Abstract: Improved hydrochlorination reactors, which have a larger internal volume and hence functional capacity than presently available hydrochlorination reactors, may be prepared with reactor walls having inner and outer layers where each layer provides a unique benefit, the inner layer having hydrogen chloride resistance and the outer layer having high strength at elevated temperature and pressure. Alternatively, or additionally, hoops may be disposed along the outside of the reactor wall to provide additional strength to the reactor during operation. Specified materials may be used to form the reactor wall in order to provide both acid resistance and high strength at elevated operating temperatures.