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Background and Objective: In recent years, chitosan and Moringa oleifera Coagulant Protein a natural coagulant were used in order to reduce the problems occure from chemical coagulants. This investigation was done to determine effectiveness of Moringa Oleifera Coagulant Protein and Chitosan as natural coagulant aids in removal of colloidal particles and bacteria from turbid waters. Materials and Methods: In this interventional- quasi experimental study, the experiments were run by using synthetic water having low(10-20NTU), medium(100-120NTU) and high (200-220NTU) initial turbidities. In order to determine optimum pH and dosage of coagulant and coagulant aids, a conventional jar test apparatus was employed. Turbidity reading were carried out using a Hach model 2100P Turbidimeter. The samples were taken from the top four inch of the suspension for turbidity and bacteria removal measurement. Results: Optimum dose of alum for waters with three different initial turbidities were 20, 40, and 20 mg/l, respectively. Optimum pH was between 7-7.5. Moringa oleifera Coagulant Protein and chitosan were reduced the required dosage of alum from 12.5% to 62.5% and from 50% to 87.5%, respectively, in different turbidities and residual aluminum was reduced to standard limit (0.2mg/l). The bacteria removal efficiency were from 90% to 99.9999%. It was found when samples were stored during 24 hours regrowth of E.coli was not observed. Conclusion: This study showed that natural coagulant aids can reduce the turbidity to below 5NTU without filtration in optimum condition.

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Background and Objective: Raw water is one of the main sources of water supply in some communities. Filteration of surface water resources is a challenging point in the rainy seasons due to the highly turbidity. This study was done to evaluate the removal of turbidity in raw water using chitosan in electrocoagulation process using aluminum electrodes. Methods: In this the descriptive –analytical study, a Plexiglas electrocoagulation reactor in a lab scale to an approximate volume of 6 liter which was equipped with four aluminum electrodes having dimension of 200×20×2 mm was proposed. The effects of operating parameters including pH (5 to 9), applied voltage (10 to 30 V), the initial turbidity (100-600 NTU), initial chitosan concentration (0.5-2 mg/L) and contact time (5 to 30 min) were evaluated. Results: Turbidity removal efficiency was over 100% (pH=7, applied voltage=30 V and initial turbidity concentration of 100NTU) in the application of electrocoagulation with chitosan but in the application of electrocoagulation without chitosan removed 87% of turbidity in the same condition. Conclusion: Chitosan as coagulant aid in low amount can increase turbidity removal efficiency rather than application of electrocoagulation alone.

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Background and Objective: Iron oxide nanoparticles have wide applications such as MRI contrast agent and drug delivery. Nevertheless, their effects on human health have not been fully investigated yet. After cellulose, chitin is one of the most abundant organic materials in nature which is widely used in food industry, cosmetics, agriculture, medicine and the environment. This study was done to evaluate the effect of iron oxide nanoparticles coated with chitosan on renal functional indeces in rat.

Methods: In this experimental study, 60 adult female Wistar rats were allocated into 10 equal groups. Concentrations of 50, 100 and 150 mg/kg/bw from chitosan, iron oxide nanoparticles and chitosan coated nanoparticles were intraperitoneally injected into 9 groups and animals in control group were received normal saline. Blood samples were collected directly from the rat heart in the days 15 and 30 post after injection and renal functional indeces including urea, creatinine, uric acid, sodium, potassium and total protein were measured.

Results: There were no significant differences in the level of urea, creatinine, uric acid, sodium, potassium and total protein in the groups whom received chitosan-coated iron oxide nanoparticles compared to control. There was no mortality during the study time.

Conclusion: Short-term using of iron oxide nanoparticles coated with chitosan does not create any toxicity in the rat kidney.