Abstract: The present invention relates to a process for recovering raw materials from a polyurethane foam, comprising step (A), the providing of a polyurethane foam based on an isocyanate component and a polyol component, wherein the polyurethane foam comprises a cell structure containing one or more volatile accompanying substances, namely a component X selected from the group consisting of oxygen, a blowing agent, a disinfectant and a mixture of two or more of the above, wherein component X comprises at least oxygen, step (B), the chemolysis of the polyurethane foam with a chemolysis reagent, wherein the polyurethane foam is degassed before being contacted with the chemolysis reagent, wherein at least oxygen, but preferably all constituents of component X or any gaseous breakdown products thereof that have formed are removed from the chemolysis apparatus in gaseous form via a gas removal device at a pressure of not more than 960 mbar(abs.) and a temperature of not more than 120° C.

Abstract: A method of processing a powdery material for additively manufacturing a workpiece (22) comprises the steps of: (a) providing a device (15) for receiving a powder bed (20) of the powdery material to be machined and a beam generator (12) adapted to direct an energy beam (13) to laterally different locations of the powder bed (20); b) applying the powdery material in layers to the powder bed (20); c) irradiating an area (30; 30a; 30b; 30c) in the powder bed (20) with the energy beam (13), wherein the area (30; 30a; 30b; 30c) is composed of a plurality n of points P1 . . . Pn arranged in two dimensions, which are irradiated one after the other. In order to improve the scanning strategy during step c), it is provided that at least once during the irradiation of the area two successively irradiated points Pi, Pi+1 are spaced apart from each other in such a way that in each of the two dimensions at least one other point P1 . . . Pi?1, Pi+2 . . .

Abstract: The invention relates to a method for recovering raw materials from polyurethane products, having the steps of: (A) providing a polyurethane product based on an isocyanate component and a polyol component; (B) reacting the polyurethane product with an alcohol in the presence of a catalyst, wherein a first product mixture containing alcohol, polyols, carbamates, and optionally water is obtained; (C) preparing the first product mixture, having the steps of: (C.I.) mixing the first product mixture obtained in step (B) with an organic solvent, which can be mixed with the alcohol used in step (B), optionally followed by a separation of solid components, thereby obtaining a second product mixture; (C.II) washing the second product mixture obtained in step (C.

Abstract: The invention relates to a method for preparing a toluylene diamine mixture which, along with toluylene diamine (TDA), also contains a high-boiling fraction, such as the high-boiling fraction which is accumulated as a sump flow in the distillative preparation of product mixtures obtained by hydrogenating dinitrotoluene.

Abstract: The invention relates to a method for recovering raw materials from polyurethane products, comprising the steps of (A) providing a polyurethane product that is based on an isocyanate component and a polyol component; (B) reacting the polyurethane product with a (mono- or polyvalent) alcohol in the presence of a catalyst, thereby obtaining a first product mixture; (C) obtaining the polyols from the first product mixture, comprising (C.I) mixing, without prior removal of any water that might be contained in the first product mixture, the first product mixture obtained in step (B) with an organic solvent that is not completely miscible with the alcohol used in step (B), and phase separation into a first alcohol phase and a first solvent phase; (C.II) processing the first solvent phase and obtaining polyols; and preferably (D) obtaining amines.