The demand for hydrogen as a clean energy carrier has increased greatly. The Cu-Cl cycle is a promising thermochemical cycle that is currently being developed to be the large-scale method of hydrogen production. The lifetime of materials for the pipes transporting molten CuCl is an important parameter for an economic design of a commercial thermochemical Cu-Cl hydrogen plant. This research is an examination of candidate materials following an immersion test in molten CuCl at 500 °C for 100 h. Two alloys, Ni based super-alloy (Inconel 625) and super austenitic stainless steel (AL6XN) were selected as the base metal. There were two types of coating applied to improve the corrosion resistance of the base metals during molten CuCl exposure. A metallic of Diamalloy 4006 and two ceramic of yttria stabilized zirconia and alumina coatings were applied to the base metal using thermal spray methods. An immersion apparatus was designed and constructed to perform an immersion test that has a condition similar to those in a hydrogen plant. After the immersion test, the materials were evaluated using an electrochemical method in combination with ex-situ surface analysis. The surface condition including elemental composition, film structure and resistivity of the materials were examined and compared. The majority of the coatings were damaged and fell off. Cracks were found in the original coated specimens indicating the sample geometry may have affected the integrity of the sprayed coating. When the coating cracked, it provided a pathway for the molten CuCl to go under the coating and react with the surface underneath the coating. Copper deposits and iron chloride that were found on the sample surfaces suggest that there were corrosion reactions that involved the metal dissolution and reduction of copper during immersion test. The results also suggest that Inconel 625 performed better than stainless steel AL6XN. Both Diamalloy 4006 and YSZ (ZrO2 18TiO2 10Y2O3) coatings seemed to provide better protection to the underlying base metal than alumina (Al2O3 3TiO2) coating. / UOIT

The Cu-Cl thermochemical cycle is a promising method to generate hydrogen as a clean fuel for human use in the future. The cycle can be coupled to nuclear reactors to supply its heat requirements. The cycle generates hydrogen by splitting water molecules through a series of chemical reactions. Thermal management within the cycle is crucial for improving its thermal efficiency. The cycle has an average theoretical efficiency of around 46% without any heat recovery. The efficiency may increase up to 74%, if all heat associated with the products of the cycle’s steps is recycled internally. The products of the different processes that transfer heat are; oxygen, hydrogen, and molten CuCl. The heat carried by oxygen and hydrogen can be recovered by the use of conventional heat exchangers. However, recovering heat from molten CuCl is very challenging due to the phase transformations that molten CuCl undergoes, as it cools down from liquid to solid states. This thesis presents a new model that predicts the fluid flow and heat transfer in a direct contact heat exchanger, designed to recover the heat from molten CuCl, through the physical interaction between CuCl droplets and air. Numerical results for the variations of temperature, velocity, heat transfer rate, and so forth, are given for two cases of CuCl flow. The predicted dimensions of the heat exchanger were found to be a diameter of 0.13 m, and a height of 0.6 and 0.8 m for 1 and 0.5 mm droplet diameters, respectively. The results obtained provide valuable insights for the equipment design and scale-up of the Cu-Cl cycle. / UOIT

Submitted by Raquel Riciati do Couto Vilela null (r.vilela@ymail.com) on 2017-05-10T19:43:47Z No. of bitstreams: 1 Dissertação final - Raquel Vilela.pdf: 4751160 bytes, checksum: fa0956e5e393b6c5ddea05d45779ce6b (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-05-10T19:46:51Z (GMT) No. of bitstreams: 1 vilela_rrc_me_rcla.pdf: 4751160 bytes, checksum: fa0956e5e393b6c5ddea05d45779ce6b (MD5) / Made available in DSpace on 2017-05-10T19:46:51Z (GMT). No. of bitstreams: 1 vilela_rrc_me_rcla.pdf: 4751160 bytes, checksum: fa0956e5e393b6c5ddea05d45779ce6b (MD5) Previous issue date: 2017-03-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A incorporação de nanopartı́culas em matrizes hı́bridas produz materiais com grande potencial para aplicações em diversas áreas de estudo. Na óptica, sua funcionalidade surge quando elétrons confinados em estruturas tridimensionais nanométricas são excitados. Em princı́pio, esses materiais exibem nı́vel de energia discreto, apresentando picos estreitos no espectro de absorção. Tal comportamento torna-os atrativos para óptica não-linear e aplicações eletro-ópticas. Neste trabalho, o processo sol-gel foi utilizado para a sı́ntese de nanocompósitos contendo CuCl ou CuBr. Cu2O, HBr e HCl foram utilizados como precursores para os CuBr e CuCl, e a matriz Orgânica/Sı́lica foi preparada a partir dos alcóxidos 3-glicidoxipropiltrimetoxisilano (GPTS) e Tetraetilortosilicato (TEOS). As amostras foram preparadas na forma de filmes finos depositados sobre lâminas de vidro, utilizando a técnica Dip-Coating. Após a secagem, as amostras foram tratadas num forno convencional e/ou expostas à radiação UV utilizando uma luz negra comercial. A espectroscopia de absorção UV-VIS permitiu identificar estreitas bandas de absorção, bem como sua variação. O espectro de absorção (UV-VIS) registrou à temperatura ambiente picos em 418 e 399 nm para as nanopartı́culas de CuBr e a 376 e 380 nm para as nanopartı́culas CuCl, correspondente aos excitons Z1,2 e Z3 respectivamente. Comportamento semelhante foi relatado na literatura. / The incorporation of nanoparticles in hybrid matrices has produced materials with great potential for applications in many fields of study. In optics, its functionality arises when electrons confined in nanometric three-dimensional structures are excited. At first, these materials exhibit discrete energy level, with sharp peaks in the absorption spectrum. Such behavior makes them attractive to non-linear optical and electro-optical applications. In this work, the sol-gel process was used for the synthesis of nanocomposite containing CuCl or CuBr. These complexes decompose during thermal or ultraviolet treatment, and form copper halide nanoparticles. Cu2O, HCl and HBr were used as precursors for the CuBr and CuCl, and the organic matrix/silica was prepared from alkoxides of 3-glycidoxypropyltrimethoxysilane (GPTS) and tetraethylorthosilicate (TEOS). The samples were made in the form of thin films deposited on glass slides using the dip-coating technique. After drying, they were treated in a conventional oven and/or exposed to UV radiation using a commercial black light. The UV-VIS absorption spectrum allowed to identify narrow absorption bands, such as its variation. The absorption spectrum (UV-Vis) recorded at room temperature showed peaks at 418 and 399 nm CuBr nanoparticles and 376 and 380 to CuCl nanoparticles corresponding to the excitons Z1,2 and Z3 respectively. Similar behavior has been reported in the literature.

HCl ist ein Nebenprodukt bei vielen organischen Chlorierungsprozessen. Die Aufarbeitung von HCl wäre wirtschaftlich sinnvoll. Eine der möglichen Optionen ist die Rückgewinnung des Chlors durch die katalytische HCl-Oxidation mit O2 (Deacon-Prozess). Das Hauptziel dieser Arbeit war es, die katalytische Aktivität von kupferchlorid-haltigen Schmelzen in Abhängigkeit von der Temperatur und dem Verhältnis der Reaktionsgase zu untersuchen. Dazu wurden Versuche unter stationären und instationären Reaktionsbedingungen im Temperaturintervall zwischen 400 und 500 °C durchgeführt. Für das bessere Verständnis des Katalysator-Systems wurde ein thermodynamisches Modell für das Stoffsystem MeCl-CuCl-CuCl2-CuO-HCl-H2O-Cl2-O2 (Me = Li, Na, K) erstellt. Weiterhin wurden mithilfe von kinetischen Untersuchungen Hinweise auf die Rolle der gelösten oxidischen Zwischenverbindungen im stufenweisen Reaktionsmechanismus gefunden. Mit den Versuchsergebnissen wurde gezeigt, dass die MeCl-CuCl-CuCl2-Schmelzen eine genügende katalytische Aktivität besitzen und damit eine Alternative zu den mit Feststoffträgern arbeitenden Katalysatoren darstellen. Zur Minderung von Korrosionsproblemen wurden mehrstufige Prozessführungen kritisch diskutiert.

Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-11-22T21:08:35Z No. of bitstreams: 1 SuzanaAraujoBarbosa_TESE.pdf: 16716381 bytes, checksum: 89faa5fab90c18454c05e07a0fe96e3e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-11-24T21:58:01Z (GMT) No. of bitstreams: 1 SuzanaAraujoBarbosa_TESE.pdf: 16716381 bytes, checksum: 89faa5fab90c18454c05e07a0fe96e3e (MD5) / Made available in DSpace on 2017-11-24T21:58:01Z (GMT). No. of bitstreams: 1 SuzanaAraujoBarbosa_TESE.pdf: 16716381 bytes, checksum: 89faa5fab90c18454c05e07a0fe96e3e (MD5) Previous issue date: 2017-08-28 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Neste trabalho apresenta-se um estudo, de cunho experimental, de nanopart?culas cristalinas n?o agregadas e monodispersas de tr?s sistemas a base de Ni e/ou Cu, produzidas a partir do m?todo sol-gel e com o aux?lio do pol?mero quitosana. O primeiro sistema ? um nanocomp?sito com di?metro m?dio de 9-27 nm. As amostras cont?m principalmente a fase de Ni e as fases ? e ? do hidreto de n?quel (NiH). A fase ?-NiH apresentou uma contribui??o magn?tica significativa para T<50 K, e os hidretos mostraram-se quimicamente est?veis ao longo de v?rios meses. O segundo sistema tem fase ?nica e referente ao semicondutor i?nico Cu(I)Cl com part?culas esf?ricas de di?metro m?dio de 9 nm. O terceiro sistema consiste na solu??o s?lida de ?tomos de Ni e Cu, e suas amostras cont?m v?rias fases de ligas de NixCu(1-x) para 0,50<x<0,92, com di?metros m?dios na faixa de 11-90 nm. Os resultados de microscopia eletr?nica de transmiss?o sugerem que as fases ricas em Cu est?o dispostas nos contornos das part?culas, enquanto os centros das mesmas parecem ser ricos em Ni. Nas medidas magn?ticas para 300<T<800 K percebeu-se mudan?as na magnetiza??o relacionadas com as transi??es magn?ticas das ligas com 75<x<92. Para temperaturas abaixo da transi??o de Curie (Tc) da liga Ni92Cu8 foi verificado um aumento do sinal magn?tico devido ? fase de Hopkinson. J? para T>Tc foi observada a forma??o da fase de Griffiths, a qual ? devida a clusters de Ni que se encontram dispersos num ambiente rico em Cu. Os par?metros cr?ticos obtidos para esta fase est?o de acordo com a literatura. As an?lises das curvas de histerese revelam uma constante de anisotropia magnetocristalina efetiva (Keff) maior que a constante K1 do Ni puro e esse resultado foi atribu?do a contribui??es de anisotropia de superf?cie. A fase de Griffiths e o valor aumentado de Keff devem ter sua origem nas fases ricas em Cu, na periferia das nanopart?culas. Experimentos de aquecimento das amostras em presen?a de campo magn?tico AC mostraram taxas de absor??o espec?ficas com valores crescentes de acordo com o teor de Ni. A m?xima varia??o de temperatura ocorreu em 200 s, indicando que tais ligas podem ser usadas em hipertermia magn?tica para o tratamento de c?nceres.

HCl ist ein Nebenprodukt bei vielen organischen Chlorierungsprozessen. Die Aufarbeitung von HCl wäre wirtschaftlich sinnvoll. Eine der möglichen Optionen ist die Rückgewinnung des Chlors durch die katalytische HCl-Oxidation mit O2 (Deacon-Prozess). Das Hauptziel dieser Arbeit war es, die katalytische Aktivität von kupferchlorid-haltigen Schmelzen in Abhängigkeit von der Temperatur und dem Verhältnis der Reaktionsgase zu untersuchen. Dazu wurden Versuche unter stationären und instationären Reaktionsbedingungen im Temperaturintervall zwischen 400 und 500 °C durchgeführt. Für das bessere Verständnis des Katalysator-Systems wurde ein thermodynamisches Modell für das Stoffsystem MeCl-CuCl-CuCl2-CuO-HCl-H2O-Cl2-O2 (Me = Li, Na, K) erstellt. Weiterhin wurden mithilfe von kinetischen Untersuchungen Hinweise auf die Rolle der gelösten oxidischen Zwischenverbindungen im stufenweisen Reaktionsmechanismus gefunden. Mit den Versuchsergebnissen wurde gezeigt, dass die MeCl-CuCl-CuCl2-Schmelzen eine genügende katalytische Aktivität besitzen und damit eine Alternative zu den mit Feststoffträgern arbeitenden Katalysatoren darstellen. Zur Minderung von Korrosionsproblemen wurden mehrstufige Prozessführungen kritisch diskutiert.:1 Einleitung. . . . . . . . . . .7 2 Theoretische Grundlagen zum Deacon-Prozess in Salzschmelzen. . . . . . . . . . .9 2.1 Thermochemie des Deacon-Prozesses. . . . . . . . . . .9 2.1.1 Oxidation von HCl mit O2 ohne Katalysator. . . . . . . . . . .9 2.1.2 Oxidation von HCl mit O2 in Gegenwart von CuCl2-haltigen Katalysatoren. . . . . . . . . . .10 2.2 Kinetik der Teilreaktionen in kupferchlorid-haltigen Salzschmelzen. . . . . . . . . . .13 2.2.1 Zersetzung des CuCl2. . . . . . . . . . .14 2.2.2 Oxidation von CuCl. . . . . . . . . . .15 2.2.3 Reaktion zwischen CuO-haltiger Schmelze und Chlorwasserstoff. . . . . . . . . . .17 3 Thermodynamische Modellierung der Mischungen aus LiCl, NaCl, KCl, CuCl und CuCl2. . . . . . . . . . .19 3.1 Thermodynamische Daten der reinen Stoffe. . . . . . . . . . .20 3.2 Mischungsmodelle. . . . . . . . . . .22 3.3 Vorgehensweise bei der Optimierung. . . . . . . . . . .25 3.4 System LiCl-NaCl-KCl. . . . . . . . . . . 25 3.5 System LiCl-CuCl. . . . . . . . . . .26 3.6 System NaCl-CuCl. . . . . . . . . . .28 3.7 System KCl-CuCl. . . . . . . . . . .29 3.8 System LiCl-CuCl2. . . . . . . . . . .30 3.9 System NaCl-CuCl2. . . . . . . . . . .33 3.10 System KCl-CuCl2 . . . . . . . . . . .34 3.11 System CuCl-CuCl2. . . . . . . . . . . 35 3.12 Ternäre Systeme. . . . . . . . . . .39 4 Untersuchungen zur CuO-Löslichkeit und der Stabilität von Oxidchloriden des Kupfers. . . . . . . . . . .46 4.1 Präparation von Cu2OCl2 und K4Cu4OCl10. . . . . . . . . . .46 4.2 Untersuchungen zur CuO-Löslichkeit. . . . . . . . . . .47 4.2.1 Thermodynamische Reaktionsdaten. . . . . . . . . . .47 4.2.2 Auswertung der Literatur. . . . . . . . . . .48 4.2.3 O2-Titration kupferchlorid-haltiger Schmelze. . . . . . . . . . .49 4.2.4 Hochtemperatur-Filtration und CuO-Analyse. . . . . . . . . . .53 4.2.5 Thermischer Zerfall von Cu2OCl2. . . . . . . . . . .55 4.2.6 Thermischer Zerfall von K4Cu4OCl10. . . . . . . . . . .57 4.3 Thermodynamische Modellierung CuO-haltiger Systeme. . . . . . . . . . .59 4.3.1 Cu2OCl2. . . . . . . . . . .59 4.3.2 K4Cu4OCl10. . . . . . . . . . .60 4.3.3 CuO-Löslichkeit. . . . . . . . . . .62 4.3.4 Salzschmelzenmodell mit oxidhaltigen Systemen. . . . . . . . . . .63 4.4 Thermochemie des Deacon-Prozesses mit Modell-Daten. . . . . . . . . . .69 5 Experimentelle Untersuchungen zur katalytischen Oxidation von HCl in Salzschmelzen. . . . . . . . . . .72 5.1 Versuchsprogramm. . . . . . . . . . .72 5.2 Allgemeine Vorgehensweise. . . . . . . . . . .72 5.2.1 Versuchsapparatur. . . . . . . . . . .72 5.2.2 Vorbereitung der Salzmischungen. . . . . . . . . . .74 5.2.3 Bestimmung der Gaszusammensetzung und Umsatzberechnungen. . . . . . . . . . .75 5.2.4 Bestimmung der Schmelzenzusammensetzung. . . . . . . . . . .77 5.2.5 Charakteristik der Reaktoreinsätze Spirale und Fritte. . . . . . . . . . .77 5.3 Versuche mit Salzmischungen auf der Basis von Kupferchlorid. . . . . . . . . . .81 5.3.1 Stationäre Strömungsverhältnisse. . . . . . . . . . .81 5.3.2 Instationäre Bedingungen. . . . . . . . . . .95 6 Vorschläge zur Technologie. . . . . . . . . . .106 7 Zusammenfassung. . . . . . . . . . .112 Literaturverzeichnis. . . . . . . . . . .115 Anhang. . . . . . . . . . .124 A.1 Thermodynamische Standard-Daten. . . . . . . . . . .124 A.2 Thermodynamische Daten für das Modell LiCl-NaCl-KCl-CuCl-CuCl2-CuO-H2O-HCl-O2-Cl2. . . . . . . . . . .126 A.3 Charakteristika der kupferoxidhaltigen Verbindungen. . . . . . . . . . .133 A.3.1 P-XRD- und Raman-Aufnahmen der synthetischen Oxidchloriden. . . . . . . . . . .133 A.3.2 O2 -Titration kupferchlorid-haltiger Schmelze. . . . . . . . . . .134 A.3.3 Thermischer Zerfall von Cu2OCl2 und K4Cu4OCl10. . . . . . . . . . .137 A.3.4 Phasendiagramm KCl-CuCl2-CuO. . . . . . . . . . .138 A.4 Katalytische Oxidation von HCl in Salzschmelzen. . . . . . . . . . .138 A.5 Physikalische Eigenschaften von (Alk-Cl)-CuCl-CuCl Salzschmelzen. . . . . . . . . . .156 A.6 Chemikalien. . . . . . . . . . .161 A.7 Geräte, Anlagen. . . . . . . . . . .162 A.8 Methode zur titrimetrischen Bestimmung von Cu+, Cu+2 und CuO. . . . . . . . . . .164 A.9 Berechnete Chlor- und Sauerstoffpartialdrücke für (Alk-Cl)-CuCl-CuCl2-Schmelzen. . . . . . . . . . .164 A.10 Berechnete Aktivitäten der geschmolzenen Kupferchloride in (Alk-Cl)-CuCl-CuCl2-Schmelzen. . . . . . . . . . .171

The purpose of the research was to design, build, test, and recommend a process to economically separate CO from a gas mixture of CO, CO2, and O2. The general method considered in this research to accomplish the separation was liquid absorption in a packed column. Several experiments were performed to identify the best process solution to use in a prototype. The experiments, based on the COSORB process, consisted of CuCl mixed with a complexing agent (metal tri-chloride) and a solvent (metal tetra-chloride, toluene, ethanol, etc.). The best method consisted of an aqueous solution of CuCl and MgCl2, which has previously been used for CO absorption experiments reported in the literature. The absorption takes place at elevated pressure (30 psig) and ambient temperature, and the stripping occurs at approximately 75 ºC. Using the apparatus at approximate design conditions, the highest removal of CO was 88% with a product composition of 48%. The highest product composition achieved was 84%; in this case CO removal was 66%. Product composition was low because a significant amount of CO2 physically absorbed into solution (which also decreased the pH of the solution to about 4, according to calculation). The removal of CO should increase with a taller column and higher liquid flow through the column; however, this might decrease the product composition. Advantages of this process are that the raw materials used are relatively cheap, heating and cooling requirements are lower than similar processes, and operation is relatively simple.

<p>Thin films play an important role in science and technology today. By combining different materials, properties for specific applications can be optimised. In this thesis growth of copper, copper(I) oxide and copper(I) nitride on two different substrates, amorphous SiO₂ and single crystalline α-Al₂O₃ by the so called Atomic Layer Deposition (ALD) techniques has been studied. This technique allows precise control of the growth process at monolayer level on solid substrates. Other characteristic features of ALD are that it produces films with excellent step coverage and good uniformity even as extremely thin films on complicated shaped substrates.</p><p>Alternative deposition schemes were developed for the materials of interest. It was demonstrated that use of intermediate water pulses affected the deposition pathways considerably. By adding water, the films are thought to grow via formation of an oxide over-layer instead of through a direct reaction between the precursors as in the case without water.</p><p>For growth of copper(I) nitride from Cu(hfac)₂ and ammonia no film growth occurred without adding water to the growth process. The Cu₃N films could be transformed into conducting copper films by post annealing. In copper growth from CuCl and H₂ the water affected film growth on the alumina substrates considerably more than on the fused silica substrates. The existence of surface -OH and/or -NH_x groups was often found to play an important role, according to both theoretical calculations and experimental results.</p>

Thin films play an important role in science and technology today. By combining different materials, properties for specific applications can be optimised. In this thesis growth of copper, copper(I) oxide and copper(I) nitride on two different substrates, amorphous SiO2 and single crystalline α-Al2O3 by the so called Atomic Layer Deposition (ALD) techniques has been studied. This technique allows precise control of the growth process at monolayer level on solid substrates. Other characteristic features of ALD are that it produces films with excellent step coverage and good uniformity even as extremely thin films on complicated shaped substrates. Alternative deposition schemes were developed for the materials of interest. It was demonstrated that use of intermediate water pulses affected the deposition pathways considerably. By adding water, the films are thought to grow via formation of an oxide over-layer instead of through a direct reaction between the precursors as in the case without water. For growth of copper(I) nitride from Cu(hfac)2 and ammonia no film growth occurred without adding water to the growth process. The Cu3N films could be transformed into conducting copper films by post annealing. In copper growth from CuCl and H2 the water affected film growth on the alumina substrates considerably more than on the fused silica substrates. The existence of surface -OH and/or -NHx groups was often found to play an important role, according to both theoretical calculations and experimental results.

No description available.