Ceramics for environmental applications: filters, membranes, adsorbents and catalysts

Growing environmental pressures, such as the massive pollution of air and water resources and the accelerating depletion of fossil fuel reserves, have led to the concept of sustainable development and associated strategies such as the treatment of liquid and gaseous effluents, on-site water purification and recycling, and the use and purification of bioresources, the lightening of transport vehicles, the use of new energy carriers, such as dihydrogen, or more generally the intensification of processes (associated with the notion of "atom economy", an indicator measuring the efficiency of a process and equal to the ratio, weighted by the appropriate stoichiometric coefficients, of the molar mass of the product to be synthesized by the sum of the molar masses of the reagents). National and international environmental regulations are becoming increasingly stringent, and are therefore an important lever for the introduction of new industrial processes, as well as for the expansion of research and development efforts into clean processes and the remediation of polluted environments.

Thanks to specific properties such as refractoriness, chemical stability and mechanical resistance to compression, as well as the wide range of accessible microstructures, porosities and geometries, ceramics are an essential class of materials for many industrial processes currently in use or under development, with the aim of protecting the environment. This article illustrates this point by looking at applications in filtration, heterogeneous catalysis, adsorption and coupled operations, such as in catalytic membrane reactors, based on the multifunctionality of the materials or systems involved.