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Ganoderma lucidum spores (GLS) have attracted increasing attention for its versatile biological activities, particularly in cancer therapy. The resilient chitin bilayer of sporoderm is conventionally regarded as an obstacle in the exploitation of bioactive ingredients. Present study found that ethanol extract of broken GLS was able to inhibit cancer cells, however, water extract, especially medium extract (containing serum protein) from unprocessed GLS have also demonstrated anti-proliferative effects on cancer cells. The effectiveness of GLS extract on the inhibition of a series of human cancer cells, namely, osteosarcoma, neuroblastoma, myeloid leukaemia and breast cancer, has been compared, and DNA assays showed that the GLS extract is more efficient in inhibiting neuroblastoma but has less effect on osteosarcoma cell line. To overcome the limitations of the existing processing methods of GLS, the feasibility of sonication as a new way to break GLS has been tested. A series of processing parameters, such as sonication power and duration, have been compared to maximise the breaking efficiency. The preservation of bioactive components of GLS (e.g. polysaccharides and ganoderic acids) from sonication processing was revealed by Fourier Transform Infrared Spectroscopy (FTIR) and High Performance Liquid Chromatography (HPLC) analyses. In vitro study showed that sonication processed GLS were able to inhibit breast cancer cells, at dose and time dependent manner, particularly at low pH (6.5), favourable for cancerous cell growth. The inhibitory efficiency of sonication processed GLS on the growth of breast cancer cells was ranked the highest, compared with that of unprocessed GLS and commercially broken GLS. To preserve further the bioactive ingredients of GLS, broken GLS have been encapsulated with alginate by electrospraying (ES). The size of GLS encapsulated alginate (GLS/A) beads was found to affect the in vitro release profiles of bioactive ingredients of GLS, and can be controlled by varying the processing parameters (e.g. crosslinking time, infuse rates and applied voltage). A series of GLS/A beads with mean sizes ranging from 500 to 2500 µm have been produced by ES and the in vitro release profiles of GLS/A beads in simulated gastrointestinal mediums were found to be related to the pH, bead size and drying methods. In summary, an advanced method combining a customised sonication with ES has been developed by setting up a lab-scale production line from processing to encapsulation of GLS. This may pave the way to produce effective GLS products with desirable natural bioactive components for healthcare.

Deposition wax is one of the chronic flow assurance problems that continue to attract attention in the oil and gas field, particularly as the hydrocarbon explorations and productions in recent years move into a colder environment. The accumulation of the wax deposit in the pipeline reduced or interrupted the production, and in the worst-case completely clogged the pipeline, resulting in equipment failure or field abandonment. Although significant progress has been made in mitigating the problem, many questions about the full understanding of the factors and the physical process mechanisms of deposition remain unanswered. Predominant researches are being conducted in straight pipes. The impact of pipe curvatures such as pipe bends, elbows, and inclinations (found in production and transportation systems) on the increased severity of the deposition is not well studied, only very limited studies being reported. In this thesis, the deposition of wax was studied in a single-phase flow using a novel laboratory-scale flow loop accommodating three different pipe configurations: a straight pipe and curved pipes with 45° and 90° bends. Series of experiments were carried out using a crude blend with and without chemical inhibitor at different flow rates – under laminar (Qoil; 3, 5, 7 l/min) and turbulent flow (Qoil; 9, 11 l/min) conditions and at different ambient cooling temperatures of 10, 15, 25 °C (Tcool ≤ pour point temperature of the oil) and 30, 35, 40 °C (Tcool ≥ WAT of oil). The experimental period was varied from 2, 4, 6, 8 hours. Prior to the flow loop studies, three different waxy crude oil samples and four commercial wax inhibitors are screened and characterised through different standard techniques. The wax content of crude oil samples A, B,and C was found to be 12.05, 20.05,and 14wt%, n-paraffin distributions ranges from C15-C74, WAT and pour point respectively. Similarly, SARA (saturated/aromatic/resin/asphalte) fractions, wax appearance temperature, viscosity, pour point, and the colloidal instability index of the samples was obtained. A new wax inhibitor was developed by blending different fractions of commercial inhibitors improved the performance and transformed the needle-like or rod-like crystals structure of the oil samples into an agglomerate with small particles dispersed in the oil matrix. The flow loop studies showed that the rate of wax deposition without inhibitor is significantly higher in curved pipes than in the straight pipe. In horizontal flow study – the test section with 90° bends pipes produces the highest wax deposition rate compared to the straight pipe test section and a test section with 45° bends pipes. For instance, under a low case scenario (i.e. at Tcool, 15°C and Qoil, 5 l/min), around 22% of the wax deposition rate was seen in straight pipe test section after 2 hours compared to 36% and 43.5% of the wax deposition rate in test sections with 45° bend pipes and 90° bend pipes sections. This implies at the same conditions where the system experienced 0% wax deposition in the straight pipe it underwent 14% and 19% deposition, respectively, for the pipe with 45° and 90° bends. However, the severity of wax deposition in curved pipes simultaneous decreases with increasing coolant temperature and flow turbulence and vice versa. On the other hand, increase in elevation of the pipes, however, led to a more wax deposition; higher percentage of wax deposit was observed in 45-degree compared to 90-degree curved pipe. Therefore, contrary to some theory established in the literature, this research concluded that gravity settling mechanism plays a role in the deposition process alongside with other mechanisms. The study with the new blended inhibitor produced a significant reduction of wax deposition. At 1500-ppm and at a cooling temperature of 15°C, around 80% of the wax deposition problem could be reduced under a turbulent flow regime. At the same flow rate but at a relatively higher temperature of 25°C(i.e. pour point temperature), 100% wax prevention was reached even at a lower concentration (500-ppm). Whereas, in the laminar flow regime (e.g.7 l/min), 100% wax deposition prevention could only be achieved at the higher concentrations of 1000 and 1500-ppm at 30°C. On the other hand, the experimental results under different conditions were simulated with OLGA software. The predicted results are in good agreement with the experimental data, particularly in the straight pipe. Base on the flow loop design, a new correlation using pressure drop a relationship was developed for quantification of wax deposit thickness in curved pipes. Generally, the established model relates wax deposit thicknesses, with a bend angle of the pipes and pressure drop due to the wax build-up with reasonable agreements to the published data, especially at steady-state conditions.

The significant increase of carbon dioxide (CO2) into the atmosphere is alarming since the industrial revolution and this has resulted to prevailing environmental challenges such as global warming experienced in recent times. There is an urgency to reduce CO2 emissions to a sustainable level in order to prevent global warming and climate change. Several methods of reducing CO2 emissions have been identified. However, greener synthesis of organic carbonates such as 1,2-butylene carbonate (BC) and styrene carbonate (SC) through the utilisation of CO2 have been identified to be valuable chemicals in chemical industry. The utilisation of CO2 to produce value-added chemicals is considered as one of the promising technological advancements targeted at reducing CO2 emissions to a sustainable level. 1,2-Butylene carbonate and styrene carbonate are promising green chemicals, which find their applications in chemical and pharmaceutical industries. These organic carbonates exhibit excellent chemical properties and can be used widely as intermediates to synthesise other chemicals, electrolyte to power lithium batteries and fuel additives. The syntheses of 1,2-butylene carbonate and styrene carbonate using conventional approaches involve the use of phosgene, a toxic feedstock and produce acid waste, which is highly toxic and environmentally unfriendly. The application of solvent-free heterogeneous catalytic processes promote green processes and offer more sustainable process for the syntheses of organic carbonates. In this work, batch experimental studies have been conducted using several commercially available heterogeneous catalysts such as ceria and lanthana doped zirconia (Ce-La-Zr-O), ceria doped zirconia (Ce-Zr-O), lanthana doped zirconia (La-Zr-O), lanthanum oxide (La-O), zirconium oxide (Zr-O) and graphene oxide supported inorganic nanocomposites where graphene oxide (GO) has been used as a suitable support and metal oxide catalyst (Ce-La-Zr/GO) has been extensively assessed for the synthesis of 1,2-butylene carbonate and styrene carbonate. Ceria, lanthana, zirconia doped graphene nanocomposites (Ce-La-Zr/GO) have been synthesised using a new innovative approach known as a continuous hydrothermal flow synthesis (CHFS) reactor. Copper, zirconia doped graphene oxide (Cu-Zr/GO) and copper, zirconia oxide/graphene composite (HTR450) have been synthesised using conventional wet impregnation methods and assessed as suitable heterogeneous catalysts for the synthesis of 1,2-butylene carbonate via a facile direct route. These catalysts have been characterised using various analytical techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and Brunauer-Emmett-Teller (BET) surface area measurement. The use of a solvent-free heterogeneous catalytic process for the direct syntheses of BC and SC have been conducted in a high-pressure reactor. Various reaction parameters such as the effect of reaction temperature, CO2 pressure, reaction time, catalyst loading, and stirring speed have been investigated to achieve the optimum reaction conditions on the conversion of epoxides and yield of cyclic carbonates. The long-term stability of the heterogeneous catalysts has been evaluated by conducting reusability studies. Copper, zirconia doped graphene nanaocomposite catalyst (HTR450) and ceria, lanthana, zirconia doped graphene oxide catalyst (Ce-La-Zr/GO) have been found to be the most active and selective for the synthesis of BC as compared to other commercial catalysts evaluated in this research work. For the direct synthesis SC, ceria, lanthana doped zirconia (Ce-La-Zr-O) has been found to be the best-performed catalyst as compared to other used catalysts. The reusability studies of these HTR450, Ce-La-Zr/GO and Ce-La-Zr-O catalysts have evidently shown the long-term stability without any significant reduction in their performances. Response Surface Methodology (RSM) in the design of experiment is used for modelling and optimisation of experiments in the process industry, catalysis and chemical reaction engineering. The application of RSM minimise the number of experiments thereby saving time and materials. Hence, RSM using box-Behnken design (BBD) has been explored to evaluate and optimise multiple responses (output variables), which are influenced by several independent variables such as catalyst loading, temperature, CO2 pressure, and reaction time. BBD model has been developed for the direct synthesis of SC via cycloaddition reaction of CO2 to styrene oxide (SO) and direct synthesis of BC through reaction of butylene oxide (BO) and CO2. The developed models have been used to compare the experimental results and the predicted results. Regression analyses have been carried out to establish the optimum reaction parameters for a maximum yield of SC and BC. The predicted values of BBD model are in good agreement with the experimental results with < 1.5% error.

The phenomenon of ‘inclusion’ in emulsions refers to the inclusion of continuous phase into the dispersed phase drops and formation of multiple drops due to the tendency of the inner phase to stabilise the outer phase. Inclusion plays an important role in both catastrophic phase inversion (CPI) emulsification process and preparation of multiple emulsions. In CPI, inclusion leads to formation of abnormal multiple drops, which eventually invert to the opposite desired normal emulsion. On the other hand, in multiple emulsions, inclusion may have an adverse effect leading to instability of the multiple emulsions because of coalescence of inner drops, and/or coalescence of multiple drops, or even bursting of multiple drops. All these result in instability of multiple emulsions and accelerate release of the active agent. In the first part of this work, we carried out a comprehensive study on the rate and extent of inclusion in CPI emulsification at different formulation and process conditions for the first time. We also investigated the conditions under which the CPI emulsification method produces finer emulsions than the direct emulsification method, which means applying less energy could result in a finer emulsion. In the second part of this work, we investigated the conditions under which inclusion can be ignored during the preparation of multiple emulsions. We also carried out an extensive study on the optimisation of the process conditions to achieve maximum encapsulation efficiency in freshly prepared multiple emulsions. In the last part of this work, we briefly looked at the possibility of synthesis of macroporous alginate hydrogel particles via CPI and through inclusion of an oil into sodium alginate drops but without success. However, we introduced a new modified emulsification process based on addition of calcium chloride water-in-oil emulsion to sodium alginate emulsion, which produced promising results.