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Abstract Most of the Arab countries suffer from a severe shortage of clean water for drinking or agriculture. Egypt has approached the stage of water poverty that requires serious research and real attempts to overcome this serious problem. It has now a well-established fact that human health and the well-being of communities was totally linked to the health and integrity of their ecosystems. The World Health Organization stated in its 1997 report on the state of health and the environment that poor environmental quality and ecosystems were directly responsible for 25% of all diseases that could be classified as preventable (such as acute respiratory infections, malaria, diarrhea, hepatitis and occupational diseases). Water pollution occurs according to the specific sources of pollution from household drainage in many parts of Egypt, especially in rural villages. If water pollution is allowed to grow unchecked, it has the potential to cause major economic and health repercussions for the country. Among the most important research that can contribute to solving the problem of water purification, improvement of its quality and reuse even in agriculture instead of waste and disposal, for example, like many scientific methods applied in this regard. They include adsorption, precipitation, ion exchange, reverse osmosis, electrochemical treatments, membrane filtration, evaporation, flotation, oxidation processes and bioabsorption. Advanced technologies for wastewater treatment are more beneficial and effective. It includes membrane filtration, ion exchange, electrolysis, absorption, etc. Membrane filtration used for treatment of wastewater is: ultrafiltration, reverse osmosis, nanofiltration, and electrophoresis dialysis. The development of new and cost-effective nanomaterials for various environmental concerns and other applications has attracted great interest. Recent developments indicate that many problems involving water quality can be identified by using nanoparticles, nanofiltration, or other products resulting from the development of nanotechnology. Therefore, membranes can be used in wastewater treatment. Therefore, this work aims to reuse wastewater by filtered it by preparing membranes from cellulose acetate, which the cellulose was extracted from rice straw, which is available as agricultural residues from rice cultivation. The membranes were formed by cellulose which extracted from rice straw. Rice straw consists of 35% cellulose, 25% hemicellulose, 20% lignin and 17% ash (mainly 94% silica by weight). Magnetite nanoparticles have been extensively prepared for many technological, medical and industrial applications: such as magnetic nanoparticles. So is the imidazole zeolite ZIF-8. In particular, the prepared ZIF-8 imidazole nanoparticles and zeolite framework were used as filler for the porous membrane to apply these nanoparticles and ZIF-8 in various potential fields. Cellulose was extracted from rice straw, which used in the manufacture of membranes. The cellulose acetate membranes were manufactured by TIPS thermally induced phase separation which allows an exchange between the solvent and the nonsolvent to form pores. The cellulose acetate membrane was modified with various additives such as calcium carbonate, polyvinylpyrrolidone and polyethylene glycol with different weight% such as (4, 6, 8, 10 wt%) each material separately, and also magnetic nanoparticles and ZIF-8 imidazole zeolite were added as fillers to reduce pore size. The additives act as a pore filler, which reduces the size of the pores and will lead to an increase in the efficiency of the membranes in wastewater treatment, which was confirmed by SEM and AFM tests compared to the cellulose acetate membrane without any additives. The chemical composition was verified to demonstrate the extraction of cellulose, the formation of cellulose acetate, the preparation of magnetic nanoparticles and imidazole zeolite ZIF-8, and the synthesis of all types of films with different additives. Using the FTIR infrared test The thermal stability and magnetic component of all materials were studied by thermogravimetric analysis which proved to enhance thermal stability compared to cellulose acetate film without any additives. The factors affecting the efficiency of the membrane were studied. We study the pH, the effect of temperature, and the type and concentration of additives. Atomic flame absorption spectroscopy and ion chromatography were used to measure IONS ions before and after the filtration process, to evaluate the efficiency ratio of the prepared films. The efficiency of the modified membranes was evaluated in treating a sample of wastewater, and the results proved that modifying the cellulose acetate membranes with polyvinyl pyrrolidone at 10% wt gives the highest rate in water purification, and then adding a weight ratio of 1% of nanoparticles or zeolite imidazole ZIF 8- To the membranes modified with polyvinylpyrrolidone to raise its efficiency, which was confirmed by the SEM and AFM tests, compared to the cellulose acetate membrane without any additives At the end of the work it was determined that the best additive was polyvinylpyrrolidone at pH 7and 35oC. It can be seen that the order of the efficiency of polymers and magnetic nanoparticles on the membrane removal efficiency is MT- 24> MT-20> MT-28> MT-11> MT-7> MT-15> MT-16> MT-3> MT- 2 This can be explained by the fact that the additives increase the surface area of the membrane, which reduces the size of the pores and thus increases the efficiency of removal. |