Yes / The FCC riser cracks gas oil into useful fuels such as gasoline, diesel and some lighter products such as ethylene and propylene, which are major building blocks for the polyethylene and polypropylene production. The production objective of the riser is usually the maximization of gasoline and diesel, but it can also be to maximize propylene. The optimization and parameter estimation of a six-lumped catalytic cracking reaction of gas oil in FCC is carried out to maximize the yield of propylene using an optimisation framework developed in gPROMS software 5.0 by optimizing mass flow rates and temperatures of catalyst and gas oil. The optimal values of 290.8 kg/s mass flow rate of catalyst and 53.4 kg/s mass flow rate of gas oil were obtained as propylene yield is maximized to give 8.95 wt%. When compared with the base case simulation value of 4.59 wt% propylene yield, the maximized propylene yield is increased by 95%.

The research presented in this thesis aims to assess the capacity of metal organic frameworks with open metal sites for the separation of olefin mixtures. Chapter 1 provides a background to the field, including industrial separation techniques, metal organic frameworks and their applications and the current state-of-the- art for olefin separation. Chapter 3 describes the experimental techniques used in this research. Ethylene and propylene adsorption and desorption isotherms on Ni-CPO-27 and HKUST-1 at a range of temperatures are presented and compared in Chapter 4, and used to calculate isosteric heats of adsorption at varying coverages using the virial method. These pure component isotherms are used in Chapter 5 to predict selectivities for the separation of binary mixtures using ideal adsorbed solution theory. Temperature programmed desorption is used in Chapter 5 to calculate the enthalpy of desorption using Redhead's method and the heating rate variation method, and the two results are compared. The results presented in Chapters 4 and 5 conclude that propylene/ethylene separation is possible using adsorption onto metal organic frameworks with open metal sites. A new in situ environmental gas cell for single crystal X-ray diffraction is developed in Chapter 6, and the challenges encountered during this development process are discussed. The dehydration of one framework, Co-CPO-27, is studied in detail using the environmental gas cell. A dehydrated structure of HKUST-1, obtained using the gas cell, is presented for the first time. Crystal structures for the complete dehydration-adsorption-delivery cycle for biologically active NO on Co-CPO-27 are presented in Chapter 7, showing the utility of the in situ gas cell for prolonged experiments in multiple different gaseous environments. The crystal structure of NO-loaded Co-CPO-27 improves upon the models suggested in the literature, and the treatment of the dual occupancy of the open metal sites by water and NO is discussed in depth. A crystal structure of CO-loaded Co-CPO-27 is obtained for the first time, and crystal structures of Co-CPO-27 in ethylene and propylene environments are presented.

Background: Despite the numerous pharmaceutical applications of alcohols andglycols, the interspecies differences with respect to their pharmacokinetics (PK) arepoorly understood. The aim of this research was to use in-vivo and in-vitro approaches to compare and model the PK characteristics across various species.Methods: Appropriate published in-vivo studies (in different species) foralcohols and glycols were carefully selected. PK analysis was performed using (a) noncompartmental analysis and (b) compartmental modeling to estimate relevant dose-independent PK parameters. Next, six alcohols (methanol, ethanol, 1 -propanol, 1 -butanol, 1-hexanol, and 1-octanol), two glycols (ethylene glycol and propylene glycol)and one secondary alcohol (2-propanol) were examined as in-vitro substrates for equine ADH using a UV spectrophotometric assay to evaluate the effect of molecular structure. Furthermore, in-vitro metabolism of ethanol and propylene glycol was also characterized in hepatic cytosolic fractions from rat, rabbit, dog and human and in-vitro in-vivo correlation for the hepatic disposition parameters was assessed. Finally, allometric scaling relationships for ethanol and propylene glycol PK parameters (in-vivo and in-vitro) were developed and validated.Results: Alcohols and glycols exhibited nonlinear PK due to saturable hepaticmetabolism in all species. The reported in-vivo data were well described by oneltwo compartment PK models with parallel saturable metabolism and first-order renalexcretion. In-vitro equine ADH experiments revealed differences in affinity andturnover between the substrates: Enzyme affinity (1/Km) and in-vitro intrinsic clearance (CLintin-vitro) correlated positively with logP values; glycols showed lower CLintin-vitro values than straight-chain alcohols. In-vitro hepatic cytosol studies yielded acceptable in-vivo predictions for the metabolic clearance (CLmet) of ethanol and propylene glycol in the rat, dog and human, but not the rabbit. Vdss, Vmax, CLintin-vitro, CLmet scaled allometrically across species with similar powers for both ethanol and propylene glycol, and good agreement between in-vivo and in-vitro scaling was noted. The allometric scaling models gave excellent predictions when externally validated against in-vivo concentration-time data. Conclusions: The present research demonstrates .the successful application of amodeling-based approach to elucidate interspecies relationships for alcohols andglycols, compounds which exhibit nonlinear PK and mainly low hepatic extractionbehavior. The in-vitro experimental systems have been used successfully forcharacterizing alcohol/glycol metabolism and predicting in-vivo disposition.

Early-lactating dairy cows mobilize body protein, primarily from skeletal muscle, to provide amino acids which are directed towards gluconeogenesis and milk protein synthesis. Propylene glycol (PG) is a precursor of ruminal propionate, and our hypothesis was that its dietary inclusion could attenuate skeletal muscle wasting by reducing amino acid-driven gluconeogenesis. The major objectives of this study were to delineate the effects of pre- and post-partum PG supplementation in transition dairy cows on whole-body nitrogen (N) balance, urinary 3-methylhistidine (3-MH) excretion, body composition, and gene expression profiles for the major protein degradation pathways in skeletal muscle. Sixteen pregnant cows (7 primiparous and 9 multiparous) were paired based on expected calving dates and then randomly assigned within each pair to either a basal diet (control) or basal diet plus 600 mL/d of PG (PG). Diets were fed twice daily for ad libitum intake, and PG was fed in equal amounts as a top dress. All measurements were conducted at 3 time intervals starting at d -14 ± 5, d 15 and d 38 relative to calving. Propylene glycol had no effect (P > 0.05) on whole-body N balance, urinary 3-MH excretion, and body composition. However, N balance was lower (P < 0.001) at d 15 and d 38, compared to d -14. Urinary excretion of 3-MH was lower at d -14 than at d 15 (P = 0.01) and d 38 (P = 0.001). Supplemental PG had no effect (P > 0.05) on body weight (BW), and all components of empty BW. On average, cows fed both diets mobilized 19 kg of body fat and 14 kg of body protein between d -14 and d 38. Supplemental PG had no effect on mRNA abundance in skeletal muscle for m-calpain (P = 0.96) and 14-kDa ubiquitin-carrier protein E2 (14-kDa E2) (P = 0.54); however, PG supplementation down-regulated mRNA expression for µ-calpain at d 15 (P = 0.02), and tended to down-regulate mRNA expression for ubiquitin at d 15 (P = 0.07) and proteasome 26S subunit-ATPase at d 38 (P = 0.097). Relative to calving, mRNA abundance for m-calpain (P = 0.02) and µ-calpain (P = 0.005) were higher at d 15 compared to d -14 and d 38. Messenger RNA abundance for ubiquitin (P = 0.07) and 14-kDa E2 (P = 0.005) were lower at d 38 compared to d 15. In summary, these results demonstrate that up-regulation of the Ca2+-dependent and ubiquitin-mediated proteolytic pathways are the mechanisms by which skeletal muscle wasting occurs in early-lactating cows. In addition, dietary supplementation with PG may down-regulate some of these proteolytic pathways, thereby potentially attenuating undesirable skeletal muscle wasting.

Early-lactating dairy cows mobilize body protein, primarily from skeletal muscle, to provide amino acids which are directed towards gluconeogenesis and milk protein synthesis. Propylene glycol (PG) is a precursor of ruminal propionate, and our hypothesis was that its dietary inclusion could attenuate skeletal muscle wasting by reducing amino acid-driven gluconeogenesis. The major objectives of this study were to delineate the effects of pre- and post-partum PG supplementation in transition dairy cows on whole-body nitrogen (N) balance, urinary 3-methylhistidine (3-MH) excretion, body composition, and gene expression profiles for the major protein degradation pathways in skeletal muscle. Sixteen pregnant cows (7 primiparous and 9 multiparous) were paired based on expected calving dates and then randomly assigned within each pair to either a basal diet (control) or basal diet plus 600 mL/d of PG (PG). Diets were fed twice daily for ad libitum intake, and PG was fed in equal amounts as a top dress. All measurements were conducted at 3 time intervals starting at d -14 ± 5, d 15 and d 38 relative to calving. Propylene glycol had no effect (P > 0.05) on whole-body N balance, urinary 3-MH excretion, and body composition. However, N balance was lower (P < 0.001) at d 15 and d 38, compared to d -14. Urinary excretion of 3-MH was lower at d -14 than at d 15 (P = 0.01) and d 38 (P = 0.001). Supplemental PG had no effect (P > 0.05) on body weight (BW), and all components of empty BW. On average, cows fed both diets mobilized 19 kg of body fat and 14 kg of body protein between d -14 and d 38. Supplemental PG had no effect on mRNA abundance in skeletal muscle for m-calpain (P = 0.96) and 14-kDa ubiquitin-carrier protein E2 (14-kDa E2) (P = 0.54); however, PG supplementation down-regulated mRNA expression for µ-calpain at d 15 (P = 0.02), and tended to down-regulate mRNA expression for ubiquitin at d 15 (P = 0.07) and proteasome 26S subunit-ATPase at d 38 (P = 0.097). Relative to calving, mRNA abundance for m-calpain (P = 0.02) and µ-calpain (P = 0.005) were higher at d 15 compared to d -14 and d 38. Messenger RNA abundance for ubiquitin (P = 0.07) and 14-kDa E2 (P = 0.005) were lower at d 38 compared to d 15. In summary, these results demonstrate that up-regulation of the Ca2+-dependent and ubiquitin-mediated proteolytic pathways are the mechanisms by which skeletal muscle wasting occurs in early-lactating cows. In addition, dietary supplementation with PG may down-regulate some of these proteolytic pathways, thereby potentially attenuating undesirable skeletal muscle wasting.

Direct, gas phase propylene epoxidation reactions are carried out on model slabs representing Ru-Cu(111) bimetallic and Cu(111) metallic catalyst surfaces with periodic Density Functional Theory (DFT) calculations. Ru-Cu(111) surface is modelled as a Cu(111) monolayer totally covering the surface of Ru(0001) surface underneath. The catalytic activity is evaluated following the generally accepted oxametallacycle mechanism. It is shown that the Ru-Cu(111) surface has a lower energy barrier (0.48 eV) for the stripping of the allylic hydrogen of propylene and a higher energy barrier (0.92 eV) towards propylene oxametallacycle (OMMP) formation compared to 0.75 eV barrier for OMMP formation and 0.83 eV barrier for allylic hydrogen stripping on Cu(111), and thus ineffective for propylene oxide production based on the investigated models and mechanism. In order to analyze the observed inability of the Ru-Cu(111) surface to selectively catalyze propylene oxide formation, a Lewis acid probe, SO2, was adsorbed on the oxygenated Cu(111) and Ru-Cu(111) surfaces and the binding energies, a measure of the basicity of the chemisorbed oxygen on the surfaces, on two systems are compared. As a conclusion, the reason behind this ineffectiveness of the Ru-Cu(111) surface for selectively catalyzing propylene epoxidation is related to the higher basicity of the atomic oxygen adsorbed on Ru-Cu(111) compared to the oxygen on Cu(111). The results are consistent both with recent publications about propylene epoxidation and previous studies performed about the structure of Ru-Cu catalysts.

No description available.

Thesis (Ph. D.)--University of Nebraska, 1925. / Bibliography: p. 27-28.

Orientador: Watson Loh / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-07T11:45:40Z (GMT). No. of bitstreams: 1 Anselmo_AleteiaGarcia_M.pdf: 1348079 bytes, checksum: 03480ee468bf0185ae57c464c2020046 (MD5) Previous issue date: 2006 / Resumo: Neste trabalho estudou-se a partição do poli (óxido de propileno), PPO, poli (N - isopropilacrilamida), PNIPAM, poli (N-vinil-2- pirrolidona), PVP, e poli (óxido de etileno), PEO em sistemas líquidos bifásicos, entre as fases aquosa e orgânica (CHCI3, CH2Cl2 e C6H5CI). Os resultados obtidos indicaram que a partição do PPO, polímero hidrofóbico, é preferencial para as fases orgânicas em todos os sistemas bifásicos estudados, enquanto que para os polímeros hidrofílicos, tais como, o PVP e PNIPAM, a partição ocorre preferencialmente para a fase aquosa. As entalpias de transferência, da fase aquosa para a fase orgânica para estes polímeros, foram determinadas através da técnica de titulação calorimétrica isotérmica e revelaram que para todos os sistemas estudados o processo de transferência é endotérmico. Isto sugere que a solvatação dos polímeros pela fase aquosa é mais energética que quando comparada com a solvatação dos polímeros pela fase orgânica, e que, portanto, para o PPO, o processo de transferência é entropicamente dirigido. Spitzer e colaboradores observaram resultados similares para a partição do poli (óxido de etileno), PEO, em sistemas bifásicos contendo CHCl3 e CH2Cl2, (Spitzer et aI.; J. Phys. Chem. B 2002, 106, 12448). Em comparação com o PEO, os valores de entalpia de transferência obtidos para o PPO são mais positivos, o mesmo pode ser observado para o coeficiente de partição. A partição do PPO pode ser explicada em termos de efeito hidrofóbico, o qual propõe a liberação das moléculas de água que estariam solvatando o polímero quando este é transferido para a fase orgânica. / Abstract: In this work the partitioning of poly (propylene oxide), PPO, poly (Nisopropylacrylamide), PNIPAM, poly (vinyl pyrrolidone), PVP and poly (ethylene oxide), PEO between aqueous and organic phases (CHCI3, CH2Cl2 and C6H5CI) was investigated. The results reveal that for all biphasic systems the partitioning of PPO, a hydrophobic polymer, to organic phase is predominant, while for PVP and PNIPAM, hydrophilic polymers, partitioning is always preferential towards the aqueous phase. The enthalpies of transfer for these polymers from aqueous to organic phases were calorimetrically determined and revealed an endothermic process for all the systems investigated, suggesting that solvatation of polymers in aqueous phase is more energetic than organic phase and, therefore, the process of transfer must be entropically driven for PPO. Spitzer and coworkers observed similar results for the partitioning of PEO in biphasic systems containing CHCl3 and CH2Cl2, (Spitzer et aI.; J. Phys. Chem. B 2002, 106, 12448). In comparison with PEO, the enthalpies of transfer of PPO are more positive, the same being observed for the partition coefficients. These data indicate that partitioning of PPO can be explained within the framework of the hydrophobic effect, whereby water molecules that were originally solvating the polymer are released when this is transferred to the organic phase. / Mestrado / Físico-Química / Mestre em Química

Metal-organic frameworks (MOFs) are porous crystalline materials built by metal clusters coordinated to organic ligands. Synthesis of MOFs has attracted considerable attention in recent decades, owing to its potential for a wide range of applications such as gas separation, dye adsorption, and catalysis, etc. The development of MOF membranes further enhances the potential of this type of material in industrial applications. Membrane fabrication methods, including in-situ growth, seeded secondary growth, interfacial growth, and vapor-phase deposition, have been widely studied. However, most of these methods either require a complicated synthesis procedure or are timeconsuming. Recently, the electrochemical synthesis has emerged as a highly promising approach to fabricate MOF membranes in a scalable manner, because it allows shorter synthesis time, milder synthesis condition, continuous reaction, and crystal self-healing. In this thesis, for the first time, an aqueously cathodic deposition (ACD) approach was developed to fabricate ZIF-8 type of MOF membranes without the addition of any supporting electrolyte or modulator. The fabrication process used 100% water as the sole solvent, and a low-defect density membrane was obtained in only 60 min under room temperature without any pre-synthesis treatment. The membrane exhibited superior performance in C3H6/C3H8 separation with C3H6 permeance of 182 GPU and selectivity of 142, making it sit at the upper bound of permeance versus selectivity graph, outperforming the majority of the published data up to 2019. Notably, this approach used an extremely low current density (0.13 mA cm-2) operated under a facile apparatus setup, enabling an attractive method for environmentally friendly, energy-efficient, and scalable MOF membrane fabrications. This work demonstrates the enormous potential of aqueously electrochemical deposition of the MOF membrane in future research.