Abstract: A tray column is proposed which includes column trays, two or more supports which are arranged on the underside of the column trays and support them and a bearing ring for the column trays on the inner wall of the tray column, wherein three-way joints of inner column wall, bearing ring and support are prevented by cutouts in the bearing ring.

Abstract: A hydraulically sealed crossflow mass transfer tray, separating columns which contain the hydraulically sealed crossflow mass transfer tray and the use of such separating columns for thermal separating processes.

Abstract: A tray column is proposed which comprises column trays, two or more supports which are arranged on the underside of the column trays and support them and a bearing ring for the column trays on the inner wall of the tray column, wherein three-way joints of inner column wall, bearing ring and support are prevented by cutouts in the bearing ring.

Abstract: The invention relates to a method for producing a highly pure, aqueous hydroxylamine solution by distilling an aqueous solution, devoid of salt, of a hydroxyl ammonium salt in a plate column comprising at least two mechanical plates. Said method is characterised in that packing bodies are arranged between at least two plates of the plate column over the cross-section of said column.

Abstract: A process for preparing a salt-free aqueous hydroxylamine solution by distilling an aqueous solution of a hydroxylammonium salt and a base in a tray column having at least two mechanical trays, wherein random or structured packings are located above at least one tray of the tray column over the cross section of the column.

Abstract: A process for the isolation of amines from aqueous solutions by continuous distillation of aqueous solutions of the amines by a two-pressure method of rectifying aqueous solutions of amines which form with water an azeotrop, the composition of which is pressure-dependent, in two columns at different pressures provided that: a) the pressure in the second column is set to a value at least 0.5 bar higher than in the first column, b) the aqueous amine solution is fed, as a side stream, to the first column, and water and portions which boil at a higher temperature than the amine or which are non-volatile are removed at the base of the column, c) a mixture of amine and water is withdrawn at the head of the first column and fed, as a side stream, to the second column, d) an azeotrope of water and amine is withdrawn at the head of the second column and recycled to the first column, and (e) the purified amine is discharged at the base of the second column.

Abstract: The invendon relates to a method for the production of a salt-free aqueous hydroxylamine solution by distilling an aqueous solution of an hydroxylammonium salt and a base in a plate column having at least two mechanical plates. The invention is characterized in that packings or structured packings are placed above at least one of the plates of the plate column along the cross section of said column.

Abstract: The invention relates to a method for producing a highly pure, aqueous hydroxylamine solution by distilling an aqueous solution, devoid of salt, of a hydroxyl ammonium salt in a plate column comprising at least two mechanical plates. Said method is characterised in that packing bodies are arranged between at least two plates of the plate column over the cross-section of said column.

Abstract: A hydraulically sealed crossflow mass transfer tray, separating columns which contain the hydraulically sealed crossflow mass transfer tray and the use of such separating columns for thermal separating processes.