Fabrication of polyacrylonitrile-Li1.6Mn1.6O4 composite nanofiber flat-sheet membranes via electrospinning method as effective adsorbents for Li+ recovery from salt-lake brine

In this paper, polyacrylonitrile (PAN) as the binder and Li1.6Mn1.6O4 as the powder were used to prepare the composite nanofiber flat-sheet membrane-type adsorbent (ESNM-H) via the electrospinning method. The influence factor on membrane adsorption capacity for Li+ were investigated, such as the concentration of PAN, precursor content, and membrane thickness. When the content of PAN and Li(1.6)Mn(1.6)O(4 )were 10 wt% and 18 wt %, respectively, the equilibrium adsorption capacity for Li+ on ESNM-H with the thickness of 164 +/- 4 mu m was 1328 mg/m(2), and the actual adsorption capacity of powder H1.6Mn1.6O4 incorporated in the nanofiber membrane remained 92% of the unsupported powder. In the artificial salt-lake brine, the adsorption selectivity of ESNM-H for Li+ was higher to other interfering ions (Na+, Ca2+, K+ and Mg2+). After eight cycles, the adsorption capacity of ESNM-H decreased by 8%. The ESNM-H exhibited the better long-term stability. The ESNM-H packed column was enriched with Li+ from 100 mg/L to 726 mg/L after ten consecutive dynamic adsorption-desorption cycles. The overall results show that the composite nanofiber flat-sheet membrane-type adsorbent fabricated via the electrospinning method has potential applications and recyclability in adsorbing Li(+ )from salt-lake brine.

Automated summary

The ESNM-H prepared by electrospinning method shows high adsorption capacity and selectivity for Li+, good long-term stability, and potential applications for adsorption of Li(+) from salt-lake brine with recyclability.