The role of CQDs in lithium ion sieve to recovery Li + from neutral salt lake brine

Abstract

The demand for lithium and its compounds is increasing by years, but separating lithium ions from brines are challenging. A novel material of Peach gum Carbon Quantum dots (PG-CQDs) lithium ion sieve was prepared by using a simple precipitation method and heat treatment. The molecular formula of the adsorbent compound was H2.05Mn1.86C0.43O4 and the maximum adsorption capacity reached 34.6 mg/g, approximately twice that of the unmodified adsorbent, with a separation factor of 293.2–11434 in brine with a high Mg/Li ratio. Experimental and theoretical analyses indicated that he presence of Mn-O-C bonds in the adsorbent and that CQDs increase the pore structure of the lithium ion sieve and that the crystallisation of the original material changes, leading to an increase in BET surface area, proton number and adsorption capacity. The outstanding material can be massively used in lithium ions extraction in complex water system and carbon quantum dots doping Li+ sieve have potential application value for extracting lithium ions.