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Experimental studies are reported, on the single and binary component adsorption of various gases and organic vapours on activated carbons (Anthrasorb CC818H and CC818M) at different temperatures. Experiments were performed for methane, ethane, methane-ethane mixtures, acetone and carbon tetra-chloride vapours. Single component isotherms were established for all the adsorbates over a range of temperatures (-6 to 50°C). The empirical Langmuir and Freundlich models correlate the results well. The Polanyi adsorption potential theory depicts all of the single component data. Other empirical and theoretical isotherm equations were also tested. Binary isotherms were obtained for methane-ethane mixtures on both Anthrasorb CC818H and CC818M. An empirical method was employed to model the binary adsorption data using single component empirical Langmuir parameters to express the binary isotherm of each component in a given mixture. The Polanyi adsorption potential theory correlates the binary adsorption data fairly well. Breakthrough data for single and binary adsorbates (over a range of concentrations and flowrates) were obtained and mathematical models established which represents the results. A finite difference technique was used to model the fixed bed breakthrough data. Two simplified asymptotic models (linear driving force and pore diffusion control) were also used to correlate the single component data. For the binary adsorption of methane-ethane mixtures, a linear driving force model was successfully employed to correlate the experimental breakthrough curves. Isothermal fixed bed experiments to desorb acetone from Anthrasorb CC818H over the range of temperatures (150-250°C) showed that Anthrasorb can be used to completely remove such an organic vapour and be regenerated for further use.

A preconcentration procedure has been developed which at one and the same time raises the concentration of the two groups of elements, AS, Au, Cu, Os, Pb, Pd, Pt and Rh and As, Sb, Se, So, To and T1, in many natural materials above the detection limits of the spark-source mass spectrometric technique and separates them from interfering matrix elements. The technique involves the cementation of the elements from solution on amalgamated aluminium powder which can be pelleted directly to form the electrode for spark source mass spectrometric analysis. Through the use of wet oxidative digestions and oxygen flaskcombustion oxidation procedures in conjunction with the cementation procedure the above elements have been determined in a number of biological, geological and environmental samples.

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This thesis is concerned with the theoretical and esqjerimental aspects of low temperature infra red spectroscopic studies of ionic solvation. Isotopically dilute methanolic and aqueous solutions were investigated in the fundamental infra red region, particularly in the 0-H stretching region of the spectrum. Systematic room temperature investigations were undertaken for aqueous and methanolic electrolyte solutions as a fimction of the salt concentrations. These results provided certain trends regarding solvent- solute interactions which the low temperature experiments on the same solutions confirmed so that cation and anion solvation models could be put forward. ParticiiLar attention was given to the study of methanolic and aqueous polyatomic ion solutions to provide further evidence as to whether these anions cause the formation of free or weakly bonded 0-H groups. Infra red studies of the tetrahydroborate anion in various pure solvents and binary mixtures suggested an interaction between BH.;and water protons which had spectroscopic characteristics of hydrogenbonding. Finally vibrational studies of methanolic tetraalkylammonium halide solutions in inert and bulk solvent solutions produced a range of anion solvates where both primary and secondary solvation could be observed.

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