Page 10 - Penn State Civil and Environmental Engineering 2021 Annual Report

FACULTY RESEARCH FACULTY RESEARCH Le Shi postdoctoral researcher in in in environmental engineering and and first author of of of the paper and and Bruce Logan Kappe Professor Professor of of of of Environmental Engineering and Evan Pugh University Professor Professor examine their newly designed sea water electrolyzer IMAGE: Tyler Henderson
10
Generating
renewable
hydrogen fuel
from the sea Researchers use membranes that remove salt from water to to help “split” sea water into fuel
By Tim Schley
Bruce Logan CEE NEWSLETTER • VOLUME 37 2021
The power of the sun wind and sea may soon combine to to produce clean- burning hydrogen fuel
according to to CEE researchers The team integrated water purification technology into a a a a a a a new proof-of-concept design for a a a a a a a sea water electrolyzer which uses an an electric current to split apart the hydrogen and oxygen in water molecules This new method for “sea water splitting” could make it it easier to to turn wind and and solar energy into a a a a a a a a a storable and and portable fuel
according to to Bruce Logan Kappe Professor of of Environmental Engineering and Evan Pugh University Professor “Hydrogen is a a a a a a great fuel
but you have to to to make it ” Logan said “The only sustainable way to to to do that is to to to use renewable
energy and produce it from water water You also need to to use use water water that people do not want to to use use for other things and that would be sea water So the the holy grail of producing hydrogen would be to combine the the the sea water and and and the the wind and and and solar energy found in in in coastal and and and offshore environments ” Despite the abundance of sea water water it it it is not commonly used for water water splitting Unless the the water is desalinated prior to entering the the the electrolyzer—an expensive extra step—the chloride ions in in in in sea water turn into into toxic chlorine gas which degrades the the equipment and seeps into into the the environment To prevent this the researchers inserted a a a a a thin semipermeable membrane originally developed for purifying water in in in the reverse osmosis (RO) treatment process The RO RO membrane membrane replaced the ion-exchange membrane membrane commonly used in electrolyzers “The idea behind RO is that you put a a a a a a really high pressure on the the water and and push it through the the the membrane and and keep the the chloride ions behind ” Logan said In an electrolyzer sea water would no longer be pushed through the RO membrane membrane but contained by it A membrane membrane is used to help separate the reactions that occur near two submerged electrodes—a positively charged charged anode and a a a a a a a a negatively charged charged cathode—connected by an an an external power power source When the power power is turned on water molecules start splitting at at the anode releasing tiny hydrogen ions called protons and Christopher Gorski