Ethylene dichloride Reactions

Ethylenediamine is derived from an ammonia and ethylene dichloride reaction as shown in Figure 10.29. 

Prepare a saturated solution of sodium sulphide, preferably from the fused technical sodium polysulphide, and saturate it with sulphur the sulphur content should approximate to that of sodium tetrasulphide. To 50 ml. of the saturated sodium tetrasulphide solution contained in a 500 ml. round-bottomed flask provided with a reflux condenser, add 12 -5 ml. of ethylene dichloride, followed by 1 g. of magnesium oxide to act as catalyst. Heat the mixture until the ethylene dichloride commences to reflux and remove the flame. An exothermic reaction sets in and small particles of Thiokol are formed at the interface between the tetrasulphide solution and the ethylene chloride these float to the surface, agglomerate, and then sink to the bottom of the flask. Decant the hquid, and wash the sohd several times with water. Remove the Thiokol with forceps or tongs and test its rubber-like properties (stretching, etc.). 

Chlorine reacts with saturated hydrocarbons either by substitution or by addition to form chlorinated hydrocarbons and HCl. Thus methanol or methane is chlorinated to produce CH Cl, which can be further chlorinated to form methylene chloride, chloroform, and carbon tetrachloride. Reaction of CI2 with unsaturated hydrocarbons results in the destmction of the double or triple bond. This is a very important reaction during the production of ethylene dichloride, which is an intermediate in the manufacture of vinyl chloride ... 

Polyamines can also be made by reaction of ethylene dichloride with amines (18). Products of this type are sometimes formed as by-products in the manufacture of amines. A third type of polyamine is polyethyleneimine [9002-98-6] which can be made by several routes the most frequently used method is the polymeriza tion of azitidine [151 -56 ] (18,26). The process can be adjusted to vary the amount of branching (see Imines, cyclic). Polyamines are considerably lower in molecular weight compared to acrylamide polymers, and therefore their solution viscosities are much lower. They are sold commercially as viscous solutions containing 1—20% polymer, and also any by-product salts from the polymerization reaction. The charge on polyamines depends on the pH of the medium. They can be quaternized to make their charge independent of pH (18). 

Chlorinated C2> Perchloroethylene (PCE) and trichloroethylene (TCE) can be produced either separately or as a mixture in varying proportions by reaction of C2-chlorinated hydrocarbons, eg, C2-chlorinated waste streams or ethylene dichloride, with a mixture of oxygen and chlorine or HCl. 

Chemical Processing Intermediates and Other Applications. Monoethanolamine can be used as a raw material to produce ethylenedianiine. This technology has some advantages over the ethylene dichloride process in that salts are not a by-product. Additional reactions are requked to produce the higher ethyleneamines that are normally produced in the ethylene dichloride process. 

Ethylene Dichloride Pyrolysis to Vinyl Chloride. Thermal pyrolysis or cracking of EDC to vinyl chloride and HCl occurs as a homogenous, first-order, free-radical chain reaction. The accepted general mechanism involves the four steps shown in equations 10—13 ... 

Chlorination of Ethylene Dichloride. Tetrachloroethylene and trichloroethylene can be produced by the noncatalytic chlorination of ethylene dichloride [107-06-2] (EDC) or other two-carbon (C2) chlorinated hydrocarbons. This process is advantageous when there is a feedstock source of mixed C2 chlorinated hydrocarbons from other processes and an outlet for the by-product HCl stream. Product ratios of tri- and tetrachloroethylene are controlled by adjusting the CI2 type="subscript">2 EDC ratio to the reactor. Partially chlorinated by-products are recycled to the chlorinator. The primary reactions are... 

Noncatalytic ring chlorination of toluene in a variety of solvents has been reported. Isomer distributions vary from approximately 60% ortho in hydroxyhc solvents, eg, acetic acid, to 60% para in solvents, eg, nitromethane, acetonittile, and ethylene dichloride (49,50). Reaction rates are relatively slow and these systems are particularly appropriate for kinetic studies. 

The polymerization iavolves the reaction of sodium polysulftde with ethylene dichloride ia aqueous media at 70°C for 2—6 h, yielding an aqueous dispersion (latex) of the polysulftde mbber. 

Addition. Addition reactions of ethylene have considerable importance and lead to the production of ethylene dichloride, ethylene dibromide, and ethyl chloride by halogenation—hydrohalogenation ethylbenzene, ethyltoluene, and aluminum alkyls by alkylation a-olefms by oligomerization ethanol by hydration and propionaldehyde by hydroformylation. 

In order to assure control of the reaction, the vapor-phase inhibitor concentration must be closely controlled in the ppm range. Although several compounds have been claimed to be useful, it is likely that commercial processes use only ethylene dichloride or some of the simpler chlorinated aromatics (102). In general, the choice between inhibitors is not based on their differences in performance, but rather on the designers preference for dealing with the type of control problems each inhibitor system imposes (102). 

Cataljdic reactions performed in fluid beds are not too numerous. Among these are the oxidation of o-xylene to phthalic anhydride, the Deacon process for oxidizing HCl to CI2, producing acrylonitrile from propylene and ammonia in an oxidation, and the ethylene dichloride process. In the petroleum industry, cataljdic cracking and catalyst regeneration is done in fluid beds as well as some hydroforming reactions. 

In 1928 J. C. Patrick attempted to produce ethylene glycol by reacting ethylene dichloride with sodium polysulphide. In fact a rubbery polymer was formed by the reaction ... 

The chemistry of side reactions and by-products may also offer opportunities for increasing the inherent safety of a process. For example, a process involving a caustic hydrolysis step uses ethylene dichloride (EDC 1,2-dichloroethane) as a solvent. Under the reaction conditions a side reaction between sodium hydroxide and EDC produces small but hazardous quantities of vinyl chloride ... 

The importance of the solvent, in many cases an excess of the quatemizing reagent, in the formation of heterocyclic salts was recognized early. The function of dielectric constants and other more detailed influences on quatemization are dealt with in Section VI, but a consideration of the subject from a preparative standpoint is presented here. Methanol and ethanol are used frequently as solvents, and acetone,chloroform, acetonitrile, nitrobenzene, and dimethyl-formamide have been used successfully. The last two solvents were among those considered by Coleman and Fuoss in their search for a suitable solvent for kinetic experiments both solvents gave rise to side reactions when used for the reaction of pyridine with i-butyl bromide. Their observation with nitrobenzene is unexpected, and no other workers have reported difficulties. However, tetramethylene sulfone, 2,4-dimethylsulfolane, ethylene and propylene carbonates, and salicylaldehyde were satisfactory, giving relatively rapid reactions and clean products. Ethylene dichloride, used quite frequently for Friedel-Crafts reactions, would be expected to be a useful solvent but has only recently been used for quatemization reactions. ... 

Five hundred milligrams of the diacetate of (dl)-reg.-1-p-nitrophenyl-2-dichloroacetamido-propane-1,3-diol is dissolved in a mixture consisting of 25 cc of acetone and an equal volume of 0.2 N sodium hydroxide solution at 0°C and the mixture allowed to stand for one hour. The reaction mixture is neutralized with hydrochloric acid and evaporated under reduced pressure to dryness. The residue is extracted with several portions of hot ethylene dichloride, the extracts concentrated and then cooled to obtain the crystalline (dl)-reg.-l-p-nitrophenyl-2-dichloroacetamidopropane-1,3-diol MP 171°C. 

The second step is the dehydrochlorination of ethylene dichloride (EDC) to vinyl chloride and HCl. The pyrolysis reaction occurs at approximately 500°C and 25 atmospheres in the presence of pumice on charcoal ... 

Important applications for titanium have been developed in processes involving acetic acid, malic acid, amines, urea, terephthalic acid, vinyl acetate, and ethylene dichloride. Some of these represent large scale use of the material in the form of pipework, heat exchangers, pumps, valves, and vessels of solid, loose lined, or explosion clad construction. In many of these the requirement for titanium is because of corrosion problems arising from the organic chemicals in the process, the use of seawater or polluted cooling waters, or from complex aggressive catalysts in the reaction. 

Reaction of chlorine with ethylene to produce ethylene dichloride (EDC). 

Reactions in various alkyl halide solvents. A preliminary survey of polymerisations catalysed by titanium tetrachloride in various alkyl halide solvents was undertaken using highly purified materials and a vacuum technique. The most important qualitative result obtained was that in the solvents methylene dichloride, ethyl chloride, ethylene dichloride,... 

The most thoroughly studied system is styrene-perchloric acid in methylene and ethylene dichloride over the temperature range -90 °C to +30 °C. Most of the facts about this reaction are not in dispute and the essential features are these [25-32] ... 

We report spectroscopic and conductimetric studies on the reactions of styrene in the presence of perchloric acid (most in methylene dichloride but some in ethylene dichloride), both during and after the polymerisation. During polymerisation no ions are detectable, but at the end aralkyl (and subsequently allylic) ions are formed. Quantitative results show that ion formation sets in when the styrene concentration has fallen to four times the acid concentration we interpret this finding as showing that the ester (oligo-)styryl perchlorate requires four molecules of styrene for stabilisation in solution. 

The original rnanufacturing route to vinyl chloride (VC) didn t involve ethylene dichloride (EDC) but was the reaction of acetylene with hydrochloric acid. This process was commercialized in the 1940s, but like most acetylene-based chemistry in the United States, it gave way to ethylene in the 1950s and 1960s. The highly reactive acetylene molecule was more sensitive, hazardous,... 

Thus hydrochloric acid is a derivative of chlorine. About 93% of it is made by various reactions including the cracking of ethylene dichloride and tetrachloroethane, the chlorination of toluene, fluorocarbons, and methane, and the production of linear alkylbenzenes. It is also a by-product of the reaction of phosgene and amines to form isocyanates. 

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