The purpose of this study was to develop adsorbents from slag materials as a low cost method to purify acid mine drainage of high acidity and toxic metal ions content. The study included adsorbent characterisation and adsorption experiments to understand the adsorption behaviour of a multi-adsorbate system of Cd\(^2\)\(^+\), Co\(^2\)\(^+\), Cu\(^2\)\(^+\), Fe\(^2\)\(^+\) and Mn\(^2\)\(^+\) ions. It was found that the adsorbents had low surface area and unfavourable pore size distribution. The chemical activation of the adsorbents improved the adsorbent properties, and thus increased amounts of metal ions adsorbed. However, the adsorption of multiple metal ions was only effective in dilute solutions, with adsorption efficiency increasing with increase in phase ratio, pH and temperature. The adsorption data was best described by pseudo second order kinetic and double exponential diffusion models. The mechanisms involved adsorption, precipitation and ion exchange. The adsorbent capacities were relatively low, with selectivity proposed as Fe\(^2\)\(^+\)>Cu\(^2\)\(^+\)> Cd\(^2\)\(^+\)>Co\(^2\)\(^+\)>Mn\(^2\)\(^+\). The fixed bed efficiencies were satisfactory but the adsorbents were easily exhausted, which indicated a limited ability for the adsorbent materials to be regenerated. However, desorption of metal ions was favourable, and this may provide an opportunity for metal ions to be recovered and for spent adsorbents to be disposed safely.

The availability of finite resources is uncertain due to the worldwide increase in population growth and global industrialisation. Consequently, there is a pressing need for substitutive replacements and methods of replenishing stocks by recycling. The platinum group metals (PGMs) are rare, expensive elements with an unpredictable supply chain and a wide range of industrial applications for which there are often no substitutes. Mining from primary ores is environmentally damaging; hence recycling is vital to minimise losses and maintain stock at sustainable levels. This work investigates the feasibility of recovering PGMs from secondary waste sources and bioconverting them into new catalysts, circumventing the current environmentally polluting and energy expensive pyrometallurgical processing. Two secondary sources of PGMs were examined: scrap automotive catalysts and spent furnace refractory lining. This study shows a route to improve PGM recycling from secondary waste sources and, further, the potential to produce a catalytically active end product without the need for traditional refining.

Mechanically agitated vessels are widely used for various mixing operations within a wide range of industries including the chemical, pharmaceutical, food and petroleum industries. They are used for liquid blending, solid-liquid mixing, gas dispersion in liquids, heat/mass transfer enhancement and chemical reaction. Mixing is intrinsically a Lagrangian process and, whilst Eulerian data are essential, Lagrangian information is necessary for its complete description. Possible approaches of generating Lagrangian data can, in principle, employ numerical simulations or experimental techniques based on Lagrangian tracking to provide the trajectories of fluid elements or solid particles. In this work a set of tools are developed for the analysis and theoretical validation of Lagrangian single and multi-phase flow data obtained from tracer trajectories in mechanically agitated vessels. Whilst theoretical procedures developed here exploit a large range of mathematical and statistical concepts with Shannon entropy being an example, the computational data analysis often involved handling and sequential processing of multidimensional matrices containing several millions of data points. Computational codes were developed for performing Lagrangian statistical data analysis, Lagrangian-Eulerian data conversion, Shannon entropy analysis, multi-phase mixing studies and detailed Eulerian multi-plane investigations. The implementation and power of these tools are demonstrated by analysing a wide range of measurements acquired using the technique of positron emission particle tracking (PEPT) during the mixing of Newtonian and non-Newtonian fluids, as well as the mixing of highly concentrated solid-liquid systems. These multi-phase suspensions included monodisperse, binary and polydisperse solid-liquid suspensions. Experimental measurements obtained in these systems are unique and valuable in their own right as, for the first time, it has been possible to determine the full 3D velocity and concentration fields of liquid and solid phases within opaque dense slurries of this type containing up to 40 wt% solids.

It is proposed that Ionic Liquids offer a new opportunity for exploration into a novel medium for processing Active Pharmaceutical Ingredients, particularly with respect to habit control and polymorphic form. A review of relevant literature relating to ionic liquids properties, commercial applications and current research has been summarised together with background into fundamental crystallisation theory. Crystallisations using thermal methods were employed at laboratory scale and the physical properties of the resultant powders were analysed and compared to commonly encountered crystal forms. For paracetamol it was found that the morphology of the crystals could be manipulated, producing in some cases, habits not reported for conventional organic solvent crystallisation. This was achieved through changing both the IL used and the saturation of the system whilst in all cases retaining the most stable polymorph. ILs ILs to be ‘designed’ for a given API but greater understanding of the interactions between IL and solute are required first. Properties such as increased solvation power, thermal stability, liquidus range and low vapour pressure bring a number of advantages when designing industrial crystallisations. However ILs also have a number of disadvantages including phase separation problems.

The objectives of the research presented in this thesis were: (1) optimise the processing conditions for the production of water-in-cocoa butter emulsions; (2) understand the role of water droplets on the large deformation behaviour and crystallisation properties of emulsified systems. Results showed that a scraped surface heat exchanger could be used to produce tempered emulsions with a small average droplet size (~3 µm). In all systems stability was provided by the emulsifier and fat crystals forming a network both in the bulk and at the interface of the water droplets. Characterisation of the large deformation properties of emulsions showed that the elastic behaviour remained constant at low aqueous phase percentages while the strength at fracture decreased. This result suggests that water droplets act as stress-concentrator elements, which is probably due to their partial sintering with the bulk network. Results of crystallisation experiments have shown that the effect of droplets on kinetics of crystallisation depends on the degree of supercooling: only at relatively high temperatures (15, 20 °C) the dispersed droplets increased the kinetics of crystallisation compared to bulk cocoa butter (CB). With respect to polymorphic evolution, emulsified systems evolved faster toward more stable forms than bulk CB at all temperatures.

Soybase is the aqueous extract produced directly from whole soybeans. Its main processing steps include milling, solubilisation, separation of solids, and heating. During this process, the waste stream okara produced typically contains 80% moisture and a considerable fraction of protein. A novel extraction model highlights this role of okara for the first time. Availability of protein and separation efficiency were identified as limiting factors of extraction through microstructure visualisation of the processing materials by a novel confocal laser scanning microscopy (CLSM) study. Ultrasound treatment of soy slurry and okara improved the protein extraction yield at lab-scale via enhanced solubility and to a less extent separation efficiency. Performing scale-up investigations showed a reduction in ultrasonic effects at pilot-scale due to higher energy intensities and reduced protein insolubility. Another cavitation technology explored was high pressure homogenisation (HPH). In contrast to ultrasound, HPH disrupted cells resulting in a better extraction assistance that should be explored further at pilot-scale. The work presented in this thesis provides the reader with an overview of the challenges faced during aqueous protein extraction from whole soybeans and novel routes for process intensification.

The preparations of SEC/IEC supports from commercially available, underivatised base matrices by AGE activation-partial bromination technique via two different approaches; (i) viscosity enhanced-reaction diffusion (VE-RD) and (ii) microwave-assisted reaction diffusion, were studied and optimised. Selected supports produced by both approaches were further evaluated by applying to packed bed chromatography system in order to purify target pDNA from neutralized E.coli cleared lysates.For VE-RD approach, viscosity enhancement by sucrose (< 0.032 Pa.s) was found to greatly aid the creation of thin inert outer layer. The optimum condition for SEC/IEC Sepharose CL-6B production observed was 10% single bromination at room temperature in 64% (w/v) aqueous sucrose without sodium acetate addition. The effects of different base matrices, conductivities, linear flow rate, target pDNA sizes and support preparations on chromatography performance were investigated. Microwave irradiation heated up the reaction in a rapid controlled manner compared to conventional heating. SEC/IEC Sepharose CL-6B produced via microwave-assisted reaction diffusion approach at 80oC with 10% partial bromination showed almost complete surface charge elimination with the highest SI value of 57.4. This support showed the high core binding capacity. However, a delayed pDNA breakthrough was also observed. It was noted that the plasmid forms remain unchanged after SEC/IEC column purification.

2,5-dimethylfuran (2,5-DMF) has gathered interest as an energy-dense compound with similar fuel properties to gasoline. This thesis describes the catalytic hydrogenation of 5-hydroxymethylfurfural to 2,5-dimethylfuran, employing three different hydrogen donor sources (molecular H\(_2\), mixture of formic acid/triethylamine and 2-propanol). Transmission electron microscope analysis showed that the bio-Pd synthesised by D. desulfuricans were generally larger than both the monometallic Bio-Ru and bimetallic Bio-Pd/Ru synthesised by B. benzeovorans. Under optimised conditions in molecular H\(_2\), 5 wt% Ru/C catalyst achieved 95.1% 2,5-DMF yield in 2 hours; in contrast the 20 wt% Bio-Ru/Pd gave 60.3% yield of 2,5-DMF at identical conditions. Transfer hydrogenation of 5-HMF to 2,5-DMF was investigated over Ru/C catalyst in formic acid/triethylamine mixture achieving 92.1% 2,5-DMF yield in 4 hours at 210 \(^o\)C and 5:2 molar ratio. It is interesting to note that 56.7% 2,5-DMF yield was achieved using the 20 wt% Bio-Ru/Pd catalyst at identical conditions. Transfer hydrogenation of 5-hydroxymethylfurfural in 2-propanol was studied over 5 wt% Bio-Ru/Pd catalyst and 42.6 2,5-DMF yield was obtained at 260 \(^o\)C after 2 hours of reaction time. It is concluded that hydrogenation of 5-HMF in molecular H\(_2\) offer superior advantages to transfer hydrogenation in HCOOH/Et\(_3\)N mixture and 2-propanol in terms of product yield and selectivity.

Thermal energy storage (TES) has a crucial role to play in conserving and efficiently utilising energy, dealing with mismatch between demand and supply, and enhancing the performance and reliability of our current energy systems. This thesis concerns TES materials and devices with an aim to establish a relationship between TES device level performance to materials properties. This is a multiscale problem. The work focuses on the use of carbonate-salt-based composite phase change materials (CPCMs) for medium and high temperature applications. A CPCM consists of a carbonate salt based phase change material (PCM), a thermal conductivity enhancement material (TCEM, graphite flake in this work) and a ceramic skeleton material (CSM, MgO in this work). Both mathematical modelling and experiments were carried out to address the multiscale problem. The wettability of carbonate salt and MgO system is first studied, followed by exploring the CPCMs microstructure characteristics and formation mechanism, and then the effective thermal conductivity of the CPCMs is carried out based on the developed microstructures. At the last part, heat transfer behaviour of CPCMs based TES at component and device levels is investigated.

Water-in-Oil emulsions present a potential strategy for fat reduction in conventional baking margarine (and thereupon bakery products), by replacing a portion of the fat with a water-based fat mimetic. Using hydrocolloids, polymers, and stabilisers, this aqueous phase may be structured in such a way as to emulate the physical and mechanical behaviour of the fat, but with almost none of the associated energy contribution - presenting potential for a realistic, marketable solution towards weight management and calorie control. This work has adopted a holistic strategy in order to characterise and understand the various structural components and processes consolidating to form a final, optimized, baking margarine emulsion structure. The relationship between the microstructure and the physicomechanical properties of standalone structured aqueous hydrocolloid phases is studied, and modelled for more complex systems. Emulsification processing parameters were optimized for production of water in palm oil baking margarine emulsions, before then applying these learnings for successful formulation of reduced fat palm oil emulsions incorporating the structured aqueous phase. A conventional margarine process is optimised for a contemporary role of emulsification to successfully create fully emulsified 30% reduced fat baking margarine emulsions, with potential for considerably higher aqueous phase fractions depending upon particular baking application.