Methyl chloride disposal

Chlorinated by-products of ethylene oxychlorination typically include 1,1,2-trichloroethane chloral [75-87-6] (trichloroacetaldehyde) trichloroethylene [7901-6]-, 1,1-dichloroethane cis- and /n j -l,2-dichloroethylenes [156-59-2 and 156-60-5]-, 1,1-dichloroethylene [75-35-4] (vinyhdene chloride) 2-chloroethanol [107-07-3]-, ethyl chloride vinyl chloride mono-, di-, tri-, and tetrachloromethanes (methyl chloride [74-87-3], methylene chloride [75-09-2], chloroform, and carbon tetrachloride [56-23-5])-, and higher boiling compounds. The production of these compounds should be minimized to lower raw material costs, lessen the task of EDC purification, prevent fouling in the pyrolysis reactor, and minimize by-product handling and disposal. Of particular concern is chloral, because it polymerizes in the presence of strong acids. Chloral must be removed to prevent the formation of soflds which can foul and clog operating lines and controls (78). 

AH persons who have occasion to use or handle methyl chloride should be thoroughly instmcted and adequately supervised in the proper methods of handling the substance to prevent or minimize exposure to the Hquid or its vapors and in the proper methods of disposing of this chemical. 

Methyl chloride may be absorbed from leaking cylinders into a suitable organic solvent such as xylene, toluene, benzene, or chloroform after attachment of the appropriate regulator and flexible tubing. It may subsequently be recovered for use, or it may be disposed of in a manner suitable for disposal of a flammable gas and in accordance with federal, state or provincial, and local regulations [4]. 

Disposal of methyl chloride by, neutralizing, scrubbing, incineration, or by other means may be subject to permitting by federal, state or provincial regulations. Persons involved with disposal of methyl chloride should check with the environmental authorities having jurisdiction to determine the applicability of permitting regulations to disposal activities. 

Methyl chloride currently is produced by two methods by the reaction of hydrogen chloride and methanol and by the chlorination of methane. Methanol hydrochlorination has become increasingly important, whereas methane chlorination has declined as the route to produce only methyl chloride. The hydrochlorination process has the advantage that it utilizes, instead of generating, hydrogen chloride, a product whose disposal has become increasingly difficult. The reaction of methanol with excess hydrogen chloride is carried out in the gas phase at temperatures... 

Conjugate addition of methyl magnesium iodide in the presence of cuprous chloride to the enone (91) leads to the la-methyl product mesterolone (92) Although this is the thermodynamically unfavored axially disposed product, no possibility for isomerization exists in this case, since the ketone is once removed from this center. In an interesting synthesis of an oxa steroid, the enone (91) is first oxidized with lead tetraacetate the carbon at the 2 position is lost, affording the acid aldehyde. Reduction of this intermediate, also shown in the lactol form, with sodium borohydride affords the steroid lactone oxandrolone... 

The enhanced reactivity of the axial 5-hydroxyl group over that of the equatorial group on C-3 in methyl quinate towards acid chlorides in pyridine has been attributed147 to intramolecular hydrogenbonding of the former group to the syn-axially disposed oxygen atom on C-l. 

Excess benzyl bromide and triethylamine in the presence of tin(II)chloride catalyst were used [91] for partial benzylation of methyl a-L-rhamnopyranoside and its 4-O-benzyl ether. Complexation of tin(II)chloride with vicinal m-disposed hydroxyl groups permitted selective benzylation at the 3- and 2-positions. Methyl 3-O-benzyl-or 3,4-di-O-benzyl-a-L-rhamnopyranoside, respectively, could be prepared in good yield by this method. No benzylation took place when benzyl chloride was used instead of benzyl bromide, or when other solvents than ethyl acetate or acetonitrile were tested. 

O-benzylidene-D-erythrose.123 The 3-hydroxyl group in the former is well disposed for nucleophilic attack on the benzylic carbon atom, to give the cts-fused, 1,3-dioxolane ring. Similarly, Ballou124 found that 2,4-O-ethylidene-D-erythrose in methanolic hydrogen chloride affords methyl 2,3-0-ethylidene-/3-D-erythrofuranoside. 

Treatment of 1,2 5,6-di-O-isopropylidene-a-D-allofuranose with methanolic hydrogen chloride for 20 hours affords the methyl 2,3-0-isopropylidene- and 2,3 5,6-di-0-isopropylidene-/3-D-allofurano-sides 118 again, migration to a favorably disposed hydroxyl group occurs. Evans62 reported the rearrangement of methyl 4,6-0-iso-propylidene-a-D-altropyranoside to the 3,4-acetal in acetone-sulfuric acid. 

Light ends are removed by extractive distillation and heavy ends are removed as a side stream from the final acetaldehyde product distillation column. Dissolved gases and methyl and ethyl chlorides are removed in the light ends column and sent to the flare for disposal. Heavy ends consist mainly of crotonaldehyde which is removed as a side stream product. The residue from the bottom of the final distillation column is water containing acetic acid and various chlorinated acetaldehydes. This stream is sent to a biological water treatment unit for disposal. 

The effect of the substitution on the phenyl ring can be illustrated by considering two parallel effects (1) the steric obstacle created by both the chloride and the methyl groups, which hinder the approaching of an aldehyde to the metal-alkoxide bond when disposed in the ortho position and (2) the electrostatic interaction between the metal and the chloride, which may facilitate the approach of the aldehyde to the metal center, and hence the activity (Fig. 1). 

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