Ferric chloride, catalyst

The problem with the fiowsheet shown in Fig. 10.5 is that the ferric chloride catalyst is carried from the reactor with the product. This is separated by washing. If a reactor design can be found that prevents the ferric chloride leaving the reactor, the effluent problems created by the washing and neutralization are avoided. Because the ferric chloride is nonvolatile, one way to do this would be to allow the heat of reaction to raise the reaction mixture to the boiling point and remove the product as a vapor, leaving the ferric chloride in the reactor. Unfortunately, if the reaction mixture is allowed to boil, there are two problems ... 

Benzene Chlorination. In this process, benzene is chlorinated at 38—60°C in the presence of ferric chloride catalyst. The chlorobenzene is hydrolyzed with caustic soda at 400°C and 2.56 kPa (260 atm) to form sodium phenate. The impure sodium phenate reacts with hydrochloric acid to release the phenol from the sodium salt. The yield of phenol is about 82 mol % to that of the theoretical value based on benzene. Plants employing this technology have been shut down for environmental and economic reasons. 

The problem with the flowsheet shown in Figure 28.5 is that the ferric chloride catalyst is carried from the reactor with the product. This is separated by washing. If a design of reactor can be found that prevents the ferric chloride leaving the reactor, the effluent problems created by the... 

CH3.CHCH2, col liq having a smell taste resembling chloroform, fr p -97.6°, bp 57.3°, flash p -8.5°, d 1.1601 at 30°, nD 1.41638 at 20°, Qcomb 267.4 kcal/mol at Cv expl limits in air 5.9 15.9% by vol less narcotic but more toxic than chloroform can be produced by reacting HC1 with vinyl chloride in the presence of Al, Ferric or Zn chloride catalyst, or by reacting HC1 with acetylene in the presence of mercuric-ferric chloride catalyst at RT (Refs 1 35 p 148)... 

Wester et al (Ref 24) patented an industrial method of preparation of diarylamine, and more particularly of DPhA. Essentially the process comprises heating aniline in an autoclave at pressures betw 100 and 200psi, in the presence of ferric chloride catalyst in an amount betw 0.3% to 8.0% by wc of the aniline used. Yields as high as 58.8% were reported after heating for only 8 hrs at l60psi... 

This process is shown schematically in Figure 7. The ethylene part of the feed reacts with chlorine in the liquid phase to produce 1,2-di-chloroethane (EDC) by a simple addition reaction, in the presence of a ferric chloride catalyst (9). Thermal dehydrochlorination, or cracking, of the intermediate EDC then produces the vinyl chloride monomer and by-product HC1 (1). Acetylene is still needed as the other part of the over-all feed, to react with this by-product HC1 and produce VCM as in the all-acetylene route. 

The mono- and poly-alkylated benzenes are treated using modifications of the above procedure. Monoalkylbenzenes are added to a preformed complex of acyl halides and aluminum chloride in carbon tetrachloride (Perrier modification). In this manner, the manipulation is easier, no tars are encountered, and the yields are improved (85-90%). The procedure shows no advantage, however, in the acylation of alkoxy- or chloro-aromatic compounds. The addition of benzoyl chloride to p-alkylbenzenes in the presence of aluminum chloride in cold carbon disulfide is a good procedure for making p-alkylbenzophenones (67-87%). The condensation of homologs of benzene with oxalyl chloride under similar conditions yields p,p -di alkylbenzophenones (30-55%). Polyalkylbenzenes have been acylated with acetic anhydride and aluminum chloride (2.1 1 molar ratio) in carbon disulfide in 54-80% yields. Ferric chloride catalyst has been used under similar conditions. Acetylation of p-cymene with acetyl chloride and aluminum chloride in carbon disulfide yields 2-methyl-5-isopropylaceto-phenone (55%). ... 

Chlorobenzene (CeHsCl), an important solvent and intermediate in the production of many other chemicals, is produced by bubblingchlorine gas through liquid benzene in the presence of ferric chloride catalyst. In an undesired side reaction, the product is further chlorinated to dichlorobenzene, and in a third reaction the dichlorobenzene is chlorinated to trichlorobenzene. 

Allenes are cleanly formed by addition of Grignard reagents to pro-pargyl chlorides with ferric chloride catalyst.1 1... 

Kydonieus and Sandler [10] reported that mercaptans, especially fluorinated mercaptans, can react with acrylyl chloride or methacrylyl chloride in the presence of ferric chloride catalyst using a methylene chloride solution to yield... 

Chlorination reactor and condenser. The direct chlorination operation in Figure 3.7 is replaced by a cylindrical reaction vessel, containing a rectifying section, and a condenser. A pool of liquid dichloroethane, with ferric chloride catalyst dissolved, fills the bottom of the vessel at 90°C and 1.5 atm. Ethylene is obtained commonly from large cylindrical vessels, where it is stored as a gas at an elevated pressure and room temperature, typically 1,000 psia and 70°F. Chlorine, which is stored commonly in the liquid phase, typically at 150 psia and 70°F, is evaporated carefully to remove the viscous liquid (taffy) that contaminates most... 

In Section 3.4, as the operations are inserted into alternative flowsheets to manufacture vinyl chloride, rules of thumb or heuristics are utilized. For example, when positioning the direct chlorination operation, it is assumed that because the reaction is nearly complete at 90°C, ethylene and chlorine can be fed in stoichiometric proportions. Furthermore, when positioning the pyrolysis operation, the temperature and pressure are set at 500°C and 26 atm to give a 60% conversion. These assumptions and specifications are based on many factors, not the least of which is experience in the manufacture of vinyl chloride and similar chemicals. In this case, a patent by the B.F. Goodrich Co. [British Patent 938,824 (October 9, 1963)] indicates the high conversion of ethylene and chlorine over a ferric chloride catalyst at 90°C and recommends the temperature and pressure levels of the pyrolysis reaction. The decision not to use ethylene in excess, to be sure of consuming all of the toxic chlorine, is based on the favorable conversions reported experimentally by chemists. In the distillation operations, the choice of the key components, the quality of the feed streams and the distillate products, and the pressure levels of the towers are also based on rules of thumb. In fact, heuristics like these and many others can be organized into an expert system, which can be utilized to synthesize sections of this and similar chemical processes. 

Aliphatic primary nitro compounds yield trisubstituted pyridines when treated with CO under pressure using a noble metal—ferric chloride catalyst system[ll5] ... 

Thorium metal powder has recently been produced in the U.K. - on a scale of at least 6 kg per batch by an all-chloride electrolytic route, and information is available upon which a large-scale process could be based. Thorium tetrachloride is first produced in situ in an inert melt composed of sodium chloride and potassium chloride in eutectic proportions. Thorium dioxide and carbon are reacted with gaseous chlorine under the surface of the melt at a temperature of about 800°C in the presence of a ferric chloride catalyst. The catalyst is added as iron powder or pyrite (FeSg) in quantity equal to about 4 per cent of the weight of thoria. The ferric chloride, once formed, behaves as a chlorine carrier in the melt, by virtue of its ready reduction to ferrous chloride and subsequent rechlorination back to ferric chloride in contact with chlorine, i.e. 

The carbon sometimes takes the form of a block of graphite which has a chlorine inlet tube down the middle and is shaped so as to act also as a chlorine distributor, as shown in the small scale chlorinator in Fig. 7.5. Alternatively, the carbon may be in more intimate admixture with the thoria, e.g. when produced by the calcination of a mixture of thoria and starch, followed by grinding. In this case, a reasonable chlorination rate is obtained in the absence of the ferric chloride catalyst, provided the temperature is raised to 900°C. This would probably be the preferred technique for large-scale operation since the removal of an iron catalyst before... 

Chlorine, with a ferric chloride catalyst, reacts similarly. 

Stereosequence length of Isotactic units in poly(propylene oxide) is determined by the catalyst system used. The stereosequence length of isotactic units in stereoregular poly(pro-pylene oxide) polymers may be characterized from their melting point and degree of crystallinity. The stereosequence length of isotactic units in poly(propylene oxide) from ferric chloride catalyst is considerably longer than those from other catalyst systems such as diethyl zinc-water and diethyl zinc-water-isopropylamine. 

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