Raschig–Hooker process

In fact, the ability to recycle the hydrogen chloride made the Raschig–Hooker process preferable to the Dow and Bayer process, which requires its sodium chloride product to be converted into chlorine and sodium hydroxide.

While the Raschig–Hooker process does recycle the hydrogen chloride it produces, its catalyst experiences carbon deposition and must be frequently regenerated.

The harsh chemical environment, use of catalysts, and large energy consumption has made it a target for green chemistry alternatives.

In the first step, the reaction is only run to 10% to 15% conversion to prevent the second addition of a chlorine atom to the desired chlorobenzene.

Therefore, the Raschig–Hooker process needed to be run at high concentrations in large reactors to be industrially economical.