Abstract: A cracking furnace for naphtha and other hydrocarbons or, in general, for the rapid heating of a fluid feed stack has one or more tubular elements satisfying the following conditions: d.sub.h 32 F/U.ltoreq.40mm, and D/d.gtoreq.2, wherein: d.sub.h =the hydraulic diameter of the flow passage defined as the ratio of the flow cross-sectional area to the inner peripheral dimension therearound; F=the flow cross-sectional area; U=the inner peripheral dimension of the flow cross section; d=the cross-sectional height of the flow cross section; and D=the width of the flow cross section.

Abstract: To obtain olefins by the thermal cracking of hydrocarbons, e.g., vacuum gas oil, by hydrogenation and subsequent steam cracking, an intermediate fractionation of the hydrogenate is provided so that the light fraction enriched in branched isomers can be used as fuel and the heavy fraction only is subjected to the steam cracking.

Abstract: To obtain olefins by the thermal cracking of hydrocarbons, e.g., vacuum gas oil, by hydrogenation and subsequent steam cracking, an intermediate fractionation of the hydrogenate is provided so that the light fraction enriched in branched isomers can be used as fuel and the heavy fraction only is subjected to the steam cracking.

Abstract: A method and device of treatment of cocoa butter-containing masses, particularly molten chocolates, destined for subsequent processing, particularly in coating machines, the method comprising the steps of mildly cooling the mass from a first temperature of approximately 45.degree. to 50.degree. C. which is above the highest melting point of the mass to a second temperature at which pre-crystallization in the mass is initiated, sensing the occurrence of heat-producing processes in the mass during the cooling thereof, terminating the cooling upon the occurrence of such heat-producing processes, and thereafter mildly heating the mass, without overheating, to a third temperature of approximately 33.degree. to 34.degree. C., at which the mass is ready for said subsequent processing. The second temperature is thus automatically adjusted to the lowest possible value, which is desirable for the processing properties of the mass.

Abstract: In a process for the production of olefins in two stages wherein, in the first stage, heavy petroleum fractions are hydrogenated in the presence of hydrogen and a hydrogenation catalyst and, in the second stage, the thus-hydrogenated fractions are subjected to thermal cracking in the presence of steam, the improvement which comprises employing as the hydrogenation catalyst a support-free catalyst consisting essentially of elements from Groups VIb, VIIB, and VIII of the periodic table of the elements in the form of the metals, metal oxides, metal sulfides, or organometal complexes, or mixtures thereof.

Abstract: In a process for the production of olefins in two stages wherein, in the first stage, heavy petroleum fractions are hydrogenated in the presence of hydrogen and a hydrogenation catalyst and, in the second stage, the thus-hydrogenated fractions are subjected to thermal cracking the presence of steam, the improvement which comprises employing as the hydrogenation catalyst a zeolite of the faujasite structure combined with elements from Groups VIB, VIIB and VIII of the periodic table of the elements, wherein the alkali component of the zeolite is exchanged at least partially for ammonium, hydronium, alkaline earth and/or rare earth ions, and the elements are present in a metallic, ionic, oxidic and/or sulfidic form.

Abstract: A tube furnace for the cracking of organic feed stock, e.g. naphtha to ethylene, comprises a chamber traversed by at least one conduit system for the organic feed stock. The conduit system in the region of the inlet comprises a plurality of pipes which are united at an intermediate location and communicate jointly with a single pipe forming the discharge portion of the duct system. Preferably the flow cross section of the duct system increases from the inlet to the outlet end. Burners are provided in the wall of the chamber.

Abstract: Confectionery articles are coated with precrystallized, molten tempered chocolate by forcing the chocolate under pressure through a nozzle onto a veil plate to produce a downwardly descending film of chocolate under gravitational force, passing the confectionery article through said film, collecting unused chocolate and recirculating the unused chocolate through said nozzle.

Abstract: A tube furnace for the cracking of organic feed stock, e.g. naphtha to ethylene, comprises a chamber traversed by at least one conduit system for the organic feed stock. The conduit system in the region of the inlet comprises a plurality of pipes which are united at an intermediate location and communicate jointly with a single pipe forming the discharge portion of the duct system. Preferably the flow cross section of the duct system increases from the inlet to the outlet end. Burners are provided in the wall of the chamber.