Abstract: A distillation-reactor for separating constituents of a feedstock having similar boiling points includes at least one stage with containing screens defining a series of containment volumes for a heterogeneous particulate catalyst. The catalyst is fluidized within the volumes defined by the containing screens by the action of vapor passing through the tray. Liquid flowing across the tray intimately contacts the fluidized catalyst and vapor without the occurrence of liquid back-up or high pressure drop.

Abstract: In a reduced-pressure process for distilling crude maleic anhydride recovered by separation from an organic absorbent wherein reduced pressure is obtained using a liquid ring-seal vacuum pump, the improvement which comprises sealing the liquid ring-seal vacuum pump by circulating a maleic anhydride absorbent from a regenerating zone through the vacuum pump chamber.

Abstract: A process for the production of polymeric carbamate from polyalkylene polyamines which provides for the efficient separation of the product mixture into a hydrocarbon phase containing the carbamate and a polyamine phase containing the polyamine hydrochloride salt utilizes an excess of polyamine reactant containing a limited amount of water. The process is particularly suited to the production of monocarbamate.

Abstract: A process for recovery of good color stability maleic anhydride which comprisesA. removing maleic anhydride from a gaseous mixture containing maleic anhydride by absorption into an organic absorbent,B. distilling maleic anhydride overhead from the resulting absorbent in a first distillation column,C. condensing maleic anhydride out of the resulting overhead thereby obtaining condensed liquid maleic anhydride,D. passing at least a portion of the condensed maleic anhydride to the upper part of a second distillation column, andE. distilling material more volatile than maleic anhydride out of the condensed liquid maleic anhydride in a second distillation column, thereby obtaining stripped maleic anhydride which is withdrawn from the lower part of the second distillation column.Preferably the stripped maleic anhydride is distilled in a third distillation column and purified maleic anhydride is withdrawn as an overhead product.