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Abstract The water drained through the sewage network and petroleum traps to natural water sources contains a large amount of petroleum products, salts, reactants released, hydrogen sulfide and various types of bacteria and other impurities. The discharge of petroleum industrial water leads to severe water pollution, and to a significant reduction in the percentage of dissolved oxygen in the water, which leads to the death of fish and the poor health conditions of the residents of the neighboring residential areas. Sources are not useful for washing or drinking purposes, but for production purposes as well. Moreover, with industrial wastewater, material valuable is lost, which is petroleum. Therefore, combating the loss of petroleum materials with industrial wastewater, as well as desalination and purification of this water is a matter of social and economic importance. This thesis deals with the membrane desalination of water pollution resulting from the different stages of the petroleum industry (exploration, drilling, production, refining, transportation and storage) as: water pollution includes all water sources on the surface of the earth, whether fresh water or sea water, such as: seas, rivers, oceans and groundwater. In addition to the nanocellulose and the capsule that was used as a filler in the membranes, several membranes were prepared mainly based on polyethersulfone as a support layer, a layer of polyamide (needed for the desalination process), and nanomaterial’s. The membranes were prepared using the solvent phase separation process of the polymer, while the activated carbon thin film (ACTF) were prepared from cotton, and the nanocellulose was obtained using the hydrolysis method of agricultural waste. Composite membranes were prepared to form the three types of membranes that were used in desalination of water from the petroleum sector, as follows: • A polyethersulfone based membrane (TFC). • A polyethersulfone TFC membrane containing nanocellulose/activated carbon thin film TFC@ACNCE membrane. • A polyethersulfone membrane containing the microcapsules, which consist of poly (urea formaldehyde) CPUTFC membrane.The characterization tools used to characterize the prepared nanomaterial’s and composite membranes in this thesis includes the following: XRD- spectroscopy, FTIR, Raman Spectroscopy, Contact Angle, Atomic Force Microscope (AFM), Scanning electron Microscope (SEM), Transmitting electron Microscope (TEM), Thermal Decomposition Measurement (TGA), Zeta potential, as well as swelling measurement , wettability measurements and mechanical properties of the prepared membranes. By characterizing the prepared nanomaterial’s and membranes using Raman and FTIR, the chemical structure and specific functional groups for each nanomaterial’s and membranes were proven. Also, through the use of XRD spectroscopy, the crystal structure of the prepared nanomaterial’s was revealed, as it appeared that the prepared ACTF have a hybrid nature as it contains graphene oxide sheets in combination with activated carbon with crystalline size of 55-85 nm .It was also found that the prepared nanocellulose has a specific crystalline nature with the size of 55 nm. Through scanning electron microscope analysis, it has been proven that these membranes surface changing from smooth to rough surface nature in the presence of nanomaterial’s, and it shows that the capsules have a specific appearance and size ranging between 40 to 60 µm, as well as the membranes containing ACTF showed that its size ranged from 50 to 100 nm. Through the result of thermogravimetric analysis (TGA) to test the thermal stability of nanomaterial’s and composite membranes TFC, TFC@ACNCE and CPUTFC, the thermal stability of the TFC @ ACNCE membrane more stable than the TFC, and CPUTFC membranes, which in turn expands the industrial application fields of the prepared membranes. The membranes prepared in this thesis were evaluated by studying both the efficiency and the durability of the membranes to harsh conditions of pressure and heat in addition to studies of time and pH with studies on the concentration of salts in the produced water and retention water in addition to calculating the amount and concentration of salts that were reserved in the best conditions for the work of these membranes in the desalination of water in the petroleum fields.Through this study which proved that the TFC@ACNCE membrane is capable of desalinating water, as it gave the highest salt retention rate of 91% at a pressure of 90 bar compared to the TFC membrane, which gave a retention rate of 79% at pH 13 and after 7 hours it gave a retention rate 72.4%. As for the capsule, it gave a retention rate of 78% for salts at a pressure of 90 bar and a temperature of 55C. The study of membrane wettability or swelling also showed that the adsorption process is important in the self-healing mechanism to understand the penetration of mobile ions in the feed water, resulting from the driving force of the potential chemical interaction with ions and the impeded nanomaterial’s of composite membranes. The TFC showed a low degree of swelling compared to the other composite membranes, whether TFC@ACNCE and CPUTFC membranes. This indicates that the TFC@ACNCE membrane has higher water permeability with higher ion-rejection efficiency compared to both the TFC and the membrane containing microcapsule, which is related to the chemical composition of the component of membrane structure. The TFC@ACNCE membrane’s retention rate of salt and inorganic contaminants increases from 60 to 96%. Therefore, we can say that the TFC@ACNCE membrane have a higher resistance to antifouling than the TFC membrane due to the hydrophilic structure of forming coordination bonds and ion exchange with the ions present in the feed water of the composite membranes. The TFC@ACNCE composite membrane containing 0.01 wt% ACTF exhibited anti-scaling properties as well as lower water permeability during measurement tests compared to other membranes. The high adsorption capacity of TFC @ ACNCE towards calcium ion is due to the adsorption sites, including the bonding of the carboxyl group -COOH, -NH group, -NH group, and -OH hydroxyl groups.The prepared membrane TFC@ACNCE offers a high rejection rate and high fouling resistant. During the damaging process of the TFC@ACNCE membrane, the original membrane quality can be restored through the self-healing process, this extending the life time of the TFC@ACNCE membrane in comparing with other membranes. In addition to the scaling resistance experiments on TFC and TFC@ACNCE, CPUTFC membranes, this provided the superiority of the TFC@ACNCE membrane over the rest of the membranes in preventing the formation of inorganic scale and stabilizing the flow rate and ion rejection. The mechanical properties of TFC@ACNCE membrane can be attributed to the uniform distribution of ACTF sheets in the polysulfone matrix, watching benefiting from the interconnected 3D porous network structure of the ACTF aerogel type used and the good interface adhesion in the face of both inorganic and organic contaminants in comparing with other two membranes. TFC@ACNCE as a good structural desalination membrane for self-healing in the future. |