Chemical Engineering electronic theses and dissertations (MU)
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The items in this collection are the theses and dissertations written by students of the Department of Chemical Engineering. Some items may be viewed only by members of the University of Missouri System and/or University of Missouri-Columbia. Click on one of the browse buttons above for a complete listing of the works.
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Item Simulation model for drug distribution(University of Missouri--Columbia, 1980) Yeh, Yu-San; Luecke, Richard H."OBJECTIVES: Association equilibrium calculations for drug-protein binding will lead to the knowledge of the free (unbound) concentration of the drug in the plasma. The free drug in the plasma is generally considered to be available for distribution of the drug to the tissue which is involved in the excretion of the drug (15). The objectives of this study were: 1. To develop appropriate equations to compute drug distribution for two drugs on binding sites on serum albumin with special emphasis on free drug concentrations. 2. To develop a computer program to carry out the computations, print tabular output and also to prepare Cal Comp plots for competetive displacement in teractions on serum albumin. 3. To develop appropriate equations to compute the effects of two drugs competing for an enzymatic site in the liver and the consequences of such inhibition on the excretion of a drug in the bile. 4. To develop a computer program to carry out the computations for competetive inhibition on the drug concentrations in the bile, print tabular output and prepare Cal Comp plots. 5. To compare the mathematical model and computer program with experimental data for two binary anticoagulant drugs system, Warfarin-Bromosulfophthalein (BSP) and Warfarin-Bilirubin."--Page 3.Item A hydrodynamic study of coal extrudates in fiber-water suspensions(University of Missouri--Columbia, 1987) Gerdes, Perry V.; Marrero, T. R.This research is focused on the development and utilization of a system capable of obtaining hydrodynamic data for coal extrudates flowing in tandem through water and water-fiber suspensions. Coal-logs can carry more coal than slurry pipelines and fibers can reduce the frictional losses. A horizontal closed loop system was constructed of galvanized tubing (2.25 in. nominal diameter). Instrumentation included a sonic flowmeter, a laser and photocell, pressure sensors, and electro-mikes. Data were retrieved and analyzed with a microcomputer. A jet pump supplied by a centrifugal pump propelled the coal-logs, water and fiber. Pressure drop along a straight section of pipe, and degree of lift-off were measured. At flow rates between 2 and 9 fps the effects of coal-log to pipe diameter ratio (D /D = .628, .691, .839) were investigated in water and 0.25, 1.0 and 1.5 weight percent wood pulp suspensions. The water-pulp mixtures are suspending media and should support moving capsules such that abrasion andhead losses will be reduced. As anticipated, the pulp suspensions themselves (no capsules) reduced the drag losses relative to water by over 10% at certain flow rates for fiber concentrations at and above 1.0%. All the capsule (coal-log) water head losses were found to be between 10 and 40 percent greater than those of water at their optimum velocities (velocities corresponding to the smallest head losses). The addition of fibers to water increased the head losses of capsules. This increase in head loss is caused by the tendency of fibers to accumulate above the coal-logs and hold them down against the pipe floor. This unexpected effect can be due to either a flaw in the pumping system diffuser or the narrow gap between the coal-log and pipe. This effect would probably not occur in larger pipe systems.Item Hazardous metal wastes : landfill alternatives(University of Missouri--Columbia, 1983) Cook, Lloyd Gregory; Marrero, Thomas R.This study was proposed to find technologically available processes which could be used as economically feasible alternatives to land disposal of hazardous wastes. The scope of the study was limited to heavy metal contaminated hazardous wastes generated in Missouri. Data on 95 such waste streams were taken from the Missouri Department of Natural Resources’ Hazardous Waste Generator Registration Files. Economic criteria reduced the number of streams under consideration to twelve. Two streams, an electric arc furnace flue dust and an electroplating wastewater treatment sludge, were chosen for detailed study. An electrothermic reduction roast process called the Plasmazinc process was proposed to recover iron, lead and zinc from the electric arc furnace flue dust. In this process, an electrically generated plasma is used to supply heat to a low shaft furnace which contains the dust and an excess of coke. A reducing atmosphere of carbon monoxide and hydrogen is maintained throughout the process so that lead and zinc can be collected as metals in a splash condenser. Iron is tapped from the bottom of the furnace. This process was developed by SKF Steel of Sweden. A profitability analysis for a Plasmazinc plant capable of processing 91,000 kkg of dust annually suggested that the dust would have to be delivered to the plant free of charge for it to be feasible. The discounted cash flow rate of return for this case was found to be 15.1%. A reverse osmosis unit integrated into the rinsing system was proposed to recycle nickel plating salts currently contaminating the electroplating wastewater sludge. As suggested by the generator, the 99.97. reduction of nickel in the sludge which would result could be sufficient to induce the EPA to grant a regulatory exclusion for the waste. The estimated savings in disposal and plating chemicals' costs would effect a projected discounted cash flow rate of return of 15.8%. Elimination of these two streams would reduce the amount of hazardous waste generated in Missouri and disposed of on or in the land by 10%.Item Moderate temperature hydrolysis of corn starch for alcohol fermentation(University of Missouri--Columbia, 1981) Alam, Shahriar Nur; Dunlap, Charles E.Whether production of ethanol from grain by fermentation has a positive energy balance is still a big controversey. A recent study showed that the energy output/input ratio varies between 1.08 to 1.16. About 18% of the total plant energy input is in the hydrolysis unit, which is a relatively high temperature process carried out at between 90° to 130°C. Hydrolysis at a moderate temperature of 65°C could increase the heat output/input ratio significantly. Aiming at this, the activities of ten commercially available enzymes were assayed to select the enzyme with the highest activity per unit cost. Hydrolysis of corn mash was carried out at a temperature of 65°C, varying the concentration of enzymes and the time sequence of addition of the enzymes. A mathematical model was developed based on the experimental results which could predict the dextrose equivalent as a function of different process parameters. Using this equation, the optimum level of enzyme concentrations and the time sequence of their addition were determined. The scope of further investigation is also discussed.Item Cathode active materials synthesis using glycerol-based solvent for Li-ion and Na-ion batteries : preparation, characterization, and techno-economic analysis(University of Missouri--Columbia, 2025) Xu, Siqi; Xing, Yangchuan[EMBARGOED UNTIL 12/01/2026] This dissertation investigates cathode active materials (CAMs) synthesis using glycerol solvent for Li-ion and Na-ion batteries. Glycerol, which can be produced from biomass and is also a byproduct from the biodiesel esterification process, provides a green manufacturing route to produce CAMs. The use of glycerol to replace water makes the CAM production process environmentally friendly and cost effective. The research work in this dissertation establishes quantitative links between precursor formulation, particle formation mechanisms, long-term cycling behavior in coin cell batteries, and the techno-economic feasibility of the manufacturing process. The first part of research was focused on developing a physics-based model describing the evaporation and solidification of multicomponent precursor droplets containing glycerol, water, and ethanol. This work was aimed at understanding drying of sprayed glycerol droplets containing chemical precursors and other components. The model captures the transition from constant-rate drying to diffusion-limited crust formation and reproduces experimental single-droplet drying behavior. Under typical experimental drying conditions (50 μm initial diameter, 623 K air stream), the total drying time takes approximately 6–7 s. When ethanol is involved, increasing the ethanol concentration accelerates evaporation and reduces the crust-formation diameter from ~33 μm to ~31 μm, while glycerol-rich formulations prolong process due to higher glycerol viscosity and mass transfer resistance. These findings provide a mechanistic basis for interpreting hollowing and surface-instability features observed in spray-dried powders. The second part of research was focused on an experimental investigation of how water, ethanol, and ethylene glycol modify the behavior of glycerol-based precursor droplets and influence the morphology, structure, and electrochemical properties of spray-dried LiNi0.8Co0.15Al0.05O2 (NCA) using glycerol-based precursor solutions. It was found that ethanol increased the first-cycle discharge capacity from 140.6 mAh g⁻¹ (at 10%) to 181.4 mAh g⁻¹ (at 20%) and improved capacity retention to 90.1% in 120 cycles at 0.1 C rate. Further, it was found adding ethylene glycol (EG) to the precursor solution resulted in the best structural ordering at 10–15% EG, yielding an 89.2% retention. In contrast, a 20% water in the precursor reduced the first-cycle capacity to 127.9 mAh g⁻¹ and produced the lowest retention (78.2%). These results show that precursor compositions strongly influence the glycerol droplet drying behaviors, cation distribution, and electrochemical performance. The third part of research was focused on the synthesis of sodium transition metal oxide CAMs in a glycerol-assisted thermal decomposition route. In particular, the P2-type Na₀.₆₇Ni₀.₃₃Mn₀.₆₇O₂ and its Zr-doped derivative were studied. It was found that the Zr substitution slightly expands interlayer spacing and suppresses P2–O2 transitions, therefore stabilizing the P2 phase for better performance. The undoped material showed an initial capacity of 131.9 mAh g⁻¹ at 0.1 C but quickly faded to 64.9 mAh g⁻¹ after 200 cycles (0.3 C). The Zr-doped sample showed a lower initial capacity of 119.2 mAh g⁻¹ at 0.1 C, but maintained a capacity at 105.4 mAh g⁻¹ after 200 cycles (0.3 C), demonstrating a much enhanced structural stability. Finally, a two-step techno-economic analysis (TEA) was used to investigate the economic viability of Na-ion CAM powder production in the spray drying-based glycerol process. It was found that the minimum cathode-material selling price (MCSP) is most sensitive to precursor costs, plant scale, and discount rate. The chemical precursors, sodium acetate, nickel acetate, and manganese acetate, dominate material contributions, while optimized precursor concentration and increased throughput can markedly reduce MCSP. The TEA results indicate that the production process can achieve substantial cost reductions in both material and processing expenses compared to the conventional carbonate co-precipitation method. Sensitivity analysis reveals that the production process can lower the MCSP to $12.57/kg vs. $14.40/kg from the co-precipitation process. Additionally, every 20% reduction in material cost would result in a $1.39/kg decrease in the MCSP. Accordingly, manufacturing of Na0.67Ni0.33Mn0.67O2 from the spray drying process is particularly well-suited to meet the U.S. Department of Energy's battery cost target of $80/kWh, highlighting the promise of this process as a viable approach for Na-ion CAMs.