Performance Evaluation of Magnetic Nanoparticles Coated with Chitosan as a Cationic Polymer in Turbidity Removal from Aqueous Solution

Water turbidity is caused by some particles, organic compounds and microorganisms. This study aimed to evaluate the performance of magnetic nanoparticles coated with chitosan as a cationic polymer in turbidity removal from aqueous solution.
In this empirical study, the chemical co-precipitation technique was used to synthesize the magnetic nanoparticles coated by chitosan polymer. The effect of magnetite nanoparticles doses (1, 2, 3 and 4 g/l), pH(in the range of 4, 6, 7 and 9), settling time (5, 10, 20, 30, 40, 50 and 60 min), external magnetic field strength(in the range of 0, 0.25, 0.5 and 0.7 Tesla) and initial various turbidity values (250, 500, 750 and 1000 NTU) were studied.
The study results showed that increasing the dose of nanoparticles, settling time, the external magnetic field, and the acidic conditions in the pH range of 5-6 were considered as the agents of increasing turbidity removal performance by chitosan-coated magnetic nanoparticles. Using the studied nanoparticles in the optimal conditions, the water turbidity decreased up to 99.5%.
As the study findings revealed chitosan-coated magnetic nanoparticles showed a good performance in turbidity removal from aqueous solutions. Using the external magnetic field could significantly reduce the settling time of magnetic flocs. As a result, simultaneous use of the studied magnetic nanoparticles with the external magnetic field can significantly reduce the turbidity of high turbid waters.