Arsenic.sub.0.8] alloy porous microfibers

The magnetic, nanocrystalline [Fe.sub.0.2][([Co.sub.20][Ni.sub.80]).sub.0.8] alloy porous microfibers were prepared by the citrate gel thermal decomposition and reduction process. The morphology, chemical composition, microstructure, and magnetic properties of the microfibers were investigated by X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray, Brunauere-Emmette-Teller, and vibration sample magnetometer. The as-prepared magnetic, nanocrystalline [Fe.sub.0.2][([Co.sub.20][Ni.sub.80]).sub.0.8] porous microfibers consisting of about 48 µm grains are characterized by diameters of 1-4 pm, specific surface area of 17.73 [m.sup.2]/g, and specific magnetization of 196.7 A[m.sup.2]/kg. The arsenic(V) absorption on these magnetic [Fe.sub.0.2][([Co.sub.20][Ni.sub.80]).sub.0.8] porous microfibers at room temperature was determined by the ICP-AES measurement of arsenic(V) in aqueous solution. The results show that the pseudo-first-order kinetic model is consistent with the arsenic(V) adsorption process and a good correlation coefficient ([R.sup.2] = 0.9862). By comparing among the Langmuir, Freundlich, Temkin, and Redlich-Peterson models for adsorption isotherms of arsenic(V) onto the magnetic v porous microfibers at room temperature, the Freundlich model and RedlichPeterson model can be used to evaluate the arsenic(V) adsorption isotherm at room temperature. The arsenic(V) equilibrium absorbance of the magnetic [Fe.sub.0.2][([Co.sub.20][Ni.sub.80]).sub.0.8] porous microfibers is up to 1.9 mg/g when the initial arsenic(V) concentration is 1.0 mg/L in aqueous solution. Keywords Arsenic adsorption * [Fe.sub.0.2][([Co.sub.20][Ni.sub.80]).sub.0.8] alloy * Porous microfibers * Citrate gel * Adsorption kinetics * Adsorption isotherms