Advances on high temperature Pd-based membranes and membrane reactors for hydrogen purifcation and production

Membrane technology applied in the chemical and energy industry has the potential to overcome many drawbacks of conventional technologies such as the need of large volume plants and large CO2 emissions. Recently, it has been reported that this technology might become more competitive when operated at high temperatures. This is mostly associated with the required of heat integration at large scale. However, good membrane stability combined with high permeation rates and high perm-selectivities, has only been achieved at intermediate/low temperatures (< 500 °C). When operated at these lower temperatures in a fully integrated plant, there is often the need of electricity import, which strongly decreases the process efciency and renders the membrane-based technology less competitive compared to conventional technologies. To improve the competitiveness of membrane technology further developments are required, demanding in particular an improvement in the preparation methods, the use of new materials and/or the development of novel reactor confgurations. In this study, a comprehensive review on the latest advancements in membrane technology for H2 separation at high temperature is presented. Special attention is given to the membranes prepared and presented in the literature in the last years for high-temperature applications, as well as the different membrane reactor confgurations that have proposed, tested and evaluated for different reaction systems at elevated temperatures. Since concerns about the need of high temperatures in membrane technology are relatively new, this review is limited to the results reported in the literature during the last fve years.