## 3 Results
### Cs+ Adsorption Efficiency and Magnetized Zeolite Recovery Efficiency  
The Cs+ adsorption efficiencies and magnetized zeolite recovery efficiencies of the magnetized zeolites with different particle sizes were evaluated with 24 h cascade adsorption experiments using simulated Cs-contaminated soil, followed by magnetic separation and recovery for 1 min. The ratio of magnetized zeolite and soil (by weight) was kept at 0.5, and 3.33 g of magnetized zeolite was mixed with 6.67 g of wet contaminated soil (total weight of 10 g), while the Cs+ concentration in the contaminated soil was kept at 1 wt% with a 20 wt% moisture content in the soil, as shown in Table S2. The Cs+ concentration in the treated soil was characterized by XRF, and the adsorption efficiency was determined from the Cs+ remaining in the soil divided by the initial Cs+ concentration. The magnetized zeolite recovery ratio was determined by weighing the zeolite recycled in the magnetic separation cylinder, as shown in Figure 11 and Supplemental Table S2. The results indicate that the magnetized zeolite exhibited efficient Cs+ adsorption and Cs+ removal rates up to 99.92% for the magnetized zeolite with 60-80 mesh particle sizes; this was inconsistent with the theoretical adsorption kinetics, which should be higher after particle subdivision. In theory, a fine-grained zeolite was sufficiently reactive in Cs+ adsorption, which was not the phenomenon operating herein [34]. The reason for this can be attributed to the intrinsic weakness of the operation process, which affects the separation of fine-particle zeolite. A small proportion of the fine-grained zeolite was blocked by the soil particles during the magnetic rotating vibration separation process in the magnetic cylinder, so that was not adsorbed by the inner wall of the magnetic cylinder and was carried into the product during the discharge process. The adsorption capacity of the magnetic zeolite with medium particle sizes was higher due to the better adsorption exchange reaction and breakthrough steric hindrance. The particle sizes of magnetized zeolite affected the removal rate of Cs+ in the soil and the waste reduction ratio in the above analysis. For actual polluted soil, the treatment would be improved by controlling the particle size range of the magnetized zeolite. The preparation process can be used to control the particle sizes appropriately. Based on the different particle sizes of the contaminated soil and the zeolite, the magnetized zeolite could be recovered and recycled through magnetic treatment with a recovery ratio as high as 96%, as shown in Table S2. Generally, the magnetized zeolite was more efficiently recovered with coarse zeolite and finely contaminated soil, which should guide the design of the magnetized zeolite and the industrial treatment process [35]. The following table shows that the specific surface area of the coarse-grained zeolite was small, most of the pores with Cs+ adsorption and exchange capacity were located inside the particles, and the diffusion and exchange of Cs+ into the interior and the release of Na+ and K+ all required long reaction times. Therefore, the Cs adsorption and adsorbent recovery rates of the magnetized zeolite were summarized with the schematic in Figure 11d: the initial contact of the magnetized zeolite particles with the Cs-contaminated soil triggered adsorption, which was accelerated by agitation, followed by the adsorption of Cs in the pores of the zeolites. Separation and recovery of the magnetized zeolite were accomplished with an external magnetic field, for example, the magnetic cylinder designed herein.