2 (for treated surfaces). The Karl–Fischer titration indicated that between 90 and 1000 ppm (depending on the reagent used) of water remained in the hydrocarbon compound after filtration.

The kinetics of n-hexane and toluene complete oxidation has been studied over 0.12% Pt/Al 2 O 3 catalysts. Measurements were performed in an external recycle reactor. Reaction rates were measured as a function of temperature and reactants concentrations for two platinum crystallite sizes, 1.0 and 15.5 nm. The turnover frequency (TOF) for the oxidation of both hydrocarbons is about 10 times higher for the 15.5 nm than for the 1.0 nm Pt crystallite size. The reaction constants are calculated according to Mars van Krevelen (MVK) mechanism. The oxygen chemisorption rate constant (k O ) is the same during the n-hexane and the toluene oxidation for each sizes of platinum crystallite. For both hydrocarbons the oxygen chemisorption rate constant and the surface reaction rate constant (k i ) are higher for 15.5 nm than for 1.0 nm crystallite size. The activation energy for k O decreases with the increase of the Pt crystallite size. The activation energy for k i is independent on the Pt crystallite size for both hydrocarbons. The values of kinetic constants reveal that the increase of the reaction rate for large Pt crystallites could be related to the lower activation energy for k O . This implies that on large Pt crystallites oxygen is held on Pt atoms with a lower bond strength that on small Pt crystallites, which explains the structure sensitivity found for n-hexane and toluene oxidation.

The oxidation of n-hexane and toluene mixtures in air over Pt/Al2O3 catalysts with mean Pt crystallite sizes of 1.0 and 15.5 nm has been studied. Measurements were performed in an external recycle reactor at temperatures in the range of 120–181 °C, in a concentration range of one hydrocarbon from 500 to 10,000 ppm. The mutual inhibition of the oxidation activity of n-hexane and toluene in the mixtures was observed for both Pt crystallite sizes. The structure sensitivity previously established for the oxidation of single components remains valid for their mixture. The mixture model oxidation based on a Mars van Krevelen mechanism fits very well experimental data at lower temperatures (for n-hexane: 148–160 °C; for toluene: 120–140 °C), whereas at higher temperatures the model predicts higher values for catalysts with both Pt crystallite sizes. The mixture model based on equilibrium adsorption of hydrocarbons and strong adsorption of oxygen fits exceptionally well experimental data in the whole investigated temperature range. For catalysts with a mean Pt crystallite size of 1.0 nm the evaluated ratio of adsorption coefficients of n-hexane and toluene is 9, and for the catalysts with a mean Pt crystallite size of 15.5 nm the ratio is 0.13. The evaluated ratios of adsorption coefficients point out that n-hexane is more strongly bound than toluene for catalysts with smaller Pt crystallites, while at larger Pt crystallites toluene is more strongly adsorbed than n-hexane.

The importance of the isoform CYP2E1 of the human cytochrome P-450 superfamily of enzymes for occupational and environmental medicine is derived from its unique substrate spectrum that includes a number of highly important high-production chemicals, such as aliphatic and aromatic hydrocarbons, solvents and industrial monomers (i.a. alkanes, alkenes, aromatic and halogenated hydrocarbons). Many polymorphic genes, such as CYP2E1, show considerable differences in allelic distribution between different human populations. The polymorphic nature of the human CYP2E1 gene is significant for inter-individual differences in toxicity of its substrates. Since the substrate spectrum of CYP2E1 includes many compounds of basic relevance to industrial toxicology, a rationale for metabolic interactions of different CYP2E1 substrates is provided. In-depth research into the inter-individual phenotypic differences of human CYP2E1 enzyme activities was enabled by the recognition that the 6-hydroxylation of the drug chlorzoxazone is mediated by CYP2E1. Studies on CYP2E1 phenotyping have pointed to inter-individual variations in enzyme activities. There are consistent ethnic differences in CYP2E1 enzyme expression, mostly demonstrated between European and Japanese populations, which point to a major impact of genetic factors. The most frequently studied genetic polymorphisms are the restriction fragment length polymorphisms PstI/RsaI (mutant allele: CYP2E1*5B) located in the 5′-flanking region of the gene, as well as the DraI polymorphism (mutant allele: CYP2E1*6) located in intron 6. These polymorphisms are partly related, as they form the common allele designated CYP2E1*5A. Striking inter-ethnic differences between Europeans and Asians appear with respect to the frequencies of the CYP2E1*5A allele (only approximately 5% of Europeans are heterozygous, but 37% of Asians are, whilst 6% of Asians are homozygous). Available studies indicate a wide variation in human CYP2E1 expression, which