5EA set to skyrocket, page-14

There is a few different ways as I've heard about from when I was more active in the lithium space.

High pressure and special membranes plus voltage from our waste brine which I believe might be inline with what the authors of this article used.
Direct numerical simulation of continuous lithium extraction fromhigh Mg2+/Li+ ratio brines using microfluidic channels with ionconcentration polarization

Other proprietary direct lithium processes using various tricks.

I think another definition of direct extraction could be an active heating step rather than the traditional evaporation pond and then standard lithium carbonate processing.

Possibly other ways to go about it if your end customers prefer lithium hydroxide depending on their industrial processes.

High-pressure and special membranes seems like a potentially cost-effective option.