Inorganic chlorides

A convenient synthesis of organochlorosilanes from organosilanes is achieved by reaction with inorganic chlorides of Hg, Pt, V, Cr, Mo, Pd, Se, Bi, Fe, Sn, Cu, and even C. The last compounds, tin tetrachloride, copper(II) chloride, and, under catalytic conditions, carbon tetrachloride (117,118), are most widely used. 

When heated with pyrocatechol [720-80-9] copper powder, and alcohoHc sodium hydroxide, carbon tetrachloride gives a blue color that changes to red on addition of hydrochloric acid. This color reaction is not produced by chloroform. Quantitative analysis of carbon tetrachloride may be done by first decomposing the sample free of organic and inorganic chlorides, heating in a sealed tube with alcohoHc potash, and subsequently determining the potassium chloride formed as the silver haHde. The Zeiss interference refractometer has been used to determine the concentration of carbon tetrachloride vapor in air (36). 

Materials of Construction. GeneraHy, carbon steel is satisfactory as a material of construction when handling propylene, chlorine, HCl, and chlorinated hydrocarbons at low temperatures (below 100°C) in the absence of water. Nickel-based aHoys are chiefly used in the reaction area where resistance to chlorine and HCl at elevated temperatures is required (39). Elastomer-lined equipment, usuaHy PTFE or Kynar, is typicaHy used when water and HCl or chlorine are present together, such as adsorption of HCl in water, since corrosion of most metals is excessive. Stainless steels are to be avoided in locations exposed to inorganic chlorides, as stainless steels can be subject to chloride stress-corrosion cracking. Contact with aluminum should be avoided under aH circumstances because of potential undesirable reactivity problems. 

Inorganic Chlorides/Halides — These metallic salts are formed from the reaction of a weak base with the strong acid HCl. Salts such as these dissolve in water to produce a markedly acidic solution. This is exemplified by aluminum chloride, which is corrosive due to the acidity resulting from the hydrolysis that produces aluminum and chlorine ions. Anhydrous AICI3 hydrolyzes violently when contacted by water. 

NMR studies on graphite-phosphoric acid showed simultaneous, motional narrowing of both H and resonances above 225 K, indicating high mobility of phosphoric acid in the compound (FS). Chloro-sulfonic acid is inserted alone into graphite in the presence of many inorganic chlorides. The reaction temperature and stage seem to be related to the redox potential of the M"+-M couple (M3). 

The pyrolysis produets obtained from a variety of mixed plasties eontaining PVC are investigated. While hydroehlorie aeid is the major chlorinated product produced by PVC pyrolysis, other chlorinated hydroearbons are produced. However, the composition and yield of these compounds are very much dependent upon the other polymers present in the plastic mixture. In the ease of a polymeric waste stream containing inorganic fillers, sueh as ealcium carbonate, the HCl produced by the PVC ean be neutralised in situ, leading to the produetion of inorganic chlorides, alleviating many of the concerns associated with HCl formation. 9 refs. 

Sodium, K, Ca, Mg, Zn and Fe and inorganic chlorides are the most widely occurring contaminants in solvent dyes for engineering thermoplastics such as PC, and need to be contained to within 250 ppm (specification ICP verification for QC purposes) [202]. 

In one procedure that has been widely used, the sample, after suitable treatment, is refluxed with sodium and isopropyl alcohol, after which the solution is diluted with water and the inorganic chloride is determined by standard methods (13, 54) The method has been adopted by the Association of Official Agricultural Chemists 29, 30) as a tentative one for technical DDT and for dusts, oil solutions, and aqueous emulsions of DDT, for use in the absence of other chlorine-containing compounds. The National Association of Insecticide and Disinfectant Manufacturers has also accepted the total-chlorine method for the analysis of these preparations 28). Essentially the same procedures have been described by Donovan 22), of the Insecticide Division of the Production and Marketing Administration, for technical DDT and various commercial DDT products containing no other compounds interfering with the chlorine determination. 

Table 11 Chlorination of iV-Oxides with Inorganic Chlorides ...

Note these data also indicated a preference for DS over the competing chloride concentration of between 30 and 60. This implies the dodecylsulfonate was accumulated in the diffuse double layer surrounding the alumina relative to its bulk solution concentration more than an order of magnitude more preferentially than the inorganic chloride adsorbate. As a consequence, it is perhaps not surprising that Fuerstenau and Wakamatsu (1975) observed the accumulation of hemimicelles on the alumina at only about 400 /jM (pH 7.2) and about 7 fjM (pH 5.2) bulk DS-concentrations (see discussion of hemimicelles). 

The monochloride is also employed in the manufacture of carbon tetrachloride and certain anhydrous inorganic chlorides. Its use has also been suggested in the refining of sugar. 

During combustion of the coal, organic chlorides are decomposed and liberate the chlorine atom as hydrochloric acid, while inorganic chlorides decompose with evolution of hydrochloric acid and ultimately leave a residue of the metallic oxide. Since approximately half the chlorine in coal occurs as inorganic chloride and the remainder as inorganic chloride, a correction for the chlorine present originally as inorganic material is easily applied when the total chlorine is known. 

This is generally believed to result from the substitution of chloride ions into the surface oxide lattice with subsequent breakdown of the passification of the underlying alloy. The elimination of inorganic chloride contamination from stainless steel components used in nuclear applications has been a goal of designers for many years. 

The peroxyl radical hydrolyzes in Eqs. (42)-(44). The products are inorganic chloride and formic acid. 

Reductive dechlorination also produces inorganic chloride ion, but glyoxylic acid [Eq. (63)] rather than formic acid. As with the halomethanes, peroxyl radical formation is an important intermediate. Oxygen is clearly important to achieving dechlorination in aqueous solution. 

Postirradiation chloride analyses indicated complete recovery of solute chlorine as inorganic chloride ion. 

The most influential parameter on the reaction products is the reaction temperature. Under subcritical conditions only a hydrolytic separation of 80 % (y-HCH) respectively 60 % (HCB) of the chlorine atoms was detected. In supercritical water the decomposition of the organic attached chlorine in y-HCH and HCB into inorganic chloride amounts more than 99 % Cl at 500 °C. In parallel there is a considerable decomposition of the hydrocarbon framework mainly to water soluble hydrocarbons and to gaseous products like carbon dioxide. SCWO conditions leads to a completely decomposition of theese compounds into environmental friendly reaction products without the formation of Cl2, HCl and dioxines. 

When inorganic chlorides (e.g., ammonium chloride) and organic chlorides collect (usually in the tops of columns and equipment connected to the tops of columns), mild to severe corrosion occurs. When organic nitrogen compounds in the feed exceed 0.05 wt% (500 ppm), cyanides and ammonia form. These compounds collect in the aqueous phases and cause corrosion of certain materials. The corrosion problems in the aqueous phases are discussed in the following section on overhead systems, in the Chapter Two section on characteristics of sour water, and in the Chapter Three section on coolers. 

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