In the context of hydrometallurgical processes dedicated to the recovery of metals, the leaching step consists of dissolving solid particles (ores, waste to be recycled) in an aqueous phase. With the aim of improving yields, a wiser use of resources and reducing effluents, the BIOMECALIX project aims to study the interest and feasibility of an innovative, competitive and eco-efficient leaching process. This hybrid process combines the advantages of bioleaching (moderate temperature and acidity, in situ production of the oxidizing reagent by microorganisms) and attrition leaching (in situ grinding, abrasion of passivation layers by agitated grinding media). The case of application is chalcopyrite, but the general framework is for leaching processes involving a redox reaction. Such a coupling raises several scientific issues: (i) Does the lifting of the two major kinetic barriers (redox reaction thanks to bacteria and passivation thanks to attrition) make it possible to reach the yields predicted by thermodynamics? (ii) What is the impact of hydrodynamic and mechanical stresses on microorganisms? (iii) What is the limiting step: bacterial growth or activity, gas-liquid transfer (oxygen required for bacterial activity), dissolution reactions, attrition of passivation layers? The proposed methodology combines experimental work in different types of reactors and modeling work. The project gathers a consortium of experts in process engineering, reactor engineering, thermodynamics, modeling, microbiology and hydrometallurgy, at the Chemical Engineering Laboratory (LGC) and at the Geological and Mining Research Bureau (BRGM). It is planned to recruit a doctoral student, a postdoctoral fellow and six trainees during the 42 months of the project. The work program has four technical tasks. The first two tasks concern the adaptation of the uncoupled processes (currently developed by each of the partners) to the conditions of a hybrid reactor. Thus, the attrition leaching will be studied under biocompatible conditions (moderate pH, T between 40 and 55 ° C, oxygen supply) by the LGC, while the BRGM will evaluate the impact of the conditions inherent to the attrition process (high solid/liquid ratio, presence of grinding media, hydrodynamic stresses) on microorganisms. A third task will be to establish the proof of concept of the hybrid process, based on a reasoned selection of operating parameters, and by conducting experimental campaigns in a reactor developed for the project. In parallel, a fourth task will focus on proposing a leaching model integrating thermodynamic equilibria, kinetic laws related to different phenomena, and shear stresses. This model will support the establishment of the balance sheets of the process, and the development of a simulation tool of the hybrid process. This tool will be used for a techno-economic assessment and the establishment of a quantitative comparison (energy and environmental) of the hybrid process compared to existing processes for the treatment of chalcopyrite, in aqueous and pyrometallurgical ways.