During military operations, a small fraction of propellant mass is not consumed during firing and is deposited onto the ground surface. Soluble propellant constituents can be released from particulate residues into the environment. The release of uncombusted propellant residues and transformation products results in soil, surface water, and ultimately groundwater contamination. It is important to study the potential for off-site migration of munitions and to provide qualitative data that helps better understand transit of these propellant constituents. Propellant constituents of interest for this study were nitroglycerine (NG), 2,4-dinitrotoluine (2,4-DNT), 2,6-dinitrotoluine (2,6-DNT), and nitroguanidine (NQ). The goal of this work is to determine fate and transport parameters, partition/distribution coefficients and transformation rates for these compounds in three soils that represent a range of geographic locations and soil properties. This supports a companion study that looks at dissolution of constituents from fired and unfired solid propellant formulations and their transport in soil.

There is little doubt that moisture is a very important factor in relation to material durability. The need for tools to assist in the better understanding and systematic evaluation of moisture movement with the view of incorporating the results within the overall framework of the defect investigation, quality control, and long-term monitoring of moisture, have led to the development of various moisture monitoring and predicting techniques. With the purpose of helping to harmonise the interests in this field, this thesis addresses three major issues in the area of wood moisture. Various studies carried out have been shown that there are substantial discrepancies between specific timber species and published charts for equilibrium moisture content. One of the main objectives of this research was to focus on establishing the equilibrium moisture content for a range of relative humidity and temperature on an individual basis, for twenty commercially important species used in the United Kingdom. The rationale for carrying out the project, the results from the initial trial and the mainstream experiment, the hardware and methodology developed are provided. To meet the requirements of long term accurate and reliable moisture monitoring and to provide comprehensive moisture information, a new type of moisture sensor and related measurement system were developed. The methodology of system design and test procedures are described, emphasising the anti-polarisation method, noise rejection and contact resistance reduction techniques employed. Other aspects of the electrical performance of timber were also investigated. Results from a case study showed that the sensor developed can operate in the critical range of relative humidity with sensitive and accuracy. In the final part of the project, two moisture transport models were developed. Mathematical prediction models in both one dimension and three dimensions are presented for simulating the adsorption and desorption processes in wood. Comparisons are made against long-term experimental data for the one dimensional model. The finite differential method was employed to solve the mathematical expressions developed, resulting in accurate prediction of concentration-driven moisture flows. Investigations were also carried out into the moisture diffusion coefficient and moisture behaviour in the three principal wood directions by using the sensor developed which provided isothermal real-time continuous data.

La sorption du cadmium sur la calcite est étudiée en système ternaire, en présence, simultanément d’un ligand organique (malonate) et du cadmium. D’abord nous avons étudié l’interaction entre le malonate et la calcite. L’influence du malonate sur la solubilité de la calcite, le signal du malonate en spectroscopie infrarouge et enfin la modélisation des isothermes d’adsorption par un modèle de complexation de surface à trois plans (CD-MUSIC) nous ont permis de proposer un modèle pour la spéciation du malonate à la surface de la calcite et d’estimer quantitativement l’adsorption. Ensuite, nous avons étudié la sorption du cadmium sur la calcite, respectivement en absence et en présence de malonate. En absence de malonate, l’adsorption du cadmium donne lieu à une isotherme classique, de valeurs connues. La modélisation néanmoins révèle quelques difficultés de paramètrage. L’étude de la sorption en réacteur à écoulement continu sous conditions proches de l’équilibre CaCO3-H2O-CO2 met en évidence une parfaite réversibilité adsorption/désorption du cadmium. Notons que aucune expérience de sorption ne dépassait une durée totale de 60 heures. En présence de malonate, expériences et modélisations indiquent un effet négatif du malonate sur la sorption du cadmium. La cinétique de sorption est notablement ralentie et le cadmium est, en partie, fixé plus fortement à la surface. Les résultats tendent à montrer que la présence de malonate ralentit considérablement l’atteinte d’un équilibre de sorption du cadmium sur la calcite. / The sorption of cadmium by calcite was studied in a ternary system, with an organic ligand (malonate) and cadmium simultaneously present in solution. First we studied the interaction between malonate and calcite. The influence of malonate on the solubility of calcite, malonate spectra in infrared spectroscopy, and the modelling of isotherms by a 3-plane surface complexation model (CD-MUSIC) allowed us to propose a model for the speciation of malonate at the surface of calcite and to estimate adsorption quantitatively. In a second step, we have studied the sorption of cadmium by calcite, without and with malonate respectively. When malonate was not present, cadmium sorption by calcite gave rise to an isotherm with known values. Modelling however revealed some difficulties with parametrisation. Studying sorption under continuous flow in a “Stirred Flow Through Reactor” under conditions close to CaCO3-H2O-CO2 equilibrium, showed perfectly reversible adsorption/desorption of cadmium. Note that sorption experiments were conducted over 15 to 60 hours at maximum. When malonate was present, experiments and modelling indicated that malonate reduced the sorption of cadmium. Sorption kinetics were significantly lower and cadmium, in part, sorbed more strongly on the calcite surface. The results tend to show that the presence of malonate slows down the reach of sorption equilibrium of cadmium with calcite.

<p>In general, the research focuses on sequestration of naphthenic acids (NAs) from simulated oil sands process water (OSPW) conditions using engineered copolymers known as &beta;-cyclodextrin-based polyurethanes. The thesis research is divided into two main parts; <i>i)</i> synthesis and characterization of &beta;-cyclodextrin-based polyurethanes, and <i>ii)</i> sorption studies of the copolymer materials with NAs from aqueous solutions.</p> <o>In the first part, &beta;-cyclodextrin (&beta;-CD) was crosslinked with five types of linker molecules, respectively, under various synthetic conditions. The various diisocyanates investigated as linkers include the following: 1,6-hexamethylene diisocyanate (HDI), 4,4'-dicyclohexylmethane diisocyanate (CDI), 4,4'-diphenylmethane diisocyanate (MDI), 1,4-phenylene diisocyanate (PDI) and 1,5-naphthalene diisocyanate (NDI). The polyurethanes (PUs) were systematically designed at different mole ratios of monomers by maintaining &beta;-CD and varying the relative mole ratio of diisocyanate monomer from unity to greater values. Diffuse Reflectance Infrared Fourier Transform spectroscopy (DRIFTS), solid state ¹³C CP-MAS NMR, solution state ¹H/¹³C NMR spectroscopy, thermogravimetric analysis (TGA), elemental analysis (CHN), nitrogen porosimetry, and a dye-based (p-nitrophenol; PNP, and phenolphthalein; phth) sorption method were used to characterize the copolymer materials. In general, the &beta;-CD PUs were insoluble in water except for &beta;-CD crosslinked with HDI at the 1:1 mole ratio which was moderately water soluble. All techniques show complementary results about the structural and compositional characterization, particularly for the estimation of the ratios between the co-monomers. The optimal preparation of copolymer materials for sorption-based applications occurs for &beta;-CD/linker monomer mole ratios from 1:1 to 1:3. There is a maximum limit of the crosslinking density which is ~ 1:7 (&beta;-CD:linker) according to the steric effects of the substituents in the annular region of &beta;-CD. Also, the copolymers were generally found to be mesoporous with relatively low surface area (BET; ~10¹ m²/g) and they appear to exhibit swelling in aqueous solution due to hydration as observed from the estimation of the dye-based surface areas using PNP. The surface accessibilities of the &beta;-CD inclusion sites ranged between 1-100%, as evidenced by the decolourization of phenolphthalein (phth) due to the formation of 1:1 &beta;-CD/phth inclusion complexes.</p> <p>In the second part, the inclusion of NAs and its surrogates with three well known types of cyclodextrin (&alpha;-, &beta;-, and &gamma;-CD) was confirmed using negative ion mode electrospray ionization (ESI). The CDs were found to form well-defined 1:1 inclusion complexes. The binding constant (K2) of NAs and its surrogates inclusion with &beta;-CD was determined indirectly using the spectral displacement technique and were found to be 10³-10⁴ M^-1 (surrogates) and ~ 10⁴ M^-1 (NAs), respectively. Furthermore, the binding constants were found to increase with an increase of the lipophilic surface area (LSA) of the surrogates. The sorption results of NAs with three different types of &beta;-CD materials (i.e. &beta;-CD PU, &beta;-CD crosslinked with epichlorohydrin (EP) and a silica-based mesoporous material containing &beta;-CD), showed &beta;-CD PU had a greater affinity. The sorption capacity (~ 0 - 75.5 mg NAs/g copolymer) and binding affinity (~10³ - 10⁴ M^-1) of &beta;-CD PUs varied due to the nature of linker monomer and the mole ratio of the co-monomers. Aromatic-based copolymers showed high sorption binding affinity while aliphatic-based copolymers showed a relatively high sorption capacity at the co-monomer ratio. Finally, Syncrude-Derived NAs showed fluorescent characteristics which contradict the classic definition of NAs. Further studies using UV-Vis and fluorescence emission spectroscopy showed potential development of an analytical method that can be used to quantify NAs in OSPW for <i>in-situ</i> field applications.

Activated Carbon (AC) is an amorphous carbon-based material characterized with a large surface area (~ 1,000 m2/g) and consists primarily of graphitic (sp2 hybrid) layers. Its amphoteric chemical property results because of the chemical treatment of the surface of AC with oxidizing agents, reducing agents, and grafting agents. β-cyclodextrin (β-CD) is a very interesting carbohydrate oligomer that provides very strong binding ability for small organic guest molecules in its inner cavity (6.0 ~ 6.5 Å) by van der Waals interactions and hydrogen bond formation between the guest molecules and the host. <p>Surface modification of AC with β-CD was synthesized by chemical methods: oxidation with HNO3, reduction with LiAlH4, and grafting β-CD onto the surface of AC via organic linkers such as glutaraldehyde and 1,4-phenylene diisocyanate. This surface grafted AC with β-CD, then, was evaluated for its surface area and sorption performance by using a solution dye sorption method using dye adsorbates. <p>Surface functional groups produced from oxidation (carboxylic acid, lactone, quinine, phenol, and nitro groups), reduction (alcohol and amine groups), and grafting (imine, hemiacetal, and urethane bonds) methods including microscopy of untreated, surface modified, and grafted ACs were characterized by various surface characterization methods: Diffuse Reflectance Infra-red Fourier Transform Spectroscopy (DRIFTS), Scanning Electron Microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Thermogravimetric analysis (TGA), Differential thermogravimetry (DTG), Matrix Assisted Laser Desorption Ionization Time of Flight mass spectrometry (MALDI TOF MS), and Electron spin resonance (ESR) spectroscopy. A chemical method, the Boehm method, was used for identifying surface bound acidic and basic functional groups. Nitrogen porosimetry was used to analyze the surface area and pore structure characteristics of AC, surface modified ACs, and grafted ACs. <p>p-nitrophenol (PNP) and methylene blue (MB) were used as adsorbates for the dye sorption method. PNP and MB were used to measure the sorption performance of grafted ACs at equilibrium using UV-vis spectrophotometry in aqueous solution. Sorption capacity (Qe), surface area (m2/g), and binding affinity characteristics [KF (L/g), KL (g/mol), and KBET (L/g)] were determined at equilibrium conditions using fundamental sorption models such as Langmuir, Freundlich, and BET isotherms. The sorption performance of grafted ACs and granular AC were different according to the difference in surface area and pore structure characteristics of each material.

The adsorption characteristics of an oil sands tailings water (OSTW) mixture of naphthenic acids were determined using a batch partitioning method for two soils from the Alberta oil sands region. The soils were mineral peat mixtures produced during salvage operations, with Soil 1 having a higher organic carbon fraction (foc) than Soil 2. Naphthenic acids are a significant toxic byproduct of bitumen extraction, and are acutely toxic to aquatic organisms. The sorption of naphthenic acids as affected by a high ionic strength solution was examined using a synthetic groundwater (SGW) mixture.<p>The adsorption isotherms were found to be linear in all cases. All tests were conducted at 4oC, and at a pH of 8.0 ± 0.4, reflective of the conditions in a tailings settling facility near Fort McMurray, AB. The adsorption characteristics of the naphthenic acids in the SGW solution were compared to that of the mixture in Milli-Q water for the two soils. In the presence of SGW, the adsorption coefficient (Kd) for the mixture of naphthenic acids on Soil 1 was an order of magnitude higher than that observed with the same soil and the Milli-Q water mixture, increasing from 1.9 ± 0.2 mL/g to 17.8 ± 1.5 mL/g. The adsorption coefficient for the mixture of naphthenic acids on Soil 2 was also observably higher in the SGW mixture, increasing from 1.3 ± 0.15 mL/g to 3.7 ± 0.2 mL/g. In order to determine whether preferential sorption is exhibited by a particular species within the mixture, the relative fractional abundance of the individual naphthenic acids was plotted as a 3-dimensional histogram for carbon numbers 5 to 37. It was found that for all Z families (where Z is a measure of the number of carbon ring structures), naphthenic acids within the middle range of carbon numbers showed preferential sorption. A two sample t-test confirmed that the naphthenic acids in the carbon number groupings 15 to 24 and 25 to 37 sorbed significantly in the SGW mixture when compared to those in the carbon number grouping of 5 to 14. It was concluded that select constituents of oil sands naphthenic acids mixtures sorb strongly to soil under conditions of elevated salinity and therefore adsorption could be an important attenuating mechanism in groundwater transport. Furthermore, preferential sorption of the individual naphthenic acids is important with respect to toxicity since lower molecular weight naphthenic acids are believed to have a more pronounced toxic effect. Overall, the measured adsorption coefficients indicate that there can be significant sorption of OSTW derived naphthenic acids to soils.

<p>In general, the research focuses on sequestration of naphthenic acids (NAs) from simulated oil sands process water (OSPW) conditions using engineered copolymers known as &beta;-cyclodextrin-based polyurethanes. The thesis research is divided into two main parts; <i>i)</i> synthesis and characterization of &beta;-cyclodextrin-based polyurethanes, and <i>ii)</i> sorption studies of the copolymer materials with NAs from aqueous solutions.</p> <o>In the first part, &beta;-cyclodextrin (&beta;-CD) was crosslinked with five types of linker molecules, respectively, under various synthetic conditions. The various diisocyanates investigated as linkers include the following: 1,6-hexamethylene diisocyanate (HDI), 4,4'-dicyclohexylmethane diisocyanate (CDI), 4,4'-diphenylmethane diisocyanate (MDI), 1,4-phenylene diisocyanate (PDI) and 1,5-naphthalene diisocyanate (NDI). The polyurethanes (PUs) were systematically designed at different mole ratios of monomers by maintaining &beta;-CD and varying the relative mole ratio of diisocyanate monomer from unity to greater values. Diffuse Reflectance Infrared Fourier Transform spectroscopy (DRIFTS), solid state ¹³C CP-MAS NMR, solution state ¹H/¹³C NMR spectroscopy, thermogravimetric analysis (TGA), elemental analysis (CHN), nitrogen porosimetry, and a dye-based (p-nitrophenol; PNP, and phenolphthalein; phth) sorption method were used to characterize the copolymer materials. In general, the &beta;-CD PUs were insoluble in water except for &beta;-CD crosslinked with HDI at the 1:1 mole ratio which was moderately water soluble. All techniques show complementary results about the structural and compositional characterization, particularly for the estimation of the ratios between the co-monomers. The optimal preparation of copolymer materials for sorption-based applications occurs for &beta;-CD/linker monomer mole ratios from 1:1 to 1:3. There is a maximum limit of the crosslinking density which is ~ 1:7 (&beta;-CD:linker) according to the steric effects of the substituents in the annular region of &beta;-CD. Also, the copolymers were generally found to be mesoporous with relatively low surface area (BET; ~10¹ m²/g) and they appear to exhibit swelling in aqueous solution due to hydration as observed from the estimation of the dye-based surface areas using PNP. The surface accessibilities of the &beta;-CD inclusion sites ranged between 1-100%, as evidenced by the decolourization of phenolphthalein (phth) due to the formation of 1:1 &beta;-CD/phth inclusion complexes.</p> <p>In the second part, the inclusion of NAs and its surrogates with three well known types of cyclodextrin (&alpha;-, &beta;-, and &gamma;-CD) was confirmed using negative ion mode electrospray ionization (ESI). The CDs were found to form well-defined 1:1 inclusion complexes. The binding constant (K2) of NAs and its surrogates inclusion with &beta;-CD was determined indirectly using the spectral displacement technique and were found to be 10³-10⁴ M^-1 (surrogates) and ~ 10⁴ M^-1 (NAs), respectively. Furthermore, the binding constants were found to increase with an increase of the lipophilic surface area (LSA) of the surrogates. The sorption results of NAs with three different types of &beta;-CD materials (i.e. &beta;-CD PU, &beta;-CD crosslinked with epichlorohydrin (EP) and a silica-based mesoporous material containing &beta;-CD), showed &beta;-CD PU had a greater affinity. The sorption capacity (~ 0 - 75.5 mg NAs/g copolymer) and binding affinity (~10³ - 10⁴ M^-1) of &beta;-CD PUs varied due to the nature of linker monomer and the mole ratio of the co-monomers. Aromatic-based copolymers showed high sorption binding affinity while aliphatic-based copolymers showed a relatively high sorption capacity at the co-monomer ratio. Finally, Syncrude-Derived NAs showed fluorescent characteristics which contradict the classic definition of NAs. Further studies using UV-Vis and fluorescence emission spectroscopy showed potential development of an analytical method that can be used to quantify NAs in OSPW for <i>in-situ</i> field applications.

Activated Carbon (AC) is an amorphous carbon-based material characterized with a large surface area (~ 1,000 m2/g) and consists primarily of graphitic (sp2 hybrid) layers. Its amphoteric chemical property results because of the chemical treatment of the surface of AC with oxidizing agents, reducing agents, and grafting agents. β-cyclodextrin (β-CD) is a very interesting carbohydrate oligomer that provides very strong binding ability for small organic guest molecules in its inner cavity (6.0 ~ 6.5 Å) by van der Waals interactions and hydrogen bond formation between the guest molecules and the host. <p>Surface modification of AC with β-CD was synthesized by chemical methods: oxidation with HNO3, reduction with LiAlH4, and grafting β-CD onto the surface of AC via organic linkers such as glutaraldehyde and 1,4-phenylene diisocyanate. This surface grafted AC with β-CD, then, was evaluated for its surface area and sorption performance by using a solution dye sorption method using dye adsorbates. <p>Surface functional groups produced from oxidation (carboxylic acid, lactone, quinine, phenol, and nitro groups), reduction (alcohol and amine groups), and grafting (imine, hemiacetal, and urethane bonds) methods including microscopy of untreated, surface modified, and grafted ACs were characterized by various surface characterization methods: Diffuse Reflectance Infra-red Fourier Transform Spectroscopy (DRIFTS), Scanning Electron Microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Thermogravimetric analysis (TGA), Differential thermogravimetry (DTG), Matrix Assisted Laser Desorption Ionization Time of Flight mass spectrometry (MALDI TOF MS), and Electron spin resonance (ESR) spectroscopy. A chemical method, the Boehm method, was used for identifying surface bound acidic and basic functional groups. Nitrogen porosimetry was used to analyze the surface area and pore structure characteristics of AC, surface modified ACs, and grafted ACs. <p>p-nitrophenol (PNP) and methylene blue (MB) were used as adsorbates for the dye sorption method. PNP and MB were used to measure the sorption performance of grafted ACs at equilibrium using UV-vis spectrophotometry in aqueous solution. Sorption capacity (Qe), surface area (m2/g), and binding affinity characteristics [KF (L/g), KL (g/mol), and KBET (L/g)] were determined at equilibrium conditions using fundamental sorption models such as Langmuir, Freundlich, and BET isotherms. The sorption performance of grafted ACs and granular AC were different according to the difference in surface area and pore structure characteristics of each material.

The adsorption characteristics of an oil sands tailings water (OSTW) mixture of naphthenic acids were determined using a batch partitioning method for two soils from the Alberta oil sands region. The soils were mineral peat mixtures produced during salvage operations, with Soil 1 having a higher organic carbon fraction (foc) than Soil 2. Naphthenic acids are a significant toxic byproduct of bitumen extraction, and are acutely toxic to aquatic organisms. The sorption of naphthenic acids as affected by a high ionic strength solution was examined using a synthetic groundwater (SGW) mixture.<p>The adsorption isotherms were found to be linear in all cases. All tests were conducted at 4oC, and at a pH of 8.0 ± 0.4, reflective of the conditions in a tailings settling facility near Fort McMurray, AB. The adsorption characteristics of the naphthenic acids in the SGW solution were compared to that of the mixture in Milli-Q water for the two soils. In the presence of SGW, the adsorption coefficient (Kd) for the mixture of naphthenic acids on Soil 1 was an order of magnitude higher than that observed with the same soil and the Milli-Q water mixture, increasing from 1.9 ± 0.2 mL/g to 17.8 ± 1.5 mL/g. The adsorption coefficient for the mixture of naphthenic acids on Soil 2 was also observably higher in the SGW mixture, increasing from 1.3 ± 0.15 mL/g to 3.7 ± 0.2 mL/g. In order to determine whether preferential sorption is exhibited by a particular species within the mixture, the relative fractional abundance of the individual naphthenic acids was plotted as a 3-dimensional histogram for carbon numbers 5 to 37. It was found that for all Z families (where Z is a measure of the number of carbon ring structures), naphthenic acids within the middle range of carbon numbers showed preferential sorption. A two sample t-test confirmed that the naphthenic acids in the carbon number groupings 15 to 24 and 25 to 37 sorbed significantly in the SGW mixture when compared to those in the carbon number grouping of 5 to 14. It was concluded that select constituents of oil sands naphthenic acids mixtures sorb strongly to soil under conditions of elevated salinity and therefore adsorption could be an important attenuating mechanism in groundwater transport. Furthermore, preferential sorption of the individual naphthenic acids is important with respect to toxicity since lower molecular weight naphthenic acids are believed to have a more pronounced toxic effect. Overall, the measured adsorption coefficients indicate that there can be significant sorption of OSTW derived naphthenic acids to soils.

The overall goal of this study is to evaluate the ability of novel nanostructured adsorbent media (NTAs, iron sulfides (FeS2 and FeS)) to remove arsenic, selenium and mercury from ash and scrubber pond effluents. The NTAs aim to enhance arsenic removal from solution compared to conventional adsorbents. The iron sulfides are expected to produce stable residuals for ultimate disposal after removing As, Se and Hg from solution, so that removal of these compounds from wastewaters will not result in contamination of soils and groundwaters. Methods for reliably and economically producing these materials were developed. The synthesized NTAs and iron sulfides were characterized by surface analysis techniques such as XRD, FT-IR, SEM-EDS, TEM, XPS, AFM and N2-adsorption. These analyses indicated that Ti(25)-SBA-15 has highly ordered hexagonal mesopores, MT has interparticle mesopores, pyrite (FeS2) forms crystalline, nonporous rectangular nanoparticles (<500 nm), and mackinawite (FeS) forms amorphous, nonporous nanoparticles (<100 nm). Kinetic and equilibrium tests for As(III, V) removal were conducted with NTAs over a range of pH (4, 7, 9.5). The rates of arsenic uptake were very fast and followed a bi-phasic sorption pattern, where sorption was fast for the first 10 minutes, and then slowed and was almost completed within 200 minutes. Distinct sorption maxima for As(III) removal were observed between pH 7 and pH 9.5 for MT and between pH 4 and pH 7 for Ti(25)-SBA-15. The amount of As(V) adsorbed generally decreased as pH increased. In addition, a surface complexation model (SCM) based on the diffuse layer model (DLM) was used to predict arsenic adsorption envelopes by NTAs under various environmental conditions. The SCM for As(III, V) adsorption by NTAs demonstrated the role of mono- and bidentate surface complexes in arsenic adsorption. A batch reactor system was employed in an anaerobic chamber to conduct experiments to characterize both the removal of As, Se, Hg from solution and their subsequent reactions with iron sulfides. Experiment variables for removal experiments included: contaminant valence state (As(V), As(III), Se(VI), Se(IV), Hg(II)); adsorbent/reactant type (FeS, FeS2); adsorbent/reactant concentration; pH (7, 8, 9, 10); and competing ion (SO42-) concentration (0, 1, 10 mM). Experimental variables for reaction experiments were reaction time (up to 30 days) at pH 8 and oxidation states of contaminants. In addition, the stability of iron sulfides (FeS2, FeS) combined with target compounds was investigated by measuring the ability of the target compounds to resist release to the aqueous phase after removal. These experiments showed that iron sulfides were good adsorbent/reactants for target contaminants in spite of the presence of sulfate. This was particularly true at intermediate concentrations of target compounds. The experiments also demonstrated that iron sulfides interacted with target contaminants in such a way to improve their resistance to being released back to solution as pH was changed. Therefore, this study demonstrates the ability of novel nanostructured adsorbent media to remove arsenic, selenium and mercury from ash and scrubber pond effluents and the ability of iron sulfides to produce residuals that are stable when disposed in landfills.