With the background of health issues regarding the consumption of tobacco, the widespread availability of safer nicotine products and a harm reduction policy is encouraged. A cigarette alternative is designed to deliver a dose of medicinal nicotine within a timeframe comparable to that of a cigarette, and gives much of what smokers expect from a cigarette without the risks of smoking tobacco. The general purpose of this Ph.D. project is to study the process of flashing atomization and dispersion, with a view to supporting the development of a cigarette replacement device. In order to test the effectiveness of the nicotine formulations, the analysis is carried out sizing the droplets of the aerosols at the position where human oropharynx locates, to support the further research on the deposition of droplets in the human respiratory tract. A mechanical lung has been assembled and programmed to trigger the ‘cigarette-like’ devices with different inhalation profiles, and a dual laser system has been designed to measure the global actuation flow characteristics (e.g. spray velocity and opacity). In order to efficiently acquire sufficient droplet information (e.g. diameter and aspect ratio) from images of in and out of focus droplets, a multi-threshold algorithm is developed and successfully implemented in the automatic particle/droplet image analysis (PDIA) system. It increases the depth of field (DoF) of small particles with diameters smaller than 50μm, and it performs more efficiently than the dual threshold methods which are widely used in the commercial software. A numerical multi-component two-phase actuation flow model has been developed, in order to test different formulations within various flow domains of the cigarette replacement devices. The simulated results of the numerical model have been validated with the experimental measurements and the results of previous researchers. In order to acquire an aerosol with relatively low and steady mass flow rate of nicotine, it is recommended that the mass fraction of propellant (HFA 134a) should be kept around 75%~90% to avoid the sharp temperature drop causing the sensation of freezing. The actuator nozzle diameter should be 0.2mm~0.3mm to produce a flow with relatively low mass flow rate. Furthermore the numerical model is capable of predicting the residual mass median diameter (MMD) of the spray, by using evaporation model of multicomponent liquid droplets, to quantify the sprays. Two different formulations with 95% and 98% mass fraction of HFA 134a, and two prototype cigarette alternatives with different expansion chamber volumes, have been analyzed by the numerical model and compared with the dual laser measurements. In addition, it considers the spray character by high speed imaging, with the special interest in the flashing phenomena and droplet sizes. It concludes that a larger expansion chamber volume enhances the propellant evaporation, recirculation, bubble generation and growth inside the chamber, and it made a significant improvement to produce finer sprays. Although the formulation with 98% of HFA 134a can generate smaller droplets, the formulation with 95% of HFA 134a produces more steady puffs with relatively low mass flow rate.

This study used magnetite (Fe3O4) nanoparticles (NPs), mesoporous silica coated magnetite NPs (SCMNPs) and thiol functionalised silica-coated magnetite nanoparticles (SH-SCMNPs) for Hg(II) removal and recovery from water. The Fe3O4 NPs were prepared via conventional co-precipitation methods. Mesoporous silica coating was created on dense liquid-silica coated magnetite NPs (DLSC-Fe3O4 NPs) using cetyltri-methyl-ammonium chloride (CTAC) as molecular templates and followed by a sol-gel reaction. SCMNPs were functionalised with 3-MPTMS using the co-condensation method. Functionalisation of SCMNPs with this specific organic group was performed to enhance the selectivity of the magnetic NPs towards Hg(II). The characteristics of these particles were assessed at different stages in the production process. The hydrodynamic particle size distribution increased from an average diameter of ~75 nm for Fe3O4 NPs to ~105 nm after silica coating, and was found to be ~111 nm after functionalisation with thiol. The particles were found to be almost spherical with a uniform mesoporous structure with a pore size of ~2.1 nm. The particles were strongly responsive to an external magnetic field making separation from solution possible in less than 1 minute using a permanent magnet. Batch tests were used to evaluate the feasibility of the prepared NPs for the adsorption and desorption of Hg (II) from synthetic wastewater. SH-SCMNPs displayed a high removal efficiency for Hg(II) uptake, with 90% of Hg(II) removed during the first 5 minutes and equilibrium in less than 15 minutes. The adsorption efficiency was highly pH dependant. Adsorption was not affected by the majority of coexisting cations and anions under the conditions tested. 3 M HCl and thiourea in a 3 M HCl solution was an effective eluent for the desorption of adsorbed-Hg on SCMNPs and SH-SCMNPs respectively. This did not result in the destruction of the nanoparticles and they could subsequently be reused, without loss of their activity, in further adsorption tests. The adsorption characteristics of the particles were quantified in a series of isotherm experiments using Hg(II) solution concentrations of between 40 and 1000 μg L−1 at adsorbent concentrations of 4 and 8 mg L-1. The adsorption capacity was higher than for other commonly used adsorbents. Both the Langmuir and Freundlich isotherm models were applied to the isotherm data and the maximum adsorption capacity was achieved when the ratio of adsorbent to adsorbate was low. A semi-continuous method for using the process at a lab scale was developed and was found to be successful in the removal and recovery of Hg(II) and confirmed the results of the batch experiments.

Marine biofouling is the accumulation of organisms on underwater surfaces, causing increased ship hydrodynamic drag, which results in higher fuel consumption and decreased speed and range. Biofilms constitute a major component of the overall biofouling and may lead to a 14 % increase in ship fuel costs. Past solutions to antifouling (AF) have used toxic coatings which have subsequently been shown to severely affect marine life. The prohibited use of these antifoulants has led to the search for bio-inspired AF strategies. Current approaches towards the production of alternative coatings include the incorporation of natural AF compounds into paints. Screening assays for novel AF compounds are often separated into two categories; toxicity and AF assays. Increasingly there is evidence that active compounds affect organisms at non-toxic concentrations, hence, the necessity for more insightful AF testing, such as bacterial and diatom attachment. This study assessed natural product (NP) antifouling performance of two marine seaweeds (Chondrus crispus and Bifurcaria bifurcata) and two isolated pure compounds from terrestrial sources (usnic acid and juglone) against two marine biofilm bacteria, Cobetia marina and Marinobacter hydrocarbonoclasticus. Overall it was found that all NPs affected bacterial attachment, however, juglone demonstrated the best AF performance against both bacterial species at a concentration range between 5 - 20 ppm. Biofilm colonisation is a surface related phenomenon, thus novel bioassays have been developed to directly test biofilm attachment and growth on NP-containing coatings for both static and hydrodynamic conditions. This study has incorporated NPs into a model coating system, using two formulations in order to assess their effect on biofilm growth. Laboratory screening of NP-containing coatings is often largely unexplored mainly due to difficulties in assessing their activity over short experimental time scales (typically only a maximum of a few days). To date there are only a limited number of reports on laboratory assessment for antifouling paints and their effect on biofilm growth and/or attachment. In this study, NP-containing model paints were applied on to coupons, placed in 24-well plates and then inoculated with the marine biofilm forming bacteria. This has been achieved by the development of a novel bioassay protocol that has allowed the in situ observation of biofilm formation and growth, by corroborating different techniques such as a multidetection microplate reader and confocal laser scanning microscopy (through nucleic acid staining). There was good correlation between the two techniques which showed that the NP containing coatings significantly inhibited biofilm growth and also revealed marked differences in biofilm structure (e.g. bio-volume, morphology and thickness). The goal of this study was to develop a new protocol to allow assessment of biofilm formation on coatings in a high throughput non-invasive manner. New protocols and methods using microfluidic devices were developed for the assessment of bacterial attachments and initial biofilm formation in the presence and absence of a NP under hydrodynamic conditions. This led to the development and fabrication of a novel lab-on-a-chip device for the investigation of the biofilm response to different hydrodynamic conditions. The microfluidic flow channels were designed using computational fluid dynamic simulations so as to have a pre-defined, homogeneous wall shear stress in the channels, ranging from 0.03 to 4.30 Pa, which are relevant to in-service conditions on a ship hull.

This research aims to understand the transition of established entrepreneurial firms into sustainable entrepreneurship ventures in Malaysia using a competency based perspective. The research considers established entrepreneurial firms attempts to acquire green technology financing. By observing a green technology financing scheme (GTFS) a competency trap is identified that constrains established entrepreneurial firms, regardless of their excellent financing track record and previous business success in other ventures. Utilising Rasmussen et al.’s (2011, 2014) evolutionary entrepreneurial competency framework, the research examines how established entrepreneurial firms develop the entrepreneurial competencies to overcome this trap and acquire green technology financing. By comparing different established entrepreneurial firms during the process to acquire financing, the research examined the GTFS contextual influence on the deployment of competencies, revealing the multi-faceted nature of the competency trap. In order to acquire GTFS financing the research identified two sets of entrepreneurial necessary competencies; (i) opportunity refinement competencies (ii) resource acquisition competencies. However, development of these competencies is influenced by the established entrepreneurial firms’ paths and the competency trap. Four different pathways to address the competency trap are highlighted. This emphasizes the need for more contextual based research at multiple levels of analysis to understand established entrepreneurial firms’ transition into sustainable entrepreneurship ventures.

Carbon Capture and Storage (CCS) is one option to meet the increasing energy demand as well as reduce net CO2 emissions to the atmosphere. Chemical Looping Combustion (CLC) is a promising CCS technology proposed to meet the challenge of mitigating the carbon dioxide (CO2) emissions. CLC process can be based on interconnected fluidized beds, consisting of air reactor, fuel reactor and oxygen carrier (OC) which undergoes redox reactions while it circulates between the reactors. The main products are CO2 and water, thus eliminating the need of an additional energy intensive CO2 separation. The feasibility of CLC depends on the oxygen carrier's (OC) ability to transfer O2 from air reactor to fuel reactor and have sufficient oxygen capacity, high reactivity and withstand a high number of redox cycles without significant loss in performance. OCs based on transition metal oxides of Cu, Co, Fe, Mn and Ni has been explored. Nevertheless, research is focused on improving the OCs performance with the aim to overcome their various practical limitations. Mechanical mixing and impregnation which fails to provide a high degree of dispersion and high metal loading respectively are commonly used for OC synthesis. Very few works have been reported for Mn-oxide and co-precipitated oxygen carriers. The few studies on co-precipitated OCs mainly use strong base as precipitants. One drawback to this is the repetitive washing of precipitate to remove excess alkali ions and controlled loading of active components cannot be easily obtained. In this study, weak base instead of strong base was used in the synthesis of OCs. This is the first time this controlled approach has been applied to prepare oxygen carrier in CLC for manganese and iron. This thesis is a novel research on development and detailed investigation of co-precipitated Mn-oxide and Fe-oxide OCs with ZrO2 and combined ZrO2–CeO2 support. The reaction kinetics, stability and oxygen transfer capacity (OTC) of the OCs were studied by TGA up to 1173 K in H2, CO and CH4. Characterization of physical and chemical structures of particles was obtained by SEM-EDX, XRD, BET and pycnometer. The result reveals that regardless of the composition of the co-precipitated oxygen carriers, there was no interaction of the metal oxides with the support material which could have altered the thermodynamics of the redox system. Furthermore, co-precipitated Mn/Zr and Fe/Zr OCs were more reactive than their counterpart prepared by impregnation and mechanical mixing. Also, changes in reactivity and OTC suggest that the synergistic effect varies with ratios of the single oxides in the bimetallic OCs. Co-precipitated Mn-rich oxygen carriers were more reactive than Fe-rich OCs. Interestingly, OCs with zirconia-ceria support exhibited activation tendency behaviour. Moreover, the use of combined zirconia-ceria for bimetallic Mn-Fe oxide reversed the characteristic progressive decrease in the performance of the OC with equimolar composition. For co-precipitated Mn-Fe Oxide oxygen carriers, zirconia content of 44 wt. % is sufficient to maintain the mechanical integrity of the particles during redox reactions compared to a zirconia content of 20 wt. %. This research has resulted in the development of highly reactive and stable oxygen carriers, which are promising for CLC. Mn/Zr OC reached full conversion in less than 48 secs and bimetallic Mn-Fe OCs reached 30% conversion in less than 43 secs in CH4 and maintained stability in a thirty multicycle test. The redox reaction kinetics of the most reactive oxygen carrier using CH4, H2, CO and air was investigated at isothermal conditions (973-1173 K) to determine the kinetic parameters. Models of the reduction and oxidation reactions were selected by using a model fitting method. The nucleation model was the most statistically significant and suitable model for describing the reduction and oxidation behaviour of the oxygen carrier. The values of activation energy obtained for the reduction reaction in CH4, H2 and CO were 142.8 KJ/mol, 32.95 KJ/mol and 26.37 KJ/mol respectively. Whereas, for the oxidation reaction, the activation energy obtained using air was 28.83 KJ/mol. In the application of co-precipitation technique for the synthesis of multicomponent materials, a heterogeneous product could be obtained from using improper preparation conditions. Results from this research have demonstrated that, the application of the well-designed co-precipitation procedure effectively produced composite materials (up to four co-precipitated mixed metal oxides) with controlled compositions and homogeneous dispersion. Furthermore, this study provides insight into the fundamental behaviours of co-precipitated manganese and iron based oxygen carriers to aid the design and optimization of future materials development.

Carbon Capture and Storage (CCS) has been considered as one of the most promising techniques to reduce anthropogenic CO2 emissions in the atmosphere. As an alternative to replace the traditional technology of aqueous amine scrubbing, solid adsorbents looping technology (SALT) has attracted growing attention. Among various solid adsorbent materials, carbon-based materials with unique properties such as wide availability, relatively low cost, highly porous structure ease of regeneration, and stable cyclic performance, have been considered as promising candidates at both low pressure and moderate to high partial pressure. In this PhD research, activated carbon spheres derived from two different precursors, which are phenolic resin and coal-tar pitch, have been prepared and modified with potassium intercalation to improve CO2 capture performance for post combustion carbon capture. The project aims to investigate the factors that affect CO2 adsorption performance for post combustion carbon capture. Firstly, series of spherical activated carbon beads (with a uniform diameter of ca. 0.6-0.8 mm) derived from phenolic resin have been developed and characterised. The results show that the surface polarity can be enhanced by potassium intercalation. The intercalation of potassium significantly increased the CO2 capacity of the AC beads by a factor of up to 2 at 0.15 bar while the effects of the treatment on their mechanical strength and morphological features were negligible at KOH/AC mass ratios of 0.3 and below. The factors other than adsorption that affect the performance of phenolic resin derived carbon spheres were also investigated in terms of adsorption kinetics, cyclic performance, heat of adsorption, the effect of moisture, and regeneration heat. Secondly, coal tar pitch derived activated carbons, with uniform spherical diameter of 1-2 mm were synthesised via two different activation approaches, which is firstly an initial steam activation followed by KOH activation, and secondly one-step KOH activation, both with mild KOH/carbon mass ratios. Samples prepared with one-step KOH activation method had shown a better microporous structure and a higher CO2 adsorption capacity. Owing to the narrow micropores and K-doping, the samples demonstrated outstanding CO2 capacities at relatively low CO2 partial pressure. Multicycle stability was examined over 50 cycles of adsorption and desorption, and both samples present excellent adsorption kinetics and regeneration ability. Finally, the volumetric CO2 uptake of best performing samples were also calculated and compared with other candidates. Based on our previous results, further investigation towards the influence of precursor materials and correlation between microporosity pore size ranging from 0.4 nm to 2 nm and CO2 uptakes have been carried out. Future work on how to improve the CO2 sorption performances of the studied materials has been proposed.

The presence and impact of steroid estrogens in natural water matrices has driven development and evaluation of wastewater treatment technologies that may reduce the steroid load entering water environments. This work was undertaken to assess and predict the ability of Trametes versicolor laccase to degrade estrone (E1) in water matrices under realistic conditions to wastewater treatment plants (WWTPs) and with consideration of the complex and variable nature of the wastewater matrix. A robust experimental procedure was developed to ensure the efficiency of the enzyme laccase to degrade E1 in water matrices was not overestimated due to errors arising from poor experimental design. These experiments demonstrated that commercially-obtained laccase in concentrations above > 1 mg/ml are inhomogeneous requiring centrifugation prior to use to reduce error and provide more accurate evaluation of laccase capability. Sample filtration, which is necessary for chromatographic analysis, identified regenerated cellulose (RC) membrane filters as the optimum filters for particulates removal from E1 solutions due to their low affinity toward E1 (3.2 ±1.72 %). An optimum enzyme inactivation procedure using hydrochloric acid was also developed to ensure that the enzyme laccase was instantly inactivated without affecting the target steroid E1 itself. Using the established experimental procedure, bench-scale studies evaluating the efficiency of laccase-based treatment in a ‘clean’ water matrix were investigated. Experiments in deionised water provided a proof of concept of laccase ability to degrade E1 in water under realistic ranges of temperature [6˚C - 25˚C] and contact time [0.5 hr – 8 hrs] to the WWTP and evaluate the use of models to fit experimental data and predict within that system. Box Behnken Design (BBD) was applied to determine the number and the conditions of the performed experiments. The experimental data was then utilised to build two different models to predict E1 removal efficiency under any set of conditions and optimise the performance of laccase-based treatment system. The goodness of the fit for each model was tested using statistical indices such as coefficient of determination (R2), mean squared error (MSE) and absolute average deviation (AAD). The artificial neural network (ANN) model showed a better fit to the experimental data than the response surface methodology (RSM) model (RSM and ANN of R2 = 0.9908 and R2 = 0.9992 respectively. In addition, the predictive capabilities of RSM and ANN were tested using a set of statistically designed unseen data that was not previously used in models’ training. Both models showed limited predictive capabilities. The ability of laccase-based treatment to remove E1 in real-world wastewater was studied at bench scale. To account for the complexity and variability of the wastewater matrix, effluent samples during the period December 2014 - June 2015 were characterised for standard water quality parameters, where the temporal variation in wastewater chemical oxygen demand (COD), total suspended solids (TSS) and pH, were observed. A new water quality parameter, “Benchmark” was also developed and applied to quantify the impact of wastewater variability on laccase performance for E1 removal. The average benchmark value in the period between December 2014 and June 2015 was 79.8±3.7%. In addition, the impact of laccase inhibitors, which are likely to be present within the wastewater matrix, such as chloride, copper, iron and zinc, on laccase activity was investigated. The inhibitory effect of chloride ions increased with increasing chloride concentration above 200 mg/l. Copper and zinc ions exhibited negative effects on the enzymatic degradation of E1 at concentrations equal or above 10 mg/l and 200 mg/l. The impact of water matrix temperature, contact time and laccase concentration were studied in wastewater effluent and the experimental data was used to build RSM and ANN models. The predictive capability of the generated RSM model was relatively poor (R2 = 0.863) and even lower than the achieved predictive capability in clean matrix when tested using unseen data, this was partially attributed to the variability of wastewater matrix that could have not been addressed in this type of models. Whilst the improved ANN model showed a better predictive capability than RSM (R2=0.991) An advantage of the ANN model compared to the RSM model and reported for the first time, was the ability to include the impact of matrix complexity and variability on laccase performance, assessed via the benchmark data added as a forth factor in the ANN model. The final ANN model incorporating the matrix variability observed temporally during the sampling period had extremely high predictive capabilities (R2 > 0.99). This model approach holds the potential to help researchers evaluate and optimise laccase-based treatment (as well as other treatment technologies) and predict the removal efficiency of various bioactive chemicals under a wide range of conditions. Performing laccase-based treatment in a continuous reactor, utilising actual wastewater effluent and under realistic conditions to WWTPs, is the next stage that should be investigated in detail.

A rise of 2 oC in the Earth’s temperature is likely to occur when the concentration of CO2 in the atmosphere reaches approximately 450 ppm. CO2 emissions are closely related to the continual use of fossil fuels. In order to make fossil fuels sustainable, carbon capture & storage (CCS) is required to reduce CO2 emissions. There are three leading CO2 capture methods, namely post-combustion capture, oxy-fuel combustion and integrated gasification combined cycle (IGCC) pre-combustion capture. CO2 hydrate (CO2:6H2O) formation has been investigated as a way to capture CO2 in the IGCC conditions. The formation of hydrate in this work was experimentally investigated in an isochoric system (batch mode) inside a vertical fixed bed reactor (FBR), also known as high pressure volumetric analyser (HPVA). Standard silica gel with an average particle size of 200-500 µm, mean pore size of 5.14 nm, a pore volume of 0.64 cm3/g and a surface area of 499 m2/g was used as a porous medium. The presence of hydrate in FBR was justified by using graphic methods. The solubility of CO2 in water using Henry’s Law and the experimental pressure–time (P-t) curve were analysed to determine the formation of hydrate. Hydrate formation was confirmed when the mole fraction of CO2 dissolved in water exceeded the Henry’s Law value as well as a two-stage pressure drop in the experimental P-t curve. Initially, various sample preparation methods (methods 1, 2, 3 and 4) were studied leading to the selection of method 4 (the use of vigorous stirring) which had the highest moisture content (14.8 wt%) and the greatest water conversion to hydrate (40.5 mol%) at 275 K and 36 bar in a pure CO2 gas system. Also, high regeneration and repeatability of the results for all samples prepared by method 4 were expected as less water was occluded inside silica gel pores. Further investigations in pure CO2 gas systems highlighted the effect of type of silicas used, the importance of the type of promoters used, the concentration of promoters, experimental driving force, silica pore size, bed height and the amount of moisture content for formation of hydrate. Standard silica gel was the only silica found to show hydrate formation due to the best distribution of pore size. The high amount of bulk water inside zeolites 13X and spherical MCF-17 (21.3 and 50.8 wt% respectively) was the main reason of no hydrate formation observed. Additionally, the combined-promoters designated type T1-5 (0.01 mol% sodium dodecyl sulphate (SDS) + 5.6 mol% tetrahydrofuran (THF)) and type T3-2 (0.01 mol% SDS + 0.1 mol% tetra-butyl ammonium bromide (TBAB)) were the two best obtaining a CO2 uptake of 5.95 and 5.57 mmol of CO2 per g of H2O respectively. Ethylene glycol mono-ethyl ether (EGME; 0.1 mol%) was a good alternative to THF when combined with SDS (0.01 mol%) with a CO2 uptake of 5.45 mmol of CO2 per g of H2O for this combined-promoter designated type T1A-2. In addition, the CO2 uptake increased as ∆P increased or ∆T decreased. Moreover, mesoporous silica (silica gel) performed better than microporous silica (zeolite 13X) where the formation of hydrate by zeolite 13X was observed with minimal CO2 uptake (0.58 mmol of CO2 per g of H2O) when the bed height was reduced. Additionally, the total amount of CO2 consumed through hydrate formation increased as the amount of water inside mesoporous silica increased which was not the case for microporous silica. Furthermore, the experiments performed in the IGCC conditions (283 K and 70 bar) by employing T1-5 and T3-2 in a fuel gas mixture demonstrated low hydrate formation with a CO2 uptake of 1.5 and 1.1 mmol of CO2 per g of H2O respectively. This was expected due to the slow kinetics since CO2 molecules were competing with H2 molecules which also reduced the selectivity of CO2 molecules during hydrate formation. Hence, in reality, pure CO2 system is the best option for CCS through hydrate formation at the right operating conditions as compared to fuel gas mixture.

Metal pollutants such as copper released into the aqueous environment have been increasing as a result of anthropogenic activities, a topic causing global concern. Adsorption-based treatment technologies offer opportunities to remediate metal pollutants from municipal and industrial wastewater effluent. The aim of this work was to evaluate the capability of modified cellulose nanowhisker (CNW) adsorbents for the remediation of copper from water matrices under realistic conditions using response surface methodology (RSM) and artificial neural network (ANN) models. The first part of the study explored the preparation and characterisation of modified CNW adsorbents. It also focused on the stability of the modified CNW adsorbents at different time intervals under dry conditions (up to 28 days) and in the water matrix (up to 7 days). The results showed that the modified CNW adsorbents were stable at different time intervals under dry conditions and in the water matrix and proved that the functional groups were permanent and did not degrade under the tested conditions. The stability of these modified CNW adsorbents under these conditions, which is relevant from both the manufacturing and application perspectives, is reported for the first time in this study. The second part of the work focused on using copper as a case study for heavy metal pollution in a clean water matrix, to evaluate removal by modified CNWs under several conditions and ranges appropriate to wastewater treatment plants (WWTPs), using factorial experimental design. RSM and ANN models were employed in order to optimise the system and to create a predictive model to evaluate the Cu(II) removal performance by the modified CNW adsorbents. Moreover, unseen experiments not belonging to the training data set, located both inside and outside the test parameter system, were performed to test the model suitability. This is also novel, as generally only one or two parameter variations have been tested, without checking the chosen model suitability for parameters lying between the tested parameters, and certainly not for parameters lying outside the tested parameter space, as has been done in this study. The results obtained showed that the ANN model outperformed the RSM model when predicting copper removal from a clean water matrix. The Langmuir andFreundlich isotherm models were applied to the equilibrium data, and the results revealed that the Langmuir isotherm (R2 = 0.9998) had better correlation than the Freundlich isotherm (R2 = 0.9461). Experimental data was also tested in terms of kinetics studies using pseudo-first order and pseudo-second order kinetic models. The results showed that the pseudo-second-order model accurately described the kinetics of adsorption. The third part of the work was aimed at gaining a deeper understanding of the complexity and variability of the wastewater matrix, including evaluating the impact of the wastewater matrix temporally on adsorbent performance to remediate copper pollutant from a real-world wastewater matrix. This study has demonstrated that the wastewater matrix composition, which is both complex and variable, has an impact on adsorbent capability and performance. A benchmark study was adopted as a ‘new’ water quality parameter to inform on the effects of the wastewater matrix (wastewater composition and its variability) on the modified CNW adsorbent’s capability to remediate copper from this matrix. Since the process of adsorption from wastewater is often complicated due to the variation in wastewater composition, results obtained from the benchmark experiments were included as one of the independent variables in ANN modelling, unlike in other optimisation studies. The performance of the ANN and RSM models was statistically evaluated in terms of coefficient of determination (R2), absolute average deviation (AAD), and root mean squared error (RMSE) on predicted experimental outcomes. The ANN model including the variability of wastewater composition fitted the experimental data with excellent accuracy and better prediction (R2 = 0.9963) than both the ANN model that did not include this variability (R2 = 0.9945), and the RSM model (R2 = 0.9409). The outcome of this study showed that by supplying the ANN model with the data obtained from the benchmark experiments as the fourth independent variable, it was possible to improve the predictability of the ANN model. Continuous flow experiments for remediation of spiked Cu(II) from the wastewater matrix were conducted. However, the physical structure of modified CNW adsorbents renders them unsuitable for use in column operation. Therefore, a more detailed study of the mechanical properties of CNW adsorbents would be necessary in order to improve the strength and stability of the adsorbents. This work has demonstrated that modified CNW are promising adsorbents to remediate copper from water matrices under realistic conditions including wastewater complexity and variability. The use of models to predict the test parameter system and account for matrix variability when evaluating CNW adsorbents for remediating Cu from a real-world wastewater matrix may also provide the foundation for assessing other treatment technologies in the future.

Membrane filtration and Advanced Oxidative Processes (AOPs) are among the most efficient and cost-effective methods employed in water purification. A system to integrate the two methods using photoactive colloidal particles was studied in this thesis, with the final purpose of overcoming membrane fouling, one of the main issues occurring in filtration processes. The production of nanostructured TiO2 microparticles through a simple and extremely rapid synthesis and an easy method to assemble a multifunctional coating, integrating inorganic particles on filtration membranes, were targeted as the most promising solutions from the technological and environmental point of view. The control of microwave-assisted heating applied to hydrothermal treatments, a relatively recent synthetic method, allowed the production of nanostructured mesoporous spherical TiO2 particles, bringing the synthesis to the minute scale, extremely rapid compared with conventional heating, and achieving products otherwise difficult to obtain without the help of surfactants or templating agent. The as-synthesised particles showed photoactivity under visible light, with rate of specific reactions (selective de-ethylation) 4 times higher compared with commercial photocatalysts. Furthermore, the particles were modified to extend the limited intrinsic absorbance of TiO2 in the visible light, with promising results given by formation of stoichiometric defects (in particular oxygen vacancies) through annealing under vacuum. This treatment allowed the achievement of comparable or even higher performance in photocatalytic degradation of rhodamine B with respect to commercial TiO2 photocatalysts, including Aeroxide P25, with degradation rate towards organic molecules (rhodamine B) of even 60-70% after 1 hours, compared to the 25% of P25. The production of a multifunctional coating for water treatment by integration of colloidal and nanometric TiO2 particles has been also studied. A simple technique to integrate TiO2 nanoparticles onto different substrate, in particular filtration membranes, was developed by simple electrostatic interactions involving the use of polyelectrolytes, water-soluble charged polymer forming organised layers when assembled in a macromolecular structure defined as polyelectrolyte multilayers (PEMs). Electrostatic assembly was applied as an environmentally friendly technique to anchor nanoparticles (P25) on different surfaces, transferring their properties to these. In particular, the application of TiO2 particles conferred hydrophilic and superhydrophilic to a relatively hydrophobic surface (Mylar) by controlling the multilayer assembly conditions, in particular the ionic strength of the polyelectrolyte solutions. The achievement of superhydrophilic behaviour on the treated surfaces, with contact angles below 15° on Mylar surfaces, and the possibility of removing fouled active layer from a membrane replacing it with a newly generated one can be both implemented as potential antifouling strategies in water treatment.