Preparation method of rare earth-doped hydrated manganese oxide adsorbent

The invention discloses a preparation method of a rare earth-doped hydrated manganese oxide adsorbent. The preparation method comprises the following steps: firstly preparing a mixed liquid I from a MnSO4.H2O solution with the molar concentration of 2%-5% and a NaCl solution with the molar concentration of 2%-10%, and adding a 0.1%-0.5% KMnO4 solution into the mixed liquid I so as to prepare a hydrated manganese dioxide seed crystal mixed liquid; carrying out rare earth-doped crystal particle amplification on the hydrated manganese dioxide seed crystal mixed liquid; carrying out precipitate size grading on a rare earth-doped hydrated manganese oxide mixed liquid, and carrying out filter pressing on precipitates with particle sizes larger than 10 microns so as to obtain adsorbent filter cake; drying the adsorbent filter cake at 50-75 DEG C for 1.5-3 hours until no obvious moisture is left on the surface of the adsorbent filter cake, thereby obtaining the finished adsorbent. The adsorbent is high in adsorption