The concentration of hydriodic and sulfuric acid aqueous solutions by membrane distillation (MD) was experimentally investigated. Two commercial hydrophobic membranes, with two different recirculation batch configurations, were tested: direct contact membrane distillation (DCMD) with a polypropylene (PP) capillary membrane, and air-gap membrane distillation (AGMD) with polytetrafluoroethylene (PTFE) flat-sheet membrane. Feed temperatures were 58 °C for DCMD and 80 °C for AGMD, with cooling water at 15 °C and 1 atm operating pressure in both cases. H2SO4concentration in the feed solution increased from 1.1 up to 7.0 mol/L with the DCMD and from 0.9 up to 10.1 mol/L with the AGMD. HI concentration increased from 0.3 up to 7.0 mol/L with the DCMD and from 0.3 up to 8.0 mol/L with the AGMD. The latter value is higher than the azeotropic concentration of the HI / H2O (7.57 mol/L) mixture and, hence, HI further separation from water can be easily achieved with conventional distillation units. Durability of PTFE membrane in acid solutions was assessed too. © 2007 International Association for Hydrogen Energy.
All Science Journal Classification (ASJC) codes
- Fuel Technology
- Renewable Energy, Sustainability and the Environment
Caputo, G., Felici, C., Tarquini, P., Giaconia, A., & Sau, S. (2007). Membrane distillation of HI / H2 O and H2 SO4 / H2 O mixtures for the sulfur-iodine thermochemical process. International Journal of Hydrogen Energy, 32(18), 4736 - 4743. https://doi.org/10.1016/j.ijhydene.2007.07.011