fabrication, characterization, regeneration and application of nanomagnetic fe3o4@fish scale as a bio-adsorbent for removal of methylene blue

The methylene blue (mb) adsorption from aqueous solution was investigated through fe3o4 nanoparticles loaded on fish scale (fs) from fishery biomass. the presence of collagen fibers, apatite crystals and nanomagnetite particles in the structure of nano-magnetic fish scale (mfs) was observed in ftir, ema and xrd results. from nitrogen physisorption studies, the fs and mfs specific surface areas were estimated at 0.65 and 4.86 m2/g, respectively. the negative values of δg0 and δh0 confirmed that the adsorption was a spontaneous and exothermic process, respectively. the mb adsorption onto mfs was a physisorption controlled process. the sips equation estimated the best fit to the data compared with other isotherm equations. the langmuir and sips maximum adsorption capacities (qmax) were 68.72 and 60.87 mg/g, respectively. mb removal by mfs followed the model of pseudo-second order rate kinetics. the reusability potential of the mfs was studied, and results showed an efficiency of 59.63%.