Chlorine reaction system

Fig. 6. Schematic of the chlorine reaction system in the stratosphere with an ov view of the exchange times among the various subgroups of reactants.

From Allyl Alcohol. The reaction of allyl alcohol [107-18-6] with chlorine and water gives a mixture of glycerol m on ochl orohydrin s consisting of 73% 3-chloropropane-l,2-diol and 27% of 2-chloropropane-l,3-diol (57). In a recycle reaction system in which allyl alcohol is fed as a 4.5—5.5 wt % solution, chlorine is added at a rate of 7—9 moles per hour. The reaction time is about five seconds, the reaction temperature 50—60°C and the recycle ratio is 10—20 1. Under these conditions m on ochl orohydrin s have been obtained in 88% yield with 9% dichlorohydrins (58) (see Allyl ALCOHOL AND DERIVATIVES). 

A halogenating system related to the preceding case is formed by the reaction of triphenylphosphine with molecular bromine or chlorine. The system is not as sensitive to moisture as the phosphine-carbon tetrahalide system (see preceding section), but it suffers from the disadvantage that hydrohalic acids are produced as the reaction proceeds. Nevertheless, sensitive compounds can be successfully halogenated by the system, as exemplified by the preparation of cinnamyl bromide from the alcohol. 

Figure 3.8 shows a variety of materials. This, of course, is not surprising. In principle, the composition of a solid material will depend on several factors, including the reaction conditions. For example, when an oxidation is carried out a metal like Co will be in the metallic state or the oxidized. state depending on the reaction conditions. When used in chlorination many systems will be present as chlorides. 

The ACTIV-OX system has been developed to meet the needs for a safe and controllable chlorine dioxide system for application in small water using systems. The system instantaneously delivers over 90% of the available chlorine dioxide at a pH of 4 compared to other systems which require lower pH and or longer reaction times (Fig 1 and 2). 

The most straightforward way to operate such a process is to maintain a constant chlorine addition rate and a constant temperature. However, both the constant value of the chlorine addition rate and the fixed temperature should be optimized. The temperature of the reaction system is allowed to vary within the set temperature range, but kept constant throughout a batch cycle. The batch time is divided into twenty time... 

Reducing waste by upgrading waste byproducts. Waste byproducts can sometimes be upgraded to useful materials by subjecting them to further reaction in a different reaction system. An example was quoted in Chapter 13 in which hydrogen chloride, which is a waste byproduct of chlorination reactions, can be upgraded to chlorine and then recycled to a chlorination reactor. 

Consider the following chlorination of benzene reaction system of elementary reactions. 

Rapid addition of bromine to the dried solvent to make a 10% solution caused a vigorous reaction with gas evolution. As this happened in a newly installed brightly illuminated fume cupboard lined with a reflective white finish, photocatalysed bromination of the solvent may have been involved, as has been observed in chlorine-ether systems. 

Heat recovery system (HRS), 23 190 energy demand in, 23 190-192 grid representation of, 23 188-189 Heat recovery system process, 23 786-787 Heat release calorimeters, 22 458 Heat removal, from direct HDC chlorination reaction, 25 638 Heat resistance... 

The same phenomenon, i.e. that the secondary a-deuterium KIE is determined by the changes in only the shorter reacting bond in the SN2 transition state rather than by the nucleophile-leaving group distance, has been found in a completely different reaction system. Matsson, Westaway and co-workers (Matsson et al., 1996) used ku/k14 carbon incoming nucleophile, chlorine leaving group (Hill and Fry, 1962), and ku/ku a-carbon (Fry, 1970) KIEs to model the transition states for a series of SN2 reactions between p-substituted benzyl chlorides and labelled cyanide ion (reaction (17)). 

In a hood, through a rapidly stirred suspension of 76 gm (0.396 mole) of cyclohexanoneazine in 300 ml of petroleum ether (b.p. 60°-90°C) cooled to —60°C is passed a slow stream of gaseous chlorine until a slight excess of the gas is noted. The excess of chlorine is removed by ventilation at the water aspirator. Then the solution is concentrated to half-volume by gentle evaporation at reduced pressure. The reaction system is filtered free from tarry impurities and the filtrate is allowed to stand for 24 hr at room temperature. The product gradually separates out and is isolated by filtration. Evaporation of the mother liquor may afford another crop of product. The total yield is 81.5 gm (78 %). The product, after recrystallization from petroleum ether, has a melting point of 66°C. (NOTE Since aliphatic azo compounds are inherently unstable and may serve as free radical sources, the stability of the product should always be checked with due precautions, and excessive exposure to heat should always be avoided.)... 

The presence of chlorine radical chain reactions in a photocatalytic reaction system may significantly increase reaction rates and photocatalytic efficiencies. These enhancements would appear to have the potential to overcome the shortcomings typically associated with the photocatalytic oxidation of aromatic contaminants if a chlorine radical chain reaction could be initiated in conjunction with an aromatic photocatalytic reaction and if the chlorine radicals were capable of reacting with (and thus accelerating the conversion of) the aromatic contaminant of interest. Two potential configurations for combining chlorine radical promotion with the photocatalytic oxidation of aromatic contaminants have been examined in some detail mixed contaminant feeds and prechlorinated catalysts. 

The Hydrogen-Chlorine System The formation of hydrochloric acid from hydrogen and chlorine is a well-known gas-phase reaction. This simple reaction system serves to illustrate the important steps that are characteristic of a chain reaction. The overall reaction can be written as... 

These data were obtained by the checkers. The submitters report conversion of 76-80% after only 9 hr. It seems likely that the rate of the reaction may be sensitive to the dimensions and mechanical features of the chlorine introduction system, and/or an induction period. It is easy and important to monitor the process. 

To illustrate the use of the algorithm, a case of allyl chloride manufacturing was used. Allyl chloride is manufactured by means of non-catalytic chlorination of propylene. Consider the following reaction system. 

A systematic ab initio investigation of the water-assisted decomposition of chloro-methanol, dichloromethanol, and formyl chloride as a function of the number of water molecules (up to six) building up the solvation shell has been reported.33 The decomposition reactions of the chlorinated methanols and formyl chloride are accelerated substantially as the reaction system involves additional explicit coordination of water molecules. 

Specific procedures for the synthesis of M0CI4, MoCl, and M0CI2 are described in the sections that follow. Other methods of synthesis are also summarized in these sections. Procedures for the synthesis of M0CI5 have been given in Inorganic Syntheses 7, 167 (1963) and 9, 135 (1967). The industrial method is the direct chlorination of metal and is recommended in some laboratories.12-18 A convenient laboratory technique is the liquid-phase reaction system that uses refluxing thionyl chloride and molybdenum (VI) oxide.14... 

Butyl chloride (BC) + Cl2 On being cooled to 77 K, a solution of Cl2 in BC (mole ratio 1 3) completely vitrifies (Tg 100 K). The irradiation of the system by 60Co y rays leads to the accumulation of stabilized active centers. The chain chlorination reaction, not observed during radiolysis, is initiated only on heating up the irradiated system, starting from the devitrification region. The heat of reaction is 138 + 12kJ/mole.27... 

The best-studied were two film systems the chlorination reaction in a solid solution of Cl2 in BC and the copolymerization reaction of sulfur dioxide with isoprene. Under the above-described conditions of cooling, the liquid films in both systems vitrified. 

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