Abstract: A process for evaporating 1, 2-dichloroethane (EDC) prior to its thermal decomposition (pyrolysis) is provided so that it facilitates the heating of the liquid-phase EDC at temperatures below 100.degree. C. to meet the inlet conditions for the pyrolysis zone, while dispensing with the need for an evaporation zone and exploiting sensible heat recovery at the same time. This is achieved in that the liquid-phase EDC is first pressurized to attain a value above its critical pressure (5.36 MPa) and then heated to attain at least its critical temperature (approx. 288.degree. C.).

Abstract: A method for separating vinyl chloride, which comprises cooling a cracked gas obtained by cracking 1,2-dichloroethane by a thermal cracking furnace, firstly in a heat exchanger, then further cooling it in a quenching tower and then distilling it, wherein the cracked gas is cooled in the heat exchanger to at least 350.degree. C., the quenching tower is controlled so that from 80 to 98 wt % of the cracked gas introduced is withdrawn as an overhead product and the rest of from 20 to 2 wt % of the cracked gas is withdrawn as a bottom effluent, and they are respectively sent to the subsequent steps, and formed coke is discharged together with the bottom effluent.

Abstract: Novel .alpha.-amylase enzymes are disclosed in which one or more of residues corresponding to A210, H405 and T412 in Bacillus licheniformis are mutated. The disclosed .alpha.-amylase enzymes show altered or improved stability and/or activity profiles.

Abstract: The dehydrochlorination of 1,1,2,3,3-pentachloropropane to produce 1,2,3,3-tetrachloropropene is conducted using aqueous alkali metal hydroxide in the substantial absence of added ethanol.The 1,2,3,3-tetrachloropropene is recovered from the reaction mixture in the substantial absence of added ether. The preferred methods of recovery are steam distillation and flash distillation.

Abstract: A process for the pyrolysis of 1,2-dichloroethane (EDC) in a pyrolysis furnace (1) involves feeding liquid EDC into a convection heat transfer tube (2) for preheating, channeling an intermediate flow of preheated EDC into a radiation heat transfer tube (3) for further heating, thereby pyrolyzing a part of EDC into vinyl chloride monomer, and discharging a decomposition gas flow from the pyrolysis furnace. Potential heat is recovered from the decomposition gas by using a double tube type heat exchanger (10) consisting of outer and inner tubes, that is, by channeling the intermediate flow through the outer tube (11), channeling the decomposition gas through the inner tube (15) for heat exchange between the intermediate flow and the decomposition gas, and feeding the heat acquired intermediate flow into the radiation heat transfer tube (3).

Abstract: A thermal process for cracking 1,2-dichloroethane to form vinyl chloride comprising heating 1,2-dichloroethane in a reaction zone at a temperature between 300.degree. and 650.degree. C. under an absolute pressure between 1 and 40 bars; said heating being conducted in the presence of hydrochloric acid.

Abstract: The conversion rate in the preparation of vinyl chloride by thermal cracking of 1,2-dichloroethane is determined by measuring the absorption of high-energy radiation, the pressure and the temperature of the gases issuing from the cracking furnace.

Abstract: Methods for synthesis of chemical compounds by catalytic transfer hydrogenation comprise forming a mixture of a starting material, a hydrogen donor material and a catalyst. The catalyst is selected from a catalytic form of carbon, a polyethylene glycol phase transfer agent, and mixtures thereof. The mixture is heated at a temperature of from 30.degree. to 400.degree. C. in the presence of at least one alkali or alkaline earth metal compound to cause reduction of the starting material by catalytic transfer hydrogenation and form the desired chemical compound product.

Abstract: A method and apparatus for quenching a gas stream in the production of vinyl chloride monomer includes the use of a knock back condenser and a plurality of column fractional distillation trays disposed within the quench column, and a liquid stream of 1,2-dichloroethane, vinyl chloride, and hydrogen chloride may be removed from the bottom column fractional distillation tray.

Abstract: Vinyl chloride monomer is selectively prepared by intimately contacting, in the absence of steam, a feedstream of 1,2-dichloroethane with a flow of fluid or solid particulates heated to such elevated temperature and for such minim period of time, e.g., 0.010 to 0.5 second, as to flash transfer a dehydrochlorinating amount of thermal energy to the 1,2-dichloroethane and thereby ultrapyrolyzing at least a fraction of same into vinyl chloride and HCl, and recovering the vinyl chloride from the medium of ultrapyrolysis.

Abstract: Methods for synthesis of chemical compounds by catalytic transfer hydrogenation comprise forming a mixture of a starting material, a hydrogen donor material and a catalyst. The catalyst is selected from a catalytic form of carbon, a polyethylene glycol phase transfer agent, and mixtures thereof. The mixture is heated at a temperature of from 30.degree. to 400.degree. C. in the presence of at least one alkali or alkaline earth metal compound to cause reduction of the starting material by catalytic transfer hydrogenation and form the desired chemical compound product.

Abstract: Quaternary ammonium phase transfer catalyst is removed from the dehydrochlorination product of 3,4-dichlorobutene-1 by treatment of the organic, chloroprene-containing phase with an oxy acid which combines with the catalyst to form a separate phase.

Abstract: Active methine compounds are chlorinated by contacting such compounds with a perchloroalkane and aqueous base in the presence of a phase transfer catalyst which is an tetraalkylonium hydroxide. Chlorinated products, preferably tertiary alkyl chloro compounds, are produced. The tertiary alkyl chloro compounds are useful in elimination reactions, preferably reactions with base, to form unsaturated compounds, particularly compounds having a vinylidene or exomethylene group.

Abstract: An addition of benzotrichloride produces a significantly higher yield of vinyl chloride in the thermal cleavage of 1,2-dichloroethane.

Abstract: A process for hydrodehalogenating halogenated organic compounds present in a contaminated aqueous environmental source in which the halogenated organic compounds are reacted with hydrogen gas or a source of hydrogen gas in the presence of a catalyst of palladium on carbon.

Abstract: Process for producing vinylchloride monomer by pyrolysis of 1,2-dichloroethane comprising carrying out heat exchange between a high temperature cracked gas produced as a result of the pyrolysis product and the 1,2-dichloroethane which is introduced into the pyrolysis furnace with a flow rate of the cracked gas at 5 m/s or more but less than 20 m/s until the cracked gas is cooled down to 180.degree.-350.degree. C. and introducing the 1,2-dichloroethane into the furnace for the pyrolysis.

Abstract: The present invention provides a process for preparing a 1,1-disubstituted ethylene derivative of the formula ##STR1## which comprises reacting lead with a carbinol derivative of the formula ##STR2## wherein R.sup.1, R.sup.2, R.sup.3, X, Y, m and n are defined in the specification. The reaction is conducted more advantageously in the presence of a metal having higher ionization tendency than lead.

Abstract: The invention relates to a process for the production of vinyl chloride by starting from dichloroethane, wherein dichloroethane is heated, without being vaporized, in the convective section of an oven, it is then vaporized by indirect heat exchange with air or another fluid, which is heated in its turn by exploiting the heat of the cracking products leaving that oven, and containing monomer vinyl chloride.Dichloroethane, as vapor, is introduced into the radiant section of the oven, wherein it undergoes the cracking and forms vinyl chloride and, if it has been used, a portion of the air heated by the heat of the cracking products can be delivered to the oven burners.The system for carrying out the process is illustrated in FIGS. from 1 to 3, and to them reference is made.

Abstract: In a method of treating the reaction product of pyrolysis of 1,2-dichloroethane to form vinyl chloride and hydrogen chloride with multiple stage cooling and distillation separation of the reaction product and recycle of unreacted 1,2-dichloroethane to the pyrolysis step, the improvement comprising direct cooling of the reaction product immediately after leaving the pyrolysis step, within 1 sec from a temperature range of 480.degree. to 540.degree. C. down to 150.degree. to 250.degree. C.

Abstract: An unsaturated halohydrocarbon such as vinylidene chloride is produced by the dehydrohalogenation of haloalkanes such as 1,1,1-trichloroethane or 1,1,2-trichloroethane, in the presence of a novel mixed salt catalyst containing a Group IA metal cation such as Cs, a Group IIA metal cation such as Mg and a neutralizing number of counter anions such as chloride distributed on a support such as silica.

Abstract: The hot, vinyl chloride-containing gases leaving the cracking furnace heat liquid 1,2-dichloroethane in a first container to the boiling point or to its immediate vicinity, and the 1,2-dichloroethane is transferred into a second container in which it is partly evaporated under a lower pressure than in the first container. The evaporated 1,2-dichloroethane is fed into the cracking furnace, and the nonevaporated 1,2-dichloroethane is fed back into the first container. By supplying fresh, optionally prewarmed 1,2-dichloroethane into the second container, the amount of product evaporated therein is replaced, the prewarming advantageously being regulated through the level of the liquid 1,2-dichloroethane in the second container. The prewarming of the 1,2-dichloroethane can take place in the convection zone of the cracking furnace or by means of a temperature-control medium, for example steam, which has been heated in the convection zone of the cracking furnace.

Abstract: An improved method of producing vinyl chloride by pyrolysis of purified 1,2-dichloroethane at temperatures from 480.degree. C. to 540.degree. C. at a pressure of 10 to 36 bar absolute with partial utilization of the heat content of the flue gases from the pyrolysis furnace firing to preheat liquid 1,2-dichloroethane almost to its boiling temperature utilizing the flue gas waste heat to generate steam, cool the pyrolysis gas mixture in several stages and separate the hydrogen chloride from the pyrolysis gas mix in a hydrogen chloride column as well as separate vinyl chloride from the pyrolysis gas mix in a vinyl chloride monomer column.

Abstract: Ferric chloride (FeCl.sub.3), a known chlorination and polymerization catalyst for 1,3-butadiene ("BD"), can nevertheless be effectively used in a packed or trayed quench tower, operating under essentially anhydrous conditions, without plugging it. Essentially all BD from a crude stream of vinyl chloride (VCl), is removed within a hold-up time of 6 minutes. The speed of removal is note-worthy because less than half the stoichiometric amount of chlorine required to chlorinate the BD is used. The BD is preferentially chlorinated, the time being too short to chlorinate a substantial amount of chloroprene and monovinylacetylene. Only a portion of the BD is removed by chlorination, the remainder being removed by polymerization catalyzed by 100-200 ppm anhydrous FeCl.sub.3.

Abstract: An improved process for the preparation of vinyl chloride from 1,2-dichloroethane (EDC) wherein 0.10 to 0.15 % by weight of carbon tetrachloride based on EDC, is used as a cracking promoter and the CHCl.sub.3 content is limited to less than 200 ppm. Before being fed to the cracking zone, the EDC is brought almost to the boiling point at 15 to 31 bar and then expanded to 10 to 16 bar with flashing EDC vapors and the fraction which has remained liquid is vaporized externally, and the combined EDC gas streams are heated, after being fed into the cracking furnaces, so that the energy required for cracking is already supplied in the first 75 to 85% of the reaction zone, whereby a conversion of 60 to 70% is obtained at residence time from 10 to 25 seconds and the exit temperature from the reaction zone is 485.degree. to 510.degree. C.

Abstract: A process for the preparation of vinyl chloride by vaporizing liquid 1,2-dichloroethane, thermally cracking the 1,2-dichloroethane and cooling the hot reaction mixture by means of cooled and condensed portions of the reaction mixture, wherein a defined amount of the 1,2-dichloroethane is taken off as liquid in or downstream of the vaporizer and mixed with a defined amount of the cooled liquid portion of the reaction mixture, the mixture is distilled and the constituents taken off the top of the distillation column are mixed with the liquid 1,2-dichloroethane upstream of the vaporizer while the constituents taken off the bottom of the distillation column are worked up by distillation.

Abstract: The energy requirements for preparing vinyl chloride monomer can be reduced by a process which includes the steps of purifying by distillation ethylene dichloride, compressing the ethylene dichloride vapor from the distillation column to a temperature and pressure sufficient for direct feed to a pyrolysis furnace. Up to 80% of the heat presently used after distillation and before pyrolysis can be saved.

Abstract: This process stems from the discovery that the solubility of water in vinyl chloride monomer ("VCM") is so low in a cold aqueous caustic solution at a temperature below 0.degree. C., that the aqueous solution will remove water dissolved in the monomer, and at the same time, will neutralize the HCl associated with the monomer and prevent the formation of acetylene. This discovery makes it possible to dry and neutralize a HCl and water-containing vinyl chloride ("VCl") stream, by intimately contacting the stream with a cold aqueous 2 to 30 wt % caustic soda solution at a temperature below 25.degree. F. and above the freezing point of the caustic solution. In a commercial VCM producing facility, VCl can be "finished" in a "stand-alone" processing facility with greater economy than in a conventional VCM plant, yet avoid the hazards of operating a conventional VCl stripping column and scrubbers packed with solid caustic pellets.

Abstract: A method for the preparation of a first sulfone compound of the formula: ##STR1## wherein R.sub.a is ##STR2## where R.sub.b is Br and R.sub.c is H except that R.sub.b and R.sub.c together may be an electron pair when R.sub.6 is a radical of the formula: ##STR3## wherein X.sub.1 is independently chlorine, bromine or iodine and R.sub.1 and R.sub.2 are independently at each occurrence hydrogen or, substituted or unsubstituted, phenyl or alkyl where the substituents are halogen or alkoxy or additional --SO.sub.2 Br groups; provided that, each carbon atom of R.sub.1 or R.sub.2 which contains --SO.sub.2 Br also contains an X.sub.1 group and wherein R.sub.3 through R.sub.9 are independently --OZ,--C.sub.6 M.sub.5,--Z,--SiZ.sub.3 or --X.sub.2, where Z is hydrogen or substituted or unsubstituted phenyl, alkyl, alkenyl or alkynyl; X.sub.2 is chlorine, bromine, iodine or fluorine; M is independently at each occurrence Z or X.sub.2 ; R.sub.3 and R.sub.4 may together be an electron pair; two or more of R.sub.3, R.sub.

Abstract: A process is disclosed for the economical operation of a commercial ethylene dichloride (EDC) cracking furnace which typically is prone to coking of the tubes through which the EDC is flowed. The EDC cracking furnace is found to be critically sensitive to the presence of trace amounts, 30 ppm or more of FeCl.sub.3 and/or 20 ppm or more of free chlorine, which cause coking of the tubes of the furnace. The coking of the tubes is minimized by maintaining less than 30 ppm by weight of FeCl.sub.3 or less than 20 ppm of free chlorine in the EDC feed to the EDC furnace. In the particular instance where EDC is produced at least in part in a high temperature direct chlorination ("boiling") reactor constructed from mild steel, this goal requires that the chlorine content of the effluent from the boiling reactor be controlled so as not to exceed 20 ppm. But this is to be done without using more than a 2% by weight excess of ethylene over the stoichiometric amount required to produce the EDC in the boiling reactor.

Abstract: 1,2-Dichloroethane is pyrolyzed in a pyrolysis furnace to produce a stream comprising vinyl chloride and 1,2-dichloroethane. The stream is removed from the furnace and introduced to essentially unheated conduit means to establish a stream flowing in the conduit means. Pyrolysis promoter is introduced to the stream in the conduit means and sensible heat of the stream is utilized in the conduit means to pyrolyze further amounts of 1,2-dichloroethane and to increase the yield of vinyl chloride.

Abstract: Saturated C.sub.1-6 hydrochlorocarbons are dehydrochlorinated by contacting with ZSM-5 or silicalite zeolites at 200.degree. C.-400.degree. C.

Abstract: The description covers a process for the manufacture of vinyl chloride by thermal cracking of 1,2-dichloroethane. The hot gas leaving the reaction furnace is cooled to the inlet temperature of the column in which the hydrogen chloride is separated from the products of thermal cracking of the 1,2-dichloroethane. Within the range of 560.degree. to 480.degree. C. and of 220.degree. to 120.degree. C., one or more cooling stages are applied through which the reaction gas mixture passes at high flow velocity, the cooling device being preferably a single-tube cooler. Starting from about 220.degree. C., a liquid substantially consisting of 1,2-dichloroethane may be added intermittently. The heat transferred to the coolant in the stages of indirect cooling is preferably reused within the vinyl chloride manufacturing process.

Abstract: There is disclosed a process for the production of hexachlorocyclopentadiene comprising the steps of:1. Reacting liquid cyclopentadiene and chlorine at a temperature of from about 0.degree. to about 100.degree. C. until an average of at least 4 chlorine atoms has been added per mole of cyclopentadiene to form a first-stage product;2. heating the resultant liquid reaction product of Step 1 in a second stage at a temperature of from about 140.degree. C. to below about 200.degree. C. with chlorine in the presence of from about 0.0001% to about 5.0% (by weight) of an aromatic compound until the reaction products of Step 1 contain an average of about 6 chlorine atoms per molecule, based on cyclopentadiene starting material; wherein said aromatic compound contains from 1 to 3 aromatic rings; at least one of the rings containing a nitrogen atom;3. vaporizing and heating the resulting reaction products of Step 2 in a third stage in the presence of chlorine to a temperature of above 450.degree. C.

Abstract: Process and apparatus for producing vinyl chloride monomer characterized by conjoint chlorination and dehydrochlorination reactions carried out in the presence of fluidized solids which provide efficient heat transfer within and between the two reaction zones.