Synthesis of granulated Li1.33Mn1.67O4 via two antisolvent methods for lithium adsorption from gas-produced water

Gas-produced water is an accompanying wastewater in the natural gas extraction process, and it is a potential liquid lithium resource that contains a considerable amount of lithium. This study investigated the feasibility of using manganese-based ion sieves to adsorb and extract lithium from gas-produced water. And we focused on the applicability of two different granulation methods, extrusion and droplet, in gas-produced water systems. Two types of H1.33Mn1.67O4 particles were prepared by the extrusion method (EHMO) and the droplet method (DHMO). The porosity of DHMO was much higher than that of EHMO, and the adsorption performance of DHMO increased with the decrease of binder concentration. DHMO prepared with a binder concentration of 0.14 g<middle dot>ml(-1) exhibited the best adsorption performance in gas-produced water, and the Li+ adsorption capacity could reach 25.14 mg<middle dot>g(-1). In gas-produced water, the adsorption equilibrium of DHMO only took 9 h, and the adsorption process conformed to the Langmuir model and pseudo-second-order kinetic model. The pore diffusion model (PDM) could well describe its adsorption process. Besides, DHMO showed a great selectivity to Li+, and the selectivity order of DHMO in gas-produced water was Li+>Ba2+>> Mg2+, Ca2+, Sr2+>> Na+>> K+. After 20 cycles, the Li+ adsorption capacity was still higher than 17.30 mg<middle dot>g(-1), and the rate of manganese dissolution was less than 1%.