Stolzenberg established a chemical incineration facility and a site to convert chlorine gas and diphosgene. Exposure to diphosgene is similar in hazard to phosgene. Diphosgene is a chemical compound with the formula ClCOCCl. Diphosgene converts to phosgene upon heating or upon catalysis with charcoal. Other Green Cross mixtures were based on phosgene and/or diphosgene. Diphosgene is used in some laboratory preparations because it is easier to handle than phosgene.