THEME 2 (Team EIP)*

?The electrochemical reactors have been used for more than a century in much industry. The metal production such as aluminum production or gas production such as chlorine production are the main industries that they use electrochemical reactors. Moreover electrochemical synthesis and pollution treatment using electrochemical device are led by numerous company. Nevertheless electrochemical reactions are heterogeneous processes and there are similar to catalyst reactions. These singular surface reactions involve mass transport losses which are associated with the transport of charged and uncharged species in the electrolyte and in some cases: gas phases. These limitations could have severed effects on the operation of electrochemical cell. In the same way heat balance are strongly linked to electrochemical performance.

Unfortunately, corrosion is a natural process, which converts a refined metal to a more stable form, such as its oxide or hydroxide. This phenomenon depends on complex interaction between materials and surrounding atmosphere, temperature, etc. The annual cost of corrosion worldwide is over 3% of the world’s GDP. Prevent the corrosion is a great world challenge.
Scientific research that takes place on industrial items (devices: battery; elements: wire; barring, etc.) is widely investigated in EIP workgroup. In electrochemical engineering sub-work group, the studies are devoted to model and optimize these devices. In our group (IEP) the multidisciplinary approach (Chemical engineering approach) is essential to solve the complex problems of electrochemical reactors and of material corrosion.
Figure 1: Diagram of research actions on electrochemical devices and the developed topics

Nowadays, the use of renewable energy source is inherently variable, on both short-term diurnal cycles and longer-term seasonal cycles. Electrochemical devices have successfully proved the energy storage possibility: secondary batteries, electrolyzer, fuel cell, etc. In point of view of fully sustainable technology, bio-electrochemical system that drives a current by using bacteria could be used to feed an energy device, including coupling cells to wastewater treatment plants. Recently a number of companies have emerged to commercialize these bioelectrochemical reactors. Therefore, studies of bioelectrochemical reactors require some new specific tools.

In this scientific context and in this societal context, the EIP research group provides original tools and specific methods applied to industrial devices.

General contacts : team leader : Dr. Jonathan Deseure. Head of the group: Pr. Marian Chatenet

Microbial bioelectrochemical systems (contact: Gérard Merlin)

Microbial bioelectrochemical systems (BESs) are considered to be a seminal sustainable technology conception. For example, BESs are emerging as a new technology platform for removal and recovery of metal ions from metallurgical wastes, process streams and wastewaters. Recently we develop mathematical approach to calculate substrates concentrations distribution, overpotentials and pH gradients within the biofilm thickness which involve spatial distribution of microbial species. In addition we develop novel carbon foam materials from bio-sourced materials with appropriate properties in order to improve exo-electroactivity of biofilm.

(Anti) corrosion (contact: Virginie Roche)

The (anti) corrosion research concerning bio compatible metallic material is a great challenge for human health. Since 2010, biocompatible metallic glasses based on Ti, Fe or Mg are investigated, because of their unique mechanical properties, to study biodegradation and bioactivity. The corrosion resistance of nanocrystalline (partially crystallized) coatings are investigated. Thanks to, the “Local Electrochemical Impedance Spectroscopy (LEIS)” device, the local characterization of heterogeneous reactivity along the surface (defects, porosity …) is made possible.

Modelling and Electrochemical engineering (contact: Jonathan Deseure)

In order to improve materials lifetime and electrochemical performances,coupling the modelling and the electrochemical technics - (e.g electroanalytical technics, conductimetry, impedance meter, sensors etc.) is a powerful approach to investigated chemical and physical processes: chemical step, reactions, mass balance, momentum balance, heat balance and charge balance. A particular approach is essential for each device (battery, electrolyzer, etc.). Li-batteries have needed to be smartly led during charging to increase durability; fuel cell are intrinsically controlled by multiphysic processes, thus the detection of defaults during operation is a great challenge; intensive production is required for industrial use of electrolyzers, thus a new conception strategy of these devices is investigated. In the thinking of EIP workgroup, a relevant model of electrochemistry employs a minimum amount of parameters to forecast the behavior of electrochemical devices. Exact fitting are not the aim of work group investigations. Thanks to an accuracy method it is possible to identify the physical process that control the device and act to this in order to improve cell performances.

Update - 24/10/2019