Techno-Economic Feasibility Analysis for Minor Elements Valorization from Desalination Concentrates

Water and raw materials scarcity are challenges that our society faces today. Seawater desalination has become essential for the supply of fresh water mainly due to the development of seawater reverse osmosis (SWRO). The depletion of conventional extractable resources and the increase in the use of certain metals encourage the development of nonconventional sources. Attending to the increasing global desalination capacity, the extraction of minor components concentrated in the SWRO brines can become a valuable source of target compounds. This work evaluates the potential interest for extraction of minor components in SWRO concentrates. The target metals are selected attending to the relevance of their applications, the market trend, the depletion of conventional resources and the state of the art of the extraction technologies. The main challenges to be overcome are highlighted. Results are summarized in a ranking where the inputs for research are categorized in three levels resulting in a useful decision tool. Cs, In and Rb are pointed as promising metals to upgrade their extraction technologies from SWRO concentrates. Significant research contributions are needed in order to develop viable strategies for the recovery of valuable materials from SWRO brines.