Ethylene hydrochlorination

A highly economical production of ethyl chloride combines radical ethane chlorination and ethylene hydrochlorination.185 186 Called the Shell integrated process, it uses the hydrogen chloride produced in the first reaction to carry out the second addition step ... 

Values of Lcooi (by the exan le of ethylene hydrochlorination) and R for various number of tubes providing at given productivity of shell-and-tube reactor the temperature about 273 K in reaction zone at two values of Tc (238K and 258K) are presented in Table 4.2. 

Dependence of cooling zone length Lcooi (Tr = 273 K) on tubes number N and radius Rn in shell-and-tube reactor under ethylene hydrochlorination (conditions as in Table 4.1, V = 1 m/sec,... 

Figure 4.11. Dependence of cooling zone length Lcooi and heat emission coefficient a on hydrodynamic regime of tubular apparatus work for water (0) (heat exchange) and chlorethyl ( ) (heat exchange under proceeding of chemical reaction of liquid-phase ethylene hydrochlorination) at fixed productivity (10,34 mVh). (Tad = 374 K To = 278 K Tr = 293 K Tc = 283 K).

Table 2.5 demonstrates the dependence of the cooling zone length which provides 0 °C (273 K) in a reaction zone at a given output and the values (-35 °C (238 K) and 258 °C (531 K)), on the radius R (the ethylene hydrochlorination process is given as an example) for various numbers of tubes in a shell-and-tube turbulent reactor. 

Table 2.5 The dependence of cooling length zone (Tp = 0 on the number of tubes N and radius R in3L shell-and-tube turbulent reactor for the ethylene hydrochlorination process (AP = 322.5 kg/m, q = 552 kilojoules/ kg, k = 10 1/mol-s, y = 1 m/s, Tq = -10 and AT = 100 C) ...

Characteristic examples of industrial fast chemical reactions are the electrophilic polymerisation of isobutylene [7], its copolymerisation with isoprene [10], chlorination of olefins [17] and butyl rubber [18], ethylene hydrochlorination [17], sulfation of olefins [19], neutralisation of acidic and basic media [20], isobutene alkylation (production of benzines) [21-23], and so on. These examples of fast liquid-phase reactions and a variety of such processes assume a formal approach for their calculation and modelling, based on material and heat balance in the industrial implementation of respective products. It is a priori acknowledged that is not difficult to achieve an isothermic mode for fast chemical exothermic processes if you are aware of the process behaviour and can control it. 

Ethyl Chloride. Most ethyl chloride [75-00-3] is produced by the hydrochlorination of ethylene (qv) using anhydrous HCl. Historically, the primary use of ethyl chloride was for the manufacture of tetraethyllead (TEL), a primary component of antiknock mixes in gasolines. Use has declined as a... 

Three industrial processes have been used for the production of ethyl chloride hydrochlorination of ethylene, reaction of hydrochloric acid with ethanol, and chlorination of ethane. Hydrochlorination of ethylene is used to manufacture most of the ethyl chloride produced in the United States. Because of its prohibitive cost, the ethanol route to ethyl chloride has not been used commercially in the United States since about 1972. Thermal chlorination of ethane has the disadvantage of producing undesired by-products, and has not been used commercially since about 1975. 

Hydrochlorination of Ethylene. The exothermic vapor-phase reaction between ethylene [74-85-1] and hydrogen chloride [7647-01-0] can be carried out at 130—250°C under a variety of catalytic conditions. Yields are reported to be greater than 90% of theoretical (14). 

Significant quantities of ethyl chloride are also produced as a by-product of the catalytic hydrochlorination over a copper chloride catalyst, of ethylene and hydrogen chloride to produce 1,2-dichloroethane, which is used as feedstock in the manufacture of vinyl choride (see Vinyl polymers). This ethyl chloride can be recovered for sale or it can be concentrated and catalyticaHy cracked back to ethylene and hydrogen chloride (25). As the market for ethyl chloride declines, recovery as an intermediate by-product of vinyl chloride manufacture may become a predominant method of manufacture of ethyl chloride. 

Halogenation and dehalogenation are catalyzed by substances that exist in more than one valence state and are able to donate and accept halogens freely. Silver and copper hahdes are used for gas-phase reactions, and ferric chloride commonly for hquid phase. Hydrochlorination (the absoration of HCl) is promoted by BiCb or SbCl3 and hydrofluorination by sodium fluoride or chromia catalysts that form fluorides under reaction conditions. Mercuric chloride promotes addition of HCl to acetylene to make vinyl chloride. Oxychlori-nation in the Stauffer process for vinyl chloride from ethylene is catalyzed by CuCL with some KCl to retard its vaporization. 

By-product HCl may be used for the hydrochlorination of ethylene to produce more ethyl chloride. Hydrochlorination of ethylene, however, is the main route for the production of ethyl chloride ... 

Chloroethane is produced by the hydrochlorination of ethylene. It is used in the manufacture of tetraethyllead, as an industrial ethylating agent, as a blowing agent in the production of polystyrene foam and as a local anaesthetic. Occupational exposure occurs during the production of tetraethyllead, and industrial emissions have led to detectable levels of chloroethane in ambient air (lARC, 1991). 

Ethyl Chloride. Hydrochlorination of ethylene with HC1 is carried out in either the vapor or the liquid phase, in the presence of a catalyst.182-184 Ethyl chloride or 1,2-dichloroethane containing less than 1% A1C13 is the reaction medium in the liquid-phase process operating under mild conditions (30-90°C, 3-5 atm). In new plants supported AlClj or ZnCl2 is used in the vapor phase. Equimolar amounts of the dry reagents are reacted in a fluidized- or fixed-bed reactor at elevated temperature and pressure (250-400°C, 5-15 atm). Both processes provide ethyl chloride with high (98-99%) selectivity. 

Ethylchloride. At present the main industrial technique to produce ethylchloride is the hydrochlorination of ethylene. 

Finally, ethylchloride can be obtained by a combined technique from a mixture of ethane and ethylene. The process is based on combined subsequent reactions of substitutuve chlorination of ethane and hydrochlorination of ethylene with hydrogen chloride obtained from the first reaction ... 

Ethyl Chloride. Most of the ethyl chloride is made by the exothermic hydrochlorination of ethylene, in either the liquid or the vapor phase Ain... 

Direct chlorination of vinyl chloride generates 1,1,2-tnchloroethane [79-00-5] from which vinylidene chloride required for vinylidene polymers is produced. Hydrochlorination of vinylidene chloride produces 1,1,1-trichloroethane [71-55-6], which is a commercially important solvent. Trichloroethylene and perchloroethylene are manufactured by chlorination, hydrochlorination, or oxychlorination reactions involving ethylene. Aromatic solvents or pesticides such as monochlorobenzene, dichlorobenzene, and hexachlorobenzene are produced by reaction of chlorine with benzene. Monochlorobenzene is an intermediate in the manufacture of phenol, insecticide DDT, aniline, and dyes (see Chlorocarbons a>td Chlorohydrocarbons.)... 

Vinyl chloride is produced in the following industrial reactions (1) the thermal cracking of 1,2-dichlor-oethane, which is produced by the chlorination and/ or oxychlorination of ethylene and (2) the hydrochlorination of acetylene. The vast majority of vinyl chloride is used for the production of polyvinyl chloride (PVC) and the manufacture of copolymers with monomers such as vinyl acetate or vinylidene chloride. A much smaller proportion of vinyl chloride is used in the production of chlorinated solvents - primarily trichloroethanes. 

The process is fed with three streams ethane, ethylene, and chlorine. The ethane and ethylene streams have the same molar flow rate, and the ratio of chlorine to ethane plus ethylene is 1.5. The ethane/ethylene stream also contains 1.5 percent acetylene and carbon dioxide. (For this problem, just use 1.5 percent carbon dioxide.) The feed streams are mixed with an ethylene recycle stream and go to the first reactor (chlorination reactor) where the ethane reacts with chlorine with a 95 percent conversion per pass. The product stream is cooled and ethyl chloride is condensed and separated. Assume that all the ethane and ethyl chloride go out in the condensate stream. The gases go to another reactor (hydrochlorination reactor) where the reaction with ethylene takes place with a 50 percent conversion per pass. The product stream is cooled to condense the ethyl chloride, and the gases (predominately ethylene and chlorine) are recycled. A purge or bleed stream takes off a fraction of the recycle stream (use 1 percent). Complete the mass balance for this process. 

Air oxidation of a variety of aliphatic and alkyl aromatic compounda air oxidation of p-nitrotoluene sulfuric acid substitution chlorination of a variety of organic compounds reaction between isobutylene and acetic acid oxidation of ethylene to acetaldehyde (Wacker processes) hydrochlorination of olehns absorption of phosphine in an aqueous soluhon of formaldehyde and hydrochloric acid acehc acid from the carbonylation of methanol oxidation of tri-alkyl phosphine dimerization of olefins. 

As in steam cracking, a large number of by-products is produced. Some of them result from the consecutive reactions of the chlorination of vinyl chloride and of its derivatives obtained by dehydrochlorination (tri-, tetra-, pentachloroethane, perchloro-ethane, di-, trichloroethylene. perchloroethyleneX and the others from the hydrochlorination of vinyl chloride il.l-dichloroethane), while others result from decomposition reactions (acetylene, cokei or conversion of impurities initially present (hydrocarbons such as ethylene, butadiene and benzene, chlorinated derivatives such as chloroprene, methyl and ethyl Chlorides, chloroform, carbon tetrachloride, eta, and hydrogen) ... 

Cracking of preheated ethylene dichloride, at between 450 and 550°C. at 13.10 Pa absolute, followed by quenching, first indirectly for the production of steam, and then directly by the in-line injection of cold product, and then by the separation by distillation of the hydrochloric arid co-produced, which is recycled to the acetylene hydrochlorination stage. 

Hydrochlorination-Dehydrochlorinatiom Activation energies have never been measured or calculated for the simplest reactions of this type involving ethylene and ethyl chloride. However, Sherman, Quimby, and Sutherland have calculated activation energies for the following reactions ... 

Figure 9-3. Technological scheme of production of the vinyl chloride monomer (1) plasma-chemical pyrolysis (2) cleaning from higher unsaturated hydrocarbons (3) hydrochlorination of acetylene (4) chlorination of ethylene (5) thermal pyrolysis of dichloroethane.

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