摘要:
The invention provides a process for making 1,2-dichloroethane by subjecting ethylene to an oxychlorination reaction with hydrogen chloride and a gas containing molecular oxygen, in gas phase, at elevated temperature and in contact with a fluidized bed catalyst of copper-II-chloride on a carrier, wherein the reaction gases are cooled under pressure in two condensation stages, condensed 1,2-dichloroethane and water are removed, the bulk of unreacted starting gas and inert gas are recycled, the reaction gases coming from the second condensation stage are delivered to a third condensation stage, cooled therein under pressure down to a temperature within the range 5.degree. to 18.degree. C. and to the extent necessary to retain in the recycle gas 0.5 to 3 volume % of 1,2-dichloroethane, and the recycle gas is admixed, directly upstream of the reactor, with a quantity of pure oxygen necessary to replace consumed oxygen. The present process provides more specifically for preheated hydrogen chloride to be wholly or partially introduced into the recycle gas heated to 150.degree. to 200.degree. C. and for the latter to be then admixed with pure oxygen, the oxygen being admitted at a point lying between the hydrogen chloride feed point and the feed point of the recycle gas into the reactor.
摘要:
1,2-dichloroethane is made by subjecting ethylene to an oxychlorination reaction with hydrogen chloride and a gas containing molecular oxygen in gas phase, at elevated temperature and in contact with a fluidized bed copper-II-chloride catalyst on a carrier, wherein the reaction gases are cooled under pressure in two condensation stages, condensed 1,2-dichloroethane and water are removed and the bulk of unreacted starting gas and inert gas are recycled. More specifically the reaction gases are delivered to a third condensation stage and cooled therein under pressure down to a temperature within the range 5.degree. to 18.degree. C. and to the extent necessary for the recycle gas to contain 0.5 to 3 volume % of 1,2-dichloroethane. Next, the recycle gas is directly admixed upstream of the reactor, with a quantity of pure oxygen necessary to replace consumed oxygen and re-establish an oxygen content of 12 to 25 volume % therein.
摘要:
A cooling device for quenching hot, highly corrosive combustible gases containing chlorine and hydrogen chloride comprises an elongated steel vessel having rounded top and bottom end portions, an inlet connection on the top end portion, a plurality of inclined connections in the top end portion to facilitate injection of quenching liquid, a lateral outlet connection in the lower third of the steel vessel for quenched combustion gases and quenching liquid, an axial outlet connection on the bottom end portion of the steel vessel for cleaning purposes and also providing an outlet for the quenching liquid, an acid-resistant hard rubber lining extending over the interior surfaces of the steel vessel and all connections, an acid-resistant ceramic lining on the hard rubber lining, and a refractory lining in the upper portion of the steel vessel on the acid-resistant lining. The innermost surface of the cooling device comprises a lining of further acid-resistant material which forms an interior cylindrical wall of equal diameter throughout.
摘要:
1,2-dichloroethane is continuously and completely removed and recovered from the off-gas obtained during the production of 1,2-dichloroethane by subjecting ethylene to an oxychlorination reaction with hydrogen chloride and oxygen. The off-gas is initially contacted with active carbon, then incinerated at temperatures higher than 900.degree. C. and ultimately freed from hydrogen chloride and chlorine, and the active carbon is freed from 1,2-dichloroethane and regenerated by treating it with hot steam. More particularly, the off-gas loaded with the 1,2-dichloroethane and having a temperature of 1.degree. C. to 10.degree. C. is heated to a temperature at least 20.degree. C. higher than the respective dew point of water and contacted with the active carbon.
摘要:
In a process for the production of alloys from at least two alloy components (A, B, C, D, . . . ) with different melting points by melting in an inductively heated cold-walled crucible (1) with a cooled crucible base (3), in order to obtain an exact and homogeneous alloy composition at least a part of the alloy components (A, B, C, D, . . . ) are introduced into the cold-walled crucible (1) consecutively and in stacked fashion where either a) the alloy component (a) in each case with the lower melting point is introduced first or b) the alloy component in each case with the lower density is introduced first and following the introduction at least one of further alloy component the heating energy is switched on. The process serves preferably for the production of the intermetallic phase TiAl, where firstly the aluminium and then the titanium are stacked in the cold-walled crucible (1).
摘要:
The disclosure relates to a process for making 1,2-dichloroethane by reacting ethylene with chlorine in a solvent in the presence of a catalyst, at a temperature of about 20.degree. to 200.degree. C. at atmospheric or elevated pressure, and distillatively separating the 1,2-dichloroethane from the chlorination mixture. The disclosure provides more particularly for the catalyst used to be an anhydrous tetrachloroferrate(1-) or a substance capable of forming a tetrachloroferrate(1-) in the reaction mixture.
摘要:
The invention relates to a method as well as a device for closed-loop control of the electrode gap in a vacuum arc furnace (10), wherein an electrode gap of a melting electrode from the surface of a melt material is subjected to closed-loop control as a function of a droplet short-circuit rate. For this purpose, a histogram (70) of detected droplet short-circuits (80) is created on the basis of at least one droplet short-circuit criterion (76), the histogram (70) is subdivided into sub-areas (72), a characteristic sub-area (74) of the histogram (70) is selected for closed-loop control purposes, and an electrode gap is subjected to closed-loop control on the basis of the droplet short-circuits (80) which can be associated with the selected sub-area (74).
摘要:
In an electroslag remelting point with a mold (4) for forming an ingot from the remelted material of at least one consumable electrode (33), with a body (6) having at least one vertically driven electrode rod (15) for advancing a respective consumable electrode (33), and with a hood (19) which is disposed above the mold (4) and has at least one opening (18) which is concentric with the respective electrode axis (A), a pot-shaped boiler (20) is provided which accommodates the mould (4) and can be joined to the hood (19) to form a chamber (34) which is closed all round, completely encompasses the mould (4, 28) and can be connected via pipelines (22, 23) to a vacuum pump and/or a gas source, so that the chamber (34) can be evacuated or filled with an inert gas.
摘要:
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. under a pressure of about 1 up to 15 bars, the mean sojourn time of the reaction mixture in the mixing zone and reaction zone being equal to about 1 to 15 hours;(b) for a portion of liquid reaction mixture to be removed from the reaction zone and subdivided into two streams, for one of these streams to be passed through a heat exchanger for the abstraction of calorific energy and reduction of its initial temperature, and for it to be recycled to the mixing and reaction zone; for the second stream to be introduced into an expansion vessel and for proportions corresponding to the quantity of reaction product formed in the reaction zone to be evaporated therein; for resulting vaporous matter to be introduced into a fractionating column, unevaporated liquid matter of the second stream being recycled into the liquid medium circulated in the mixing and reaction zone; and(c) for 1,2-dichloroethane to be distillatively separated from the vaporous matter introduced into the fractionating column with the use of a portion of the heat energy transferred inside the heat exchanger and for the 1,2-dichloroethane to be removed overhead.
摘要:
Chlorine is reacted with excess tin in liquid tin(IV) chloride at 20.degree. to 90.degree. C., 30 to 300 dm.sup.3 (S.T.P.)h.sup.-1 of chlorine being passed in per dm.sup.3 of tin(IV) chloride present in the reaction chamber and 0.08 to 0.3 dm.sup.3 h.sup.-1 of tin(IV) chloride being recycled with cooling per 1 dm.sup.3 (S.T.P.)h.sup.-1 of chlorine passed in. An excess of tin of at least 4 times the weight of chlorine passed in per hour is maintained. An amount of tin(IV) chloride is taken out of the cycle such that the level of the tin(IV) chloride in the reaction chamber remains approximately constant. The tin(IV) chloride taken off is brought into contact at 60.degree. to 110.degree. C. for an average residence time of 1 to 7 hours with tin in liquid tin(IV) chloride, thereafter filtered and, if appropriate, treated with absorbing agents. Pure, ready-for-use tin(IV) chloride is obtained continuously without a purification by distillation in a simple, readily cleanable apparatus made of a cheap material.