الفهرس 
CHAPTER 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The price of crude oil has risen significantly as a result of the global depletion of light crude oil (LCO) reserves and the decreasing availability of conventional crudes, especially in developing countries. In this case, LCO refers to oil with a lower viscosity than heavier crude oil (HCO) with a higher viscosity. Impurities such as metal cations, sulfur, and asphaltenes are present in higher concentrations in HCO, making processing of these crude oils more difficult and, as a result, the oil itself less desirable. In addition to polluting crude oil, impurities pose a disposal issue for the atmosphere and human health.
The environmental pollution caused by heavy metals is determined by the toxicity and concentration of each metal in crude oil. Metals in high concentrations in water and soil can affect land animals, aquatic animals, and plants, disrupting delicate ecological balances and contaminating food supplies.
By minimizing viscosity and eliminating impurities, traditional hydro-treating methods use various catalysts and hydrogen sources to accelerate the refining process and improve the value of the crude oil. Vanadium, nickel cations, and other metals released when the asphaltenes molecules in the crude oil break down will poison the catalysts, which are the most active component in the process. The poisoning mechanism is caused by the metals (vanadium and nickel cations) binding irreversibly to the catalysts, reducing their potency over time.
Complexation, reverse osmosis, ultrafiltration, adsorption, solvent extraction, and ion exchange are all popular methods for removing metal ions from solution. Because of the simplicity of the application, metal ion exchange from aqueous solutions with ionic species in a solid matrix is an appealing side choice among these methods. Although a variety of materials, such as resins, can be used for ion exchange on a small scale, zeolites and clay materials are used on a large scale to exchange metal cations.
High sulfur content in crude oil has a negative effect on the refining process due to corrosion issues in pipelines and refining equipment, as well as its negative environmental impact. Desulfurization through solvent extraction, adsorption, photo-oxidation, and ionic liquid is the hydro-desulfurization process. Adsorption, which uses different adsorbents to desulfurize, is the most promising method. An efficient adsorbent must have an active surface, a large surface area, and a uniform pore size distribution.
NORM from the 232Th, 238U, and 40K sequence, on the other hand, are often enhanced as a result of industrial operations; these materials are officially known as Technologically Enhanced Naturally Occurring Radioactive Materials (TENORM). Since uranium and thorium are relatively insoluble or have low mobility, they will not be leached and will remain in the oil formation. Radium, on the other hand, is more soluble or mobile, and can be leached from the oil reservoir rocks into the water formation, which is present alongside the petroleum in the reservoir, under some physical and chemical conditions.