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A refinery consists of crude oil operations, unit operations and product blending Operations. In crude oil operations the refinery deals with availability of crude oil and crude oil inventory management. Whereas, product blending deals with the fluctuating market requirement of the blended products. In the whole process the demand flows towards the suppliers, whereas the product flows towards the customers. However, because of volatile raw material prices, fluctuating product demands, quality improvement acts and other changing market conditions, it is difficult to have stable profit margins. In this work, we have covered refinery planning under market uncertainty, flexible scheduling of oil inventory management and the molecular level management for refinery gasoline blending in order to improve refineries competitiveness.

An area of industry that exploits zeolites for separation purposes is that of the petroleum industry where zeolites are used in catalytic conversions as well as chromatographic separations of hydrocarbons. The development of large pore sized materials such as MCM-41 enables larger molecules to be separated by the process of size exclusion than by traditional zeolites. In this work, mesoporous materials were synthesised and characterised using powder x-ray diffraction and nitrogen surface studies and shown to have different pore sizes in the region of 2 nm to 6 nm. They were then compared to traditional size exclusion gels and zeolites for their ability to sorb overbased and neutral sulphonate and phenate detergents, which were Soxhlet extracted from base oil, characterised by infrared spectroscopy and the results used to predict possible separations of binary detergent mixtures. The sorption properties of the mesoporous and silica gel materials were determined as follows: - (i) batch slurry sorption uptake to determine the maximum amount of detergent adsorbed within the pores of the material which showed an uptake of neutral sulphonate in the range of 0.12 to 0.37 g/g of mesoporous material and neutral phenate in the range of 0.11 to 0.30 g/g of mesoporous material with the uptake apparently increasing with pore diameter and aluminium content. Only surface adsorption occurred on the silica gel materials in the range of 0.3 to 0.6 gig of silica gel. (ii) The materials were prepared as liquid chromatography columns which showed that the neutral detergents were retained by the mesoporous materials and not the silica gels whereas the overbased detergents were not retained within the pores of either type of material. (iii) Using the mesoporous materials as the packing in gas chromatography columns to determine the heats of adsorption of molecules which were constituents of the detergent molecules investigated. It was found that the heat of adsorption of alkyl chains were twice as large for the MCM than for the silica gel materials for example, dodecane with a heat of adsorption in the range of 101 to 111 KJ/mol on the mesoporous materials and in the range of 44 to 47 KJ/mol on the silica gel materials. The data also showed that very polar compounds such as phenol were completely retained by the columns suggesting strong interaction with the silicate material. The sorption data was then applied to the column separation of a series of overbased and neutral detergent mixtures where it was found that the neutral detergents entered and adsorbed in the iii bstract mesoporous materials whereas the overbased sulphonate was completely excluded from all the mesoporous materials and the overbased phenate adsorbed on the external surfaces of the 4 nm and 6 nm materials. The mesoporous materials were therefore able to separate the detergent mixtures whereas the silica gel materials failed to separate any of the detergent mixtures. The detergents were characterised primarily by infrared spectroscopy and the equilibrium established between the neutral detergent monomer and the overbased micelle was investigated by radiochemical labelling of the neutral sulphonate and measured using liquid scintillation techniques. The results of the equilibrium studies using radioactive neutral sulphonate suggested that exchange had occurred. The sorption uptake of radioactive neutral sulphonate determined using the liquid scintillation technique was found to be in agreement with the uptake value determined by infrared spectroscopy of 0.21grams per gram of material.

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More than half of platform petrochemicals are aromatic, whereas the only large-scale, naturally-occurring, renewable source of aromatics is lignin. Chemical depolymerization of lignin requires extreme conditions, and results in extensive destruction of the aromatic rings and/or char formation. By contrast, enzymatic lignin depolymerization occurs under mild conditions with retention of the aromatic nuclei. Therefore, laccase from Agaricus bisporus (LAB) and from Trametes versicolor (LTV) with the mediator, ABTS (2,2'-azino-bis(3 ethyl benzthiazoline-6-sulphonic acid)) were used to depolymerize lignin (sodium Iignosulphonate) under mild reaction conditions with the aim to obtain high concentrations of value-added chemicals. The depolymerization in the presence of LTV was higher than LAB, which resulted from the high catalytic activity of LTV. Lignin degradation resulted in formation of complex product mixtures. Therefore the products were fractionated and analyzed by different analytical techniques including GPC (for preliminary screening), HPLC and GCMS (for product characterization and quantification), and NMR (for fingerprint analysis). Products included guaiacol, vanillin, acetovanillone, vanillic acid, homovanillyl alcohol, phenol, 4- methyl benzaldehyde, catechol, p-toluic acid, 4- hydroxybenzaldehyde, tyrosoI, isovaniIIin, and 3-hydroxy-1-(4-hydroxy-3 -methoxyphenyl) propan-1-one, and the total yield of monomers from lignin was 9.8 % in the presence of LTV. The parameters involved in the depolymerization process were optimized to increase the yield of monomers. The efficiency of laccase mediators was also explored by the use of 2,2,6,6-tetramethylpiperidin-1-yloxy (TEMPO), 1-hydroxybenzotriazole (HBT), N-hydroxyphthalimide(HPI) and violuric acid (VLA) in the depolymerization of sodium lignosulphonate. However, the catalytic depolymerization in the presence of these mediators was lower than ABTS. In order to improve the solubility of the substrate for the depolymerization process, screening of ionic liquids that are compatible with LAB was deployed in order to find laccase-friendly ionic liquids for further use in lignin depolymerization. The study has found [C4mim] [L-tartrate] as the best ionic liquid tested, that increased the activity of LAB by 90 %. In conclusion, enzymatic depolymerization of lignin offers a greener process than the chemical methods, and also provides a more efficient method to obtain monomers of valuable specialty chemicals under mild reaction conditions.

Mankind makes extensive use of crude oil to fuel its insatiable demands for energy and hydrocarbon derivatives. The refining of crude oil is based on a process known as cracking, where long-chain hydrocarbons are systematically broken into smaller chain hydrocarbons known as fractions with each fraction allowing for the production of a specific material. The maximum efficiency of cracking can be achieved in the petroleum refining processes by controlling the operating parameters of the units, and over the years many studies have attempted to optimize the cracking conditions such as temperatures, pressures and the use of a variety of catalysts to reach maximum productivity. Catalysts such as the Y-type zeolite catalysts are often used because their acidity and thermal stability makes them an ideal cracking catalyst; however the developments of enhanced catalytic properties for zeolite-Y catalysts are essential to increase the production yields. Optimization of the Y-type zeolite catalyst is the focus of this research and accordingly the synthesis, characterization, modifications and catalysis have been studied in depth. A review of the literature has shown that there are three main techniques used to improve the zeolite properties following the synthesis process; (Cation exchange, Dealumination and Desilication), since the crystalline structure of a Y-type zeolite is prepared from an alkaline aluminosilicates gel. However, the literature focuses mainly on the reaction variables used in the modifications. As such this study focuses on the effects of treatment processes on the composition, behaviour and catalytic properties of the synthesized Y-zeolite framework. Laboratory experimental data has confirmed that a synthesis process using 24 h aging for crystal nuclei at 25 °C and 18 h crystallization time for crystal growth at 100 °C produced the desired zeolite NaY morphology, and NaNH4Y zeolite forms with various cation contents (3, 1.5 and 0.5 wt% Na+) were obtained by subjecting the NaY form to a multi-stage ion exchange using 0.5 M NH4NO3 at 80 °C, while the HY form was obtained by the calcination of NH4Y form under high temperature. Calcination temperatures above 450 °C were shown to indicate a removal of the framework hydroxyl groups via dehydroxylation, which led to a collapse of zeolite-Y structure, whereas raising the level of Na+ inside the zeolite lattice throughout the calcination was led to a delay in the starting point of the dehydroxylation region as confirmed via TG and DSC-analyses. This finding was also used in the preparation of the USY form by steaming the HY form, as the former is a traditional zeolite-Y form utilized in the refining units. It was found that Na-ions hindered the extraction of Al-atoms from the Y-lattice thus reducing the rate of dehydroxylation, and minimising rapid contraction of the unit cells and Y-structure collapse, which helped make a rigid structure and a more resilient lattice for steaming at high temperature. In addition, analyses data confirmed that the extraction of EFAl-species from the USY-structures using an EDTA chemical treatment led to an increase in the acidity of treated catalyst and the introduction of mesopores. Lower lattice Si/Al ratio and larger porosity were also found using the dealuminated-desilicated rather than the desilicated-dealuminated leaching method in the treatment of both Y and USY structures via dislodgement of both Si and Al-atoms in NaOH and HCl solution. Cracking was performed on deactivated catalysts (450 °C) in a PFTR using nC7 in N2 at 325 - 425 °C and W/F = 22 - 44 g.h.mol-1, and confirmed that the tuned steaming/leaching conditions succeeded in modifying the catalytic properties of the in house made catalysts, as they possess superior performance when compared to the industrial catalysts typically used.

The history of crude oil desalting/dehydration plant (DDP) has been marked in progressive phases-the simple gravity settling phase, the chemical treatment phase, the electrical enhancement phase and the dilution water phase. In recent times, the proper cachet would be the control-optimisation phase marked by terms such as "DDP process control", "desalter optimisation control" or "DDP automating technology". Another less perceptible aspect, but nonetheless important, has been both a punch listing of traditional plant boundaries and a grouping of factors that play the essential roles in a desalting/dehydration plant (DDP). Nowadays, modelling and optimising of a DDP performance has become more apparent in petroleum and chemical engineering, which has been traditionally concerned with production and refinery processing industries. Today's desalting/dehydration technology finds itself as an important factor in such diverse areas as petroleum engineering, environmental concerns, and advanced technology materials. The movement into these areas has created a need not only for sources useful for professionals but also for gathering relevant information essential in improving product quality and its impact on health, safety and environmental (HSE) aspects. All of the foregoing, clearly establishes the need for a comprehensive knowledge of DDP and emulsion theories, process modelling and optimisation techniques. The main objective of this work is to model and qualitatively optimise a desalting/dehydration plant. In due course, the contents of this thesis will cover in depth both the basic areas of emulsion treatment fundamentals, modelling desalting/dehydration processes and optimising the performance of desalting plants. In addition, emphasis is also placed on more advanced topics such as optimisation technology and process modifications. At the results and recommendation stage, the theme of this work-optimising desalting/dehydration plant will practically be furnished in an applicable scheme. Finally, a significant compendium of figures and experimental data are presented. This thesis, therefore, essentially presents the research and important principles of desalting/dehydration systems. It also gives the oil industry a wide breadth of important information presented in a concise and focused manner. In search of data quality and product on-line-improvement, this combination will be a powerful tool for operators and professionals in a decision support environment.