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Mining resources have played a leading role in the development of humanity, and the demand for these raw materials is expected to increase in the foreseeable future. In addition, new technologies also require the extraction of new critical materials. These trends pose various challenges as there is a limited supply of natural resources, and standard mining and mineral processing practices are associated with significant environmental impacts, such as waste generation, energy and water consumption, and CO 2 emissions. The circular economy (CE) has recently gained attention as a model to address such a complex scenario. This work analyzes the current efforts towards the application of CE in mineral processing. Although advances have been made, this review shows that the most significant material flows and environmental impacts occur near the production sites, which currently limits the closure of loops. Besides, mining industries are conservative regarding the adoption of new technologies or processing strategies, which is another hindrance to the implementation of the CE. Thus, and with few exceptions, while some sectors are already facing advanced stages of CE (namely, CE 3.0), the mineral processing field struggles to advance from the basic CE requirements (i.e, CE 1.0 to CE 2.0).

Due to the progressive fall of the ore grades and the increasingly refractory composition of minerals, concentrating plants have increased which has led to an increase in the generation of tailings. Tailings, especially those obtained in the past, have remaining copper and other valuable species in quantities that can potentially be recovered, such as gold, silver, vanadium, and rare earth elements which transforms this abundant waste into a potential source of precious or strategic metals for secondary mining. One of the techniques of solid–liquid separation that processes solutions with low concentrations of metals corresponds to adsorption, and more recently biosorption, which is based on the use of biological matrices that do not constitute an environmental liability after application. Biosorption occurs as a consequence of the wide variety of active functional groups present in different types of biomass. Bacterial, fungal, plant, and algal biomasses have been described as biosorbents, mainly for the treatment of diluted and simple solutions. This work aims to recover copper from leached tailings using biomass of the red algae Gracilaria chilensis as a biosorbent. The tailing samples were taken from an abandoned deposit, in the north of Chile, and after an acid leaching copper was biosorbed, kinetics of adsorption and the equilibrium isotherms were studied, applying the Freundlich and Langmuir models. Operational parameters such as adsorbent dose, pH, and initial metal concentration were studied.

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