Comparison of the performance of plant nano-hydrogels as bio-filters for nitrite uptake from effluent of fish farms

The aim of this study was to evaluate the performance of plant nano-gels as a new adsorbent and to remove nitrite at low cost. At first, plant nano-gels (nano bagasse, chitosan-functionalized nano-fiber and lignocellulose nano-fiber) were prepared by mechanical and top-down mechanism. Batch system medium was designed to measure the adsorbent optimum. Then isotherm and synthetic were calculated to estimate absorption coefficients. The optimum amount of adsorbent weight for each nano gel was: 0.1 g for nano bagasse and lignocellulose fiber; 0.3 g for modified nano fiber; 4 for nano bagasse and lignocellulose fiber and 5 for modified nano fibril; also initial concentration and the time for all adsorbents was 25 mg /l and 60 min. According to the equilibrium equations, the most consistent were considered with Langmuir, Freundlich and Temkin models. Results showed that the highest nitrite removal efficiency was related to functionalized nano-fiber with 93.1%; for nano-bagasse it was 65.51% and for lignocellulose nano-fiber was 68.96%. Eventually, the plant nano-gels can be used as bio-filters in the effluent system of fish farm.