Ion Exchange Membranes for Electrodialysis: A Comprehensive Review of Recent Advances

Abstract

Electrodialysis related processes are effectively applied in desalination of sea and brackish water, waste water treatment, chemical process industry, and food and pharmaceutical industry. In this process, fundamental component is the ion exchange membrane (IEM), which allows the selective transport of ions. The evolvement of an IEM not only makes the process cleaner and energy-efficient but also recovers useful effluents that are now going to wastes. However ion-exchange membranes with better selectivity, less electrical resistance, good chemical, mechanical and thermal stability are appropriate for these processes. For the development of new IEMs, a lot of tactics have been applied in the last two decades. The intention of this paper is to briefly review synthetic aspects in the development of new ionexchange membranes and their applications for electrodialysis related processes.

Biomolecules and Electrochemical Tools in Chronic Non-Communicable Disease Surveillance: A Systematic Review

“…Consequently, different methodologies for signal transportation into transducer surface had to be developed and following the signal mode or electron transfer methods used for biochemical reaction measurements. Therefore, amperometric enzyme-based biosensors have been developed over the so-called three “generations” ( Figure 4 ) [ 53 ].…”

“…Each type of coating material used on the electrode surface (carbon support, polymer, nanomaterials, enzymes, etc.) has an impact on the impedance plots and reflects the current flow capacitances and impedances [ 53 ].…”

“…For the enzymes immobilized at the electrode, such detriments result mainly from protein denaturation and consequent deactivation, which ultimately reduces the useful life of the sensor when adsorbed at the electrode surfaces [ 53 ]. The adsorption of denatured proteins leads to the bioactivity loss.…”

“…Also during the immobilization process itself, there is a high probability that enzyme denatures, due random distribution and/or incorrect dispersal of proteins onto electrode’ surface, and causing a misalignment of the proteins’ redox centre concerning the electrode surface, which may block entirely or partially the active site of the enzyme [ 53 ].…”

“…In general, there are two main failures in enzymatic/mediated biosensing, concerning the decline in its catalytic activity [ 53 ]: When the conductive material detaches electrode surface When the electrode experiences biofouling or passivation. …”