![](bg5.png)
Figure 7: Results of five consecutive adsorption-desorption
for the reuse of microspheres for Pb (II) adsorption.
4 CONCLUSION
In this work, PMs and PAMs were successfully
fabricated through crosslinking with calcium ions.
The maximum adsorption capacity for Pb (II) of
PAMs was about 2.6 times of PMs which implied that
the adsorption ability of PAMs greatly increased.
And the selective adsorption capacity for Pb (II) of
PAMs was better than that of PMs. Moreover, the
result of regeneration experiments showed that the
removal efficiency for Pb (II) of PAMs was more than
54% after five adsorption-desorption cycles in a
binary ion mixture system. All the results above
implied that the newly-prepared PAMs might be the
promising adsorbent for Pb (II) in aqueous solutions.
ACKNOWLEDGEMENTS
This work was supported by Scientific Research
Foundation for Returned Scholars (Ministry of
Education of China, 201503), Opening Foundation of
Key Laboratory of Resource Biology and
Biotechnology in Western China (Northwest
University, Ministry of Education),Natural Science
Basic Research Plan in Shaanxi Province of China
(2017JM2016) and National Natural Science
Foundation of China (81673115).
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