Thesis (Ph. D.)--University of Alabama at Birmingham, 2009. / Additional advisors: Heng Ban, Chih-Hsiung Cheng, Thomas K. Gale, Melinda M. Lalor. Description based on contents viewed June 3, 2009; title from PDF t.p. Includes bibliographical references (p. 113-123).

Thesis (Ph.D.)--University of Wyoming, 2009. / Title from PDF title page (viewed on May 21, 2010). Includes bibliographical references (p. 50-63).

No description available.

Porous inorganic solids including mesoporous silicas, zeolites and silicoalumnio-phosphates have been investigated as adsorbents for carbon dioxide, particularly in relation to uptake from flue gases at 0.1 bar and ca. 298 K, but also at higher pressures. The mesoporous silicas SBA-1 and SBA-2, with mesocages separated by narrower windows, have been prepared, calcined at various temperatures and also nitrided with ammonia at high temperature. Nitridation has resulted in framework nitrogen incorporation, but this gave only small increases in the uptake of CO₂ of these mesoporous silicas, which are very low (< 0.2 mmol g⁻¹) at flue gas conditions (0.1 bar, 298 K). A series of cationic forms of the small pore zeolites, chabazite, ZK-5 and Rho, have been prepared by exhaustive cation exchange (and pre-calcination of the as-prepared form of Rho). In addition, a series of ultrastabilised zeolite Rho samples has been prepared to investigate the influence of extra-framework aluminium species on CO₂ uptake. For comparison, the silicoaluminophosphate versions of ZK-5 (SAPO STA-14) and Rho (SAPO(RHO)) have been prepared. Adsorption on Li-, Na-, K- and Ca-forms of chabazite (Si/Al = 3.0) has been related to the crystal structures of their dehydrated forms, as determined by Rietveld refinement against powder X-ray diffraction data (PXRD). For Na- and K-chabazite the structure has been measured in situ by PXRD during CO₂ adsorption. Li-chabazite has the highest uptake from all chabazite cationic forms (4.3 mmol g⁻¹). PXRD of K-chabazite reveals cation migration from eight-membered ring sites to six-membered ring sites upon CO₂ adsorption. Na-chabazite shows partial transformation from rhombohedral to monoclinic symmetry upon prolonged evacuation at high temperature, with resultant non-Type I CO₂ adsorption behaviour. Li-, Na- and K-forms of ZK-5 (Si/Al = 4.16) show high CO₂ uptakes at 0.1 bar and 298 K (Li-ZK-5, 4.7 mmol g⁻¹, which is the highest of the solids measured here). Like all H-forms, H-ZK-5 shows weaker uptake. None of the ZK-5 forms show high selectivity for CO₂ over small hydrocarbons, because cations do not block eight-membered ring windows and the structures do not distort upon dehydration. Uptake of CO₂ on univalent cation forms of zeolite Rho has been studied at low (up to 1 bar) and high (up to 10 bar) pressures. All cationic forms (but not H-Rho) show distortion (Im3̅m to I4̅3m) upon dehydration. Forms of zeolite Rho in which cations occupy window sites in the eight-membered rings between α-cages show hysteresis in their CO₂ isotherms, the magnitude of which (Na⁺,NH₄⁺ < K⁺ < Cs⁺) correlates with the tendency of cations to occupy double eight-membered ring sites rather than single eight-membered ring sites. Additionally, reversible CO₂ uptake using the Zero Length Column method on fully and partially cation exchanged samples has been measured. In situ synchrotron PXRD of CO₂ adsorption on Na-Rho indicates Na cations remain in window sites on the time average, indicating CO₂ uptake must occur by a 'trapdoor mechanism' by which Na cations move away from the windows to allow CO₂ to adsorb. In addition, in situ PXRD reveals the adsorption sites of CO₂ bound cations. Adsorption of small hydrocarbons does not occur on Rho, even at high pressure, indicating that adsorption is selective, and depends on the degree of interaction with the adsorbate rather than simply on the molecular size. Na-Rho is therefore a selective adsorbent for CO₂ over CH₄ with selectivities of 150–25 at 1–9 bar and 298 K, predicted from the single component isotherms, and an uptake of 3.07 mmol g⁻¹ at 0.1 bar. High ‘selectivities' are also observed over K-, Cs- and Ca-forms, examples of a novel type of adsorption selectivity.

D. Tech. Mechanical Engineering. / Investigates and/or rank the performance of locally available materials (i.e. limestone, dolomite, or calcrete) as sorbents in the capture of SO2 emissions from coal-fired power plants. Two experimental procedures were adopted in this work: the pH-stat method was used to simulate conditions encountered in wet flue gas desulphurisation (WFGD); and the fixed-bed reactor was used to simulate conditions encountered in the dry in-duct flue gas desulphurisation (DFGD) process. It is important to note that most studies of using calcium-based materials as sorbents for SO2 removal have been carried out in overseas countries. These studies were carried out using materials and research conditions prevailing in the particular countries. Furthermore, all South African coal-fired power stations burn low grade coal allowing the high grade coal to be exported. As a result, coal-fired power stations in South Africa emit higher emissions than the overseas power stations which are operated on high grade coals. Thus the results achieved internationally may not be directly translated to the South African conditions.

The major goals of this thesis were to: (1) create a site-isolated aminosilica material with higher amine loadings than previously reported isolation methods, (2) use spectroscopic, reactivity, and catalytic (olefin polymerization precatalysts) probes to determine isolation of amine groups on these organic/inorganic hybrid materials, (3) synthesize an organic/inorganic hybrid material capable of activating Group 4 olefin polymerization precatalysts, and (4) synthesize a high amine loaded organic/inorganic hybrid material capable of reversibly capturing CO2 in a simulated flue gas stream. The underlying motivation of this research involved the synthesis and design of novel amine and sulfonic acid materials. Traditional routes to synthesize aminosilicas have led to the formation of a high loading of multiple types of amine sites on the silica surface. Part of this research involved the creation of a new aminosilica material via a protection/deprotection method designed to prevent multiple sites, while maintaining a relatively high loading. As a characterization technique, fluorescence spectroscopy of pyrene-based fluorophores loaded on traditional aminosilicas and site-isolated aminosilicas was used to probe the degree of site-isolation obtained with these methods. Also, this protection/deprotection method was compared to other reported isolation techniques with heterogeneous Group 4 constrained-geometry inspired catalysts (CGCs). It was determined that the degree of separation of the amine sites could be controlled with protection/deprotection methods. Furthermore, an increase in the reactivity of the amines and the catalytic activity of CGCs built off of the amines was determined for aminosilicas synthesized by a protection/deprotection method. The second part of this work involved developing organic/inorganic hybrid materials as heterogeneous Brønsted acidic cocatalysts for activation of olefin polymerization precatalysts. This was the first reported organic/inorganic hybrid sulfonic acid functionalized silica material capable of activating metallocenes for the polymerization of ethylene when small amounts of an alkylaluminum was added. Lastly, an organic/inorganic hybrid hyperbranched aminosilica material capable of capturing carbon dioxide from flue gas streams was synthesized. This material was determined to capture CO2 with capacities higher than currently reported aminosilica adsorbents.

The aim of this diploma thesis is to experimentally measure the Golem 1.1 fireplace insert for heating with and without a deflector in the Steko s.r.o. company’s test room. Following this measurement, the emissions of CO, CO2, oxygen content in the flue gases and the temperature in the flue duct are listed here and the efficiency is calculated for different modes of primary air sucked in the insert and for different numbers of fuel pieces.

This master‘s thesis describes thermal calculation and design of proportions of calorific components of a heat recovery steam generator (HRSG) for given input parameters of flue gas and output parameters of steam. Part of the thesis is design proportions of boiler drums, irrigation and transfer pipes. On the end of the thesis is counting draught losses and design drawning of steam generator.

Concentrations of CO, CO₂, and O₂ in woodstove flue gases are some of the measured inputs required by algorithms used to calculate woodstove efficiency by the stack loss method. Since these algorithms have been shown to be very sensitive to small errors in these input values, it was necessary to determine whether measurements of these compounds are subject to interference. Concentrations of CO, CO₂, and O₂ in a series of flue gas samples were measured using a variety of independent measurement techniques for each compound. The concentrations indicated by each of the measurement techniques for each compound and sample were compared to check for agreement. Disagreement among the measurement techniques for a given compound could indicate interference if some trend could be established. Tests were conducted on four samples taken randomly during each of three stove firings. / M.S.

AbstractThis research suggests that carbonation of concrete can significantly reduce greenhouse gas emissions, and to limit the 1.5º C rise within the next years. The accelerated carbonation method is of particular interest within the industry. By harnessing industrial flue gases, the carbonation process can be further accelerated. This study aims to assess whether the use of industrial flue gases to accelerate the carbonation of concrete can be economically viable compared to purchasing emission rights.The study is conducted theoretically with a focus on accelerated carbonation in waste management, only investigating industrial flue gases to speed up the carbonation process. Accelerated carbonation, where carbon dioxide is bound in concrete through a faster process than the natural carbonation process.The work demonstrates that the climate conditions of concrete affect carbon dioxide absorption, with outdoor concrete absorbing more carbon dioxide than indoor concrete. Additionally, the study shows that smaller fraction sizes in concrete result in greater carbon dioxide uptake, with the fraction size of 0-4 mm having the highest uptake of 58 kg CO2/ 𝑚3 in an hour. Cost calculations suggest that accelerated carbonation can be a cost-effective method for reducing carbon dioxide emissions compared to other techniques such as Carbon Capture and Storage (CCS) and Carbon Capture and Utilization (CCU). A difference in investment costs of 9 billion Swedish Crowns was observed, including repairs and maintenance. / Valet av byggmaterial är avgörande för både kostnader och miljöpåverkan inom byggbranschen. Genom att välja rätt material kan branschen minska sin miljöpåverkan och främja hållbar utveckling. Betong, är ett återvinningsbart material med lång historia som ett byggnadsmaterial och dess mineraliska sammansättning gör det till ett bra alternativ på rätt plats.Forskningen tyder att karbonatisering av betong kan minska utsläppen av växthusgaser betydligt, och accelererad karbonatisering har särskilt intresse inom branschen. Genom att utnyttja industriella rökgaser kan karbonatiseringsprocessen påskyndas ytterligare. Denna studie syftar till att bedöma om användningen av industriella rökgaser för att accelerera karbonatisering av betong kan vara ekonomiskt lönsamt jämfört med att köpa utsläppsrätter.Studien genomförs teoretiskt med fokus på accelererad karbonatisering vid avfallshantering, den undersöker endast industriella rökgaser för att påskynda karbonatiseringsprocessen.Accelererad karbonatisering, där koldioxid binds i betong genom en snabbare process än den naturliga karbonatiseringsprocessen.Arbetet visar att betongens klimatförhållanden såsom fukt och temperatur påverkar koldioxidabsorptionen, med betong som är utsatt för utomhusklimat som absorberar mer koldioxid än inomhusbetong. Dessutom visar studien, att större exponerad specifika ytor, såsom finare partikelstorlekar, leder till snabbare koldioxidupptag. Fraktionsstorleken 0–4 mm som har det högsta upptaget på 58 kg CO2/𝑚3.Kostnadsberäkningar tyder på att accelererad karbonatisering kan vara en kostnadseffektiv metod för att minska koldioxidutsläpp jämfört med andra tekniker som CCS och CCU. När det gäller implementering är investeringskostnadern väsentligt lägre än för implementering av en CCS-anläggning. Resultatet visar en skillnad i investeringskostnader på 9 miljarder kronor observerades, inklusive reparation och underhåll.