scholarly journals The Effect of the NaCl Bulk Concentration on the Resistance of Ion Exchange Membranes—Measuring and Modeling

Energies ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1946 ◽  
Author(s):  
Joost Veerman
Keyword(s):  
Ion Exchange ◽  
Membrane Resistance ◽  
Ion Exchange Membranes ◽  
High Concentration ◽  
Reverse Electrodialysis ◽  
Low Concentrations ◽  
Nacl Concentration ◽  
Data Points ◽  
Membrane Contact ◽  
Almost All

Ion exchange membranes are used in different fields of energy and separation technology such as electrodialysis, reverse electrodialysis, and fuel cells. Important aspects are permselectivity, resistance, and water transport. In this paper, we focus on the effect of the bulk NaCl concentration on the membrane resistance. Data from 36 publications containing 145 datasets using 6 different methods for measuring membrane resistance were compared. This study showed that the membrane resistance is dependent on the method of measuring. Two probable causes are identified: the application of reference electrodes and the presence of direct electrode–membrane contact. In addition, three physical and three phenomenological membrane models were tested by fitting these to the datasets. First, fits in the resistance domain were compared with fits in the conductivity domain. Resistance fits are sensitive to fluctuations in low concentrations, whereas fits in the conductivity domain are subject to nonlinear responses at high concentration. Resistance fits resulted in higher coefficients of determination (R2). Then, the six models were compared. The 1-thread model with two fit parameters was in almost all cases a good start. More improvements were difficult to test due to the restricted number of data points in most of the used publications, although this study shows that the so-called Gierke model (with 4 parameters) fits better than the 3-thread model. Phenomenological models were also tested, but they did not lead to much better fits.

scholarly journals The Influence of Concentration and Temperature on the Membrane Resistance of Ion Exchange Membranes and the Levelised Cost of Hydrogen from Reverse Electrodialysis with Ammonium Bicarbonate

Membranes ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 135
Author(s):  
Yash Dharmendra Raka ◽  
Robert Bock ◽  
Håvard Karoliussen ◽  
Øivind Wilhelmsen ◽  
Odne Stokke Burheim
Keyword(s):  
Ion Exchange ◽  
Waste Heat ◽  
Ammonium Bicarbonate ◽  
Operating Efficiency ◽  
Membrane Thickness ◽  
Ion Exchange Membranes ◽  
Reverse Electrodialysis ◽  
Ohmic Resistance ◽  
Production Of Hydrogen ◽  
The Impact

The ohmic resistances of the anion and cation ion-exchange membranes (IEMs) that constitute a reverse electrodialysis system (RED) are of crucial importance for its performance. In this work, we study the influence of concentration (0.1 M, 0.5 M, 1 M and 2 M) of ammonium bicarbonate solutions on the ohmic resistances of ten commercial IEMs. We also studied the ohmic resistance at elevated temperature 313 K. Measurements have been performed with a direct two-electrode electrochemical impedance spectroscopy (EIS) method. As the ohmic resistance of the IEMs depends linearly on the membrane thickness, we measured the impedance for three different layered thicknesses, and the results were normalised. To gauge the role of the membrane resistances in the use of RED for production of hydrogen by use of waste heat, we used a thermodynamic and an economic model to study the impact of the ohmic resistance of the IEMs on hydrogen production rate, waste heat required, thermochemical conversion efficiency and the levelised cost of hydrogen. The highest performance was achieved with a stack made of FAS30 and CSO Type IEMs, producing hydrogen at 8.48× 10−7 kg mmem−2s−1 with a waste heat requirement of 344 kWh kg−1 hydrogen. This yielded an operating efficiency of 9.7% and a levelised cost of 7.80 € kgH2−1.

scholarly journals The permselectivity and water transference number of ion exchange membranes in reverse electrodialysis

2017 ◽  
Vol 523 ◽  
pp. 402-408 ◽  
Author(s):  
A. Zlotorowicz ◽  
R.V. Strand ◽  
O.S. Burheim ◽  
Ø. Wilhelmsen ◽  
S. Kjelstrup
Keyword(s):  
Ion Exchange ◽  
Transference Number ◽  
Ion Exchange Membranes ◽  
Reverse Electrodialysis

scholarly journals REMOVED: Ion exchange Membranes for Reverse Electrodialysis

2012 ◽  
Vol 44 ◽  
pp. 1328-1330
Author(s):  
E. Guler ◽  
K. Nijmeijer ◽  
M. Saakes
Keyword(s):  
Ion Exchange ◽  
Ion Exchange Membranes ◽  
Reverse Electrodialysis
Sign in / Sign up

Export Citation Format

Share Document