The relative activities of a low-surface crystalline and high-surface amorphous LaOCl, further denoted as S1 and S2, have been compared for the destructive adsorption of CCl 4 . It was found that the intrinsic activity of S2 is higher than that of S1. Both samples were characterized with X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), N 2 -physisorption, and Raman and infrared (IR) spectroscopy. IR was used in combination with CO 2 , CO, and methanol as probe molecules. The CO 2 experiments showed that different carbonate species are formed on both materials. For S1, a high surface concentration of bidentate carbonate species and a lower concentration of monodentate carbonate were observed. In the case of S2, bulk carbonates were present together with bridged carbonates. CO adsorption shows that S2 and S1 have very similar Lewis acid sites. However, methanol adsorption experiments showed that S2 had a higher number of stronger Lewis acid sites than S1 and that twofold coordinated methoxy species were more strongly bound than threefold coordinated methoxy species. Because of the analogy between methanol dissociation and the removal of the first chlorine atom in the destructive adsorption of CCl 4 , the sites enabling twofold coordination were likely to be the same Lewis acid sites actively involved in the destructive adsorption of CCl 4 . La 2 O 3 was less active than the two LaOCl materials, and therefore, the intrinsic activity of the catalyst increases as the strength of the Lewis acid sites increases. S2 contains more chlorine at the surface than S1, which is expressed by the higher number of sites enabling twofold coordination. Moreover, this explains the difference in destructive adsorption capacity for CCl 4 that was observed for the samples S1 and S2. Since LaCl 3 , being the most acidic phase, is not active for the destructive adsorption of CCl 4 , basic oxygen atoms, however, remain needed to stabilize the reaction intermediate CCl 3 as La-O-CCl 3 .

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Furfural and acetic acid are produced with approximately 60 and 90 mol % yield, respectively, upon stripping bagasse with a gaseous stream of HCl/steam and condensing the effluent to water/furfural/acetic acid. The reaction kinetics is 1(st)  order in furfural and 0.5(th)  order in HCl. A process concept with full recycling of the reaction effluents is proposed to reduce the energy demand to <10 tonsteam  tonfurfural (-1) and facilitate the product recovery through a simple liquid/liquid separation of the condensate into a water-rich and a furfural-rich phase.