Abstract: The disclosure relates to a process for making 1,2-dichloroethane by reacting ethylene and chlorine in a reaction zone having a liquid medium containing chlorinated C.sub.2 -hydrocarbons circulated therein. To this end, the disclosure provides:(a) for approximately equimolar proportions of ethylene and chlorine to be introduced into the circulated liquid medium; for the whole to be reacted in a reaction zone at a temperature of about 75.degree. up to 200.degree. C.

Abstract: The invention relates to process for making phosphorus pentoxide by subjecting elementary phosphorus to a combustion reaction with the aid of air, the reaction heat being utilized for the production of energy. To this end, the invention provides for the phosphorus to be subjected to combustion with dry air containing, per m.sup.3, 5 g down to 0.01 g of water, inside a combustion chamber of which the metallic walls are arranged so as to form a cooling system with cavities therein and for a liquid and liquid/steam-mixture, respectively, to be circulated through the cooling system under pressure within the range 1 to 150 bars, the liquid or mixture assuming a temperature of more than 150.degree. C. up to 500.degree. C. Steam which is formed in the cooling system is continuously taken therefrom and replaced by an equivalent proportion of fresh liquid.

Abstract: A distillation column comprising a shell which has serially arranged therein a plurality of distilling trays with respective liquid inlets and outlets. An annular slit of substantially uniform width is left between the individual trays and the shell. The slit may be interrupted by a plurality of spacers which bear against the inner surface of the shell, and the spacers are provided around the periphery of the individual trays.