Contact process
However, the Lead Chamber process is indeed a method used for the production of sulfuric acid, but it's an older method.
Lead Chamber process:
This process was used from the 18th century until the early 20th century. It involves the oxidation of sulfur dioxide (SO2) to sulfur trioxide (SO3) using nitric oxide (NO) as a catalyst in the presence of water.
Contact process:
This is the modern method used for the production of sulfuric acid. It involves the oxidation of sulfur dioxide (SO2) to sulfur trioxide (SO3) using vanadium pentoxide (V2O5) as a catalyst.