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The equilibrium equations relating dissolved CO2 , HC03- CO3-, H+, solid phase CaC03 , exchangeable H+ and ionic strength were programmed for simultaneous solution on a 7072 IBM digital computer. This routine was combined with an eXisting program which had been successfully used to relate the equilibrium of soluble and exchangeable Ca+ + ,Mg+ + ,Na+; dissolved Cl - , S04- ' and N03-; and solid phase CaS04 •2H20. The final systems analysis model thus developed accounted for most of the dissolved substances normally present in significant quantities in ground waters and soil solutions. This model made possible calculation of the equilibrium concentrations which would result if the concentration of one or more of these constituents were to be arbitrarily changed. This systems analysis model was used to predict the equilibrium concentrations of ionic species in soil solutions obtained from soils at moisture and carbon dioxide levels different from those prevailing in the original analysis. The soils used in this study were vastly different in chemical characteristics, texture, and genesis. Included were soils which were both acid and basic in reaction, calcareous and noncalcareous, gypsiferous and nongypsiferous, and both high and low in organic matter. In general, the chemical predictions obtained were of about the same level of accuracy as the experimental methods used to determine these chemical constituents. Soil cores from strata underlying an irrigated area were collected, and the 1: 1 soil-water extracts of these cores were analyzed for chemical constituents. The systems analysis model developed in this study was then used to estimate the concentrations of the chemical constituents which would have been in solution in the cores at the time they were sampled. The soil solutions calculated to be in most strata were similar to the underlying ground water, thus indicating a probable common origin for the water above and below the water table. It is believed that this systems analysis approach can, with minor modification, be used to predict changes in ground water quality as water percolates through strata of known chemical characteristics.

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Efficiency of particulate semiconductors for driving photocatalytic reactions is impractically low due to the recombination of excited carriers and intermediate species at the interface. In the literature it has been demonstrated internal depolarisation fields in ferroelectric materials separate electron and hole carriers, this gives rise to spatially distinct reduction and oxidation processes. It is hypothesised this property can supress the rate of back reactions and carrier recombination to improve photocatalytic efficiency. In this thesis the properties of ferroelectric particulates for driving photocatalytic reactions are investigated. Lithium niobate and barium titanate powders were suspended in aqueous solutions of acid black 1 or rhodamine b dye. Adsorption studies compared retention of dye in the double layer by the different powders. Under UV or simulated solar illumination barium titanate or lithium niobate powders photocatalytically decolourised the dye solutions. Powders of lithium niobate powder doped with magnesium or iron showed altered reaction rates and structural selectivity of decolourisation reactions. Photochemical deposition of silver nanoparticles at the surface of the barium titanate or lithium niobate powders increased the rate of photocatalytic decolourisation of rhodamine b solutions under UV or simulated solar illumination. Photochemical reduction of carbon dioxide to form formic acid and formaldehyde over lithium niobate powder was studied under UV illumination. Solid-liquid phase reactions were carried out using aqueous suspensions of powder bubbled with carbon dioxide gas. Solid-gas phase reactions were investigated using a purpose built reaction vessels loaded with carbon dioxide gas and water vapour. Under solid-gas phase conditions the rate of formation of products over lithium niobate powder was greater than over titanium dioxide powder.

In an effort to lower atmospheric carbon dioxide (C02) levels, a number of sequestration methods, including geological storage, ocean storage and mineral carbonation of CO2 have been proposed for British Columbia. The selection of a suitable sink depends largely on the geology available for a given region. A methodology for assessment of suitable raw material for the mineral carbonation process has been proposed. The Tulameen ultramafic complex is selected as a promising site for providing the raw feed for mineral C02 sequestration and representative dunites have been collected and examined. Carbonation tests of these dunites took place at the Albany Research Center in Oregon and C02 analyses in reaction products (up to 29.4 wt%) suggest 48-56% conversion to magnesite and silica for the dunites, and 18% conversion for a serpentinized dunite. Based on these results, one tonne of Tulameen dunite could potentially sequester up to 0.4 tomes of C02.

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