Abstract: A process and apparatus for pneumatic flotation include thinning a conditioned and gassified pulp and then forming them in the separation chamber into an enclosed free jet.

Abstract: The invention relates to a process for the continuous preparation of organic isocyanates, preferably polyisocyanates, through the reaction of organic amines, preferably polyamines, with phosgene in the presence of organic solvents under pressure, for example from 5 to 100 bar, at elevated temperatures, for example from 100 to 220.degree. C., whereby the reaction mixture is partially recycled, preferably using natural circulation, and the hydrogen chloride content in the reaction mixture prior to the addition of the amine is less than 0.5 percent by weight based on the total weight of the reaction mixture and the molar ratio of phosgene to NH.sub.2 group in the organic amines is from 12:1 to 200:1.

Abstract: A process for the removal of fission-product inert gases from the waste gs of a reprocessing plant for nuclear fuel materials in which the nuclear fuel is subjected to comminution and, after burning off of graphitic components, is subjected to chemical solubilization, e.g. in an acid. During the solubilization, a sparging gas is passed through the solution which entrains with it the waste gases from the solubilizer or digestion vessel. After acid recovery, the gas phase is filtered and collected, a portion of the gas phase, constituting the sparging gas, is recirculated to the solubilizing unit and consists predominantly of fission-product inert gas (generally xenon, krypton and krypton isotopes).