Ann: Corporate Update - Noosa Mining Conference, page-53

Yes caesium seems to be the go to as catalyst material for sufuric acid
production. Not sure when Albemarle will stop producing it.
Something I found interesting while looking at DuPont.
DuPont Clean Technologies wins sulfuric acid plant contract from ioneer
(subject to FID) for the Rhyolite Ridge lithium project.
" Electricity will be generated by recovering the heat released in the process
and producing steam. An initial 35MW will be generated by the plant, which
is enough to power the entire operation at Rhyolite Ridge, meaning ioneer
will not need to draw power from the grid. Ioneer stated that Rhyolite Ridge
will be an energy-independant operation that will use primary co-generated,
zero carbon power."