IIT Madras professor wants to produce hydrogen by reacting sea water with aluminium

Prof Satyanarayanan Chakravarthy of the Indian Institute of Technology, Madras, has designed a process for producing hydrogen by reacting sea water with aluminium. 

As sea water (any water) reacts with aluminium (any metal), the oxygen joins with the metal to form oxide (alumina), liberating hydrogen. There are two problems, though. First, the oxygen forms an oxide layer, preventing further reactions. Second, aluminium (any metal) costs money, making the process economically unviable.

Chakravarthy has tackled the two problems this way. His design uses aluminium nano particles to counter the first problem. As for the second, the process recovers aluminium from alumina. 

                                                        Dr Satya Chakravarthy

Now, recovery of aluminium from alumina is an energy-consuming process, for two reasons. It requires energy to operate and the electrolysers use electrodes that are consumed away in the process.

Once again, Chakravarthy's system has answers. As for energy, there is some within the system. If you react the liberated the hydrogen with the atmospheric carbon dioxide with an aim to make methanol, that reaction produces heat which can be tapped. And for electrodes, Chakravarthy has come up with non-consumable electrodes--titanium diboride cathode, nickel ferrite anode, immersed in an electrolytic bath of molten cryolite.

Chakravarthy says the process is both technically and economically feasible. It is being worked into a pilot through a start-up that Chakravarthy mentors, called X2Fuels Energy. The start-up is looking for funding for the pilot and beyond.

The following visuals explain the process better.

"Experimental investigations of novel catalytic reactors, pointing out their greater heat transfer properties, which is mainly appealing for the design of small-scale methanol synthesis processes have been established. Significant catalytic research has been conducted in IIT Madras, which has provided a fundamental understanding of the different process conditions and the behaviuor of different catalysts," says Chakravarthy. "Our next step is towards a pilot scale continuous plant, with systematic scale-up road-map."