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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.

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With the rapid growth of the world population and the process of industrialization of modern society, the demand for energy continues to rise sharply. There is a pessimistic prediction that a peak of consumption primarily fossil fuels will happen in the 2020s to 2030s, hence it is urgent to develop alternative renewable clean energy sources before this coming energy crisis. But the availability of renewable clean energy always is discontinuous, uncontrollable, and unstable. Besides, the generated renewable energy cannot be used directly. Therefore, an energy storage system is urgently needed as the medium to harvest and store the energy generated from the intermittent renewable resource, and also to regulate the electricity output, and improve the tolerance ability of the power grid to renewable energy. Rechargeable aqueous zinc-ion battery, especially those that use mild electrolytes, is drawing more and more attention in the past decades and is regarded as the most promising candidate for large-scale energy storage systems. Compared with the widely used lithium-ion battery which dominated the commercial energy market now, the aqueous zinc-ion battery holds the merits of high theoretical capacity (820 mAh/g gravimetric capacity and 5855 mAh/m3 volumetric capacity), low electrochemical potential (-0.763 V vs. SHE) and high energy density due to the two-electron redox reaction, high abundance in the earth crust and high mass production, low toxicity, and environmental benignity, and the most valuable advantage intrinsic safety in aqueous electrolyte. In this dissertation, the first part focuses on the preliminary application of an aqueous zinc-ion battery. One kind of planar on-chip aqueous zinc-ion micro-battery with high-rate performance was designed and fabricated. The PEDOT and MnO2 cathode can suppress the dissolution of electrode material which can highly improve the cycling performance of the micro-battery. The as-prepared micro-battery displays a high specific capacity of 25.8 μAh/cm2 after 25 activation cycles at a current density of 1 mA/cm2. A reversible specific capacity of 6.2 μAh/cm2 is achieved after 200 cycles, with 55.4 % of the initial discharge capacity retention. To improve the cycling performance of the aqueous zinc-ion battery, the second part of this thesis is preparing a highly enhanced reversibility Zn anode by in-situ texturing. The crystal plane (002)-textured Zn anode with an ultrathin passivation layer suppressed the Zn corrosion and enhanced the full battery performance. Based on these merits, the cycling stability of the Zn anode is enhanced from 791 hours to more than 1500 hours. The coulombic efficiency (CE) of a Zn||Ti asymmetric cell is greater than 90% over 500-hour cycles. For the Zn||MnO2 full cell, the addition of H3PO4 into the electrolyte improves both the rate capability and cycling stability of Zn||MnO2 cells. More importantly, a highly reversible Zn||O2 full cell is demonstrated at a large depth of discharge of Zn (DODZn > 10%), projecting the lower bounds of the cell-level specific energy of lithium-ion batteries.:Abstract I Kurzfassung III List of Abbreviations IX Chapter 1 Background and motivation 1 1.1 Research motivation 1 1.2 Aim of this dissertation 2 1.3 Dissertation structure 3 Chapter 2 Introduction of aqueous zinc-ion battery and anode protection strategies 5 2.1 Introduction of aqueous zinc-ion battery 5 2.2 The challenges of zinc anode 8 2.2.1 Dendrites and protrusion 9 2.2.2 Hydrogen evolution reaction 10 2.2.3 Passivation layer 10 2.3 The strategies of zinc anode protection 11 2.3.1 Surface engineering 11 2.3.2 Electrolyte modification 15 2.3.3 3D structural skeleton and alloy strategies 22 Chapter 3 Experiment characterizations and calculations 25 3.1 Electrochemical methods 25 3.1.1 Chronoamperometry 25 3.1.2 Chronopotentiometry 26 3.1.3 Cyclic voltammetry 27 3.1.4 Galvanostatic charge/discharge 28 3.1.5 Electrochemical impedance spectroscopy 29 3.1.6 Tafel measurement 30 3.2 Characterization methods 31 3.2.1 X-ray diffraction 31 3.2.2 Scanning electron microscope 32 3.2.3 X-ray photoelectron spectroscopy 32 3.2.4 Raman spectroscopy 33 3.3 Experimental calculations 34 3.3.1 b value calculation 34 3.3.2 CE calculation 34 3.3.3 RTC calculation 35 3.3.4 DFT calculation 36 3.3.5 DOD calculation 37 3.3.6 Corrosion rate calculation 38 Chapter 4 A planar on-chip aqueous zinc-ion micro-battery with high-rate performance 41 4.1 Introduction 41 4.2 Experimental section 43 4.2.1 Interdigitated electrodes 43 4.2.2 Preparation of micro-battery 44 4.2.3 Microstructural properties characterization 45 4.2.4 Electrochemical characterization 45 4.3 Results and discussion 46 4.3.1 Characterization of micro-battery 46 4.3.2 Electrochemical performance measurement 49 4.4 Conclusions 56 Chapter 5 Highly enhanced reversibility of a Zn anode by in-situ texturing 57 5.1 Introduction 57 5.2 Experimental section 63 5.2.1 Preparation of the textured Zn anode 63 5.2.2 Synthesis of cathode materials 63 5.2.3 Electrochemical and material characterizations 64 5.3 Results and discussions 64 5.3.1 Nonuniform Zn deposition on an epitaxial substrate 65 5.3.2 In-situ texturing and SEI formation during the cycling 72 5.3.3 Full-cell performance 77 5.4 Conclusions 81 Chapter 6 Summary and outlook 83 6.1 Summary 83 6.2 Outlook 84 References： 87 Acknowledgment 99 Publications 101 Curriculum Vitae 103 Selbstständigkeitserklärung 105

Values of the rate constant for the alkaline hydrolysis of methyl acetate in various aqueous-organic solvent mixtures (dimethyl sulfoxide 0<x40.2, dioxane 0 <, x., < 0.2, methyl ethyl ketone 0<x<0.06 and diglyme, i. e. ether-bis (2-methyloxethyl) 0x<0.10) have been determined for the temperatures 15 0 C, 25 0C and 35 0C conductometrically. To interpret these results the approach adapted is to experimentally determine the activity coefficient of the ester (YE ) and the activity of the water (aH20', mechanistically, at least one molecule of water is involved in the rate-determining step) and then to use the Bronsted-Bjerrum equation to determine the residual activity coefficient ratio of the participating ions, y (Yf - for Oil the transition state). Values of YE and aH 20 have been determined by a transpiration method, using gas-chromatographic analysis of the vapours of solutions of methyl acetate in aqueous-organic solvent mixtures of dir. ethyl sulfoxide, dioxane, methyl ethyl ketone and diglyme in the same composition ranges as above, tetrahydrofuran 04x org z<, 0.15, methanol, ethanol and tert-butanol in t1h6e range 04x0.20'at 25oC. These results indicate that on changing org the solvent composition YE varies by a larger factor than is predicted for the ratio YOH-/yýO_ by the Debye-Iluckel approach, and hence is the dominant factor in determining the effects of solvent composition on the rates of the hydrolysis. This is in contradiction to the assumptions of the electrostatic theories of Laidler and Eyring, and of Amis and Jaffe. The gas-chromatographic results also indicate that whilst the concentration of the water varies in each mixture studied, the activity coefficient varies in the opposite way to produce almost constant values of aý, 0* Using the transpiratioii/gas-chromatogralýlic method, the thermodynamic properties of the ternary systems, methyl acetate-water-organic Solvcat, using the organic solvents mentioned above (excepting, diglyme) have been investigated, and the results indicate that the variation of *ýE with solvent composition, for the dilute solutions of ester used, can be estimated from the thermodynamic properties of the binary water-organic solvent mixtures, using the Gibbs-Dahem equation. Single ion activity coefficients in the literature for small negative ions, to represent the OH_ ion, and for large ions, to rep-resent the transition state ion, have been used to explain the experimentally fomd variation of the residual activity coefficient -ratio with solvent composition. Hence, it is concluded that the importance of the parameters involved in the hydrolysis of esters - an ion-molecule reaction - in aqueousorganic solvent mixtures are in the order of Ymolecule > aH 20> YOH_/YM+ -> (dielectric constant), and that the nonelectrostatic effects -- thermodynamic effects - are more important in these studies than the electrostatic effects. From a preliminary investigation of the data in the literature the thermodynamic approach also yields a valid interpretation of the effect of solvent composition on the rates of the acid hydrolysis of esters. / Ministry of Science and Higher Education of Iran

This research project was conducted to evaluate the effects of adhesive type, wood species, and cure temperature on the strength and durability properties of a finger joint. The adhesives were a resorcinolormaldehyde(RF),polyurethane/aqueous emulsion polymer (PU/AEP), and a resorcinolormaldehyde/soy-isolate honeymoon system. The species of wood were keruing (Dipterocarpus spp.), southern pine (Pinus spp.), and Douglasir (Pseudotsuga menziesii). The cure temperatures of the adhesives were ambient (26-35° C, 78-95° F) and elevated (43-49° C, 110-120° F). Joints were subjected to three test procedures; a tension test, a bending test, and a bending test following an accelerated aging procedure. The response variables measured for each of the bending tests included modulus of rupture, modulus of elasticity, and percent wood failure. The response variables measured for the tension tests were tensile strength and percent wood failure. The RF adhesive performed the best in flexural and tensile strength of the three adhesives studied. However in most cases, the PU/AEP adhesive could be considered a comparable system. Given adequate adhesive performance, strength and stiffness of the joints studied were dependent on density of the wood species, with keruing having the greatest density.

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