Anhydrous hydrogen chloride gas

Pure anhydrous hydrogen chloride gas is made in much smaller amounts by combining chlorine and hydrogen directly. 

Anhydrous hydrogen chloride gas is used to produce phosphonium chloride, PH4CI, which is a flame retardant for cotton textiles. Other major apphcations include manufacture of a number of high purity metal chlorides, ammonium chloride, chlorosulfuric acid recovery of waste metals preparation of alkyl chlorides and chloroacetic acids and as a chlorinating agent in organic syntheses. 

Anhydrous hydrogen chloride gas purchased from Burnox, Kansas City, MO. was employed. 

Method 1 Preparation of Anhydrous Hydrogen Chloride gas from pickling salt (sodium... 

Figure 038. Set-up for the preparation of anhydrous hydrogen chloride gas. Note gently heating the reaction flask can help...

Anhydrous hydrogen chloride gas was bubbled into a solution consisting of the product from Step 2 (7.88 mmol) dissolved in 150 ml diethyl ether for 15 minutes. Thereafter the mixture stirred an addition 15 minutes at 0-5 °C and was filtered. The solid was re-crystallized in methyl alcohol/diethyl ether, 1 1, and the product isolated in 74.9% yield, mp = 258-259°C. IR and H- and C-NMR data supplied. 

The ketones were converted to the E,Z-alkyl aryl methanone oximes by a variety of methods. Most commonly, the ketone and hydroxylamine hydrochloride were suspended in ethanol and two equivalents of pyridine added. After isolation, the oximes were treated with anhydrous hydrogen chloride gas to give the hydrogen chloride salt of the -alkyl aryl methanone oxime(101. The resulting salt was treated with dilute sodium bicarbonate to yield the desired E-alkyl aryl methanone oxime. Earlier literature reports indicated that E-aldoxime was converted to the Z-aldoxime under similar conditions(11). 

Anhydrous hydrogen chloride gas can be generated by adding drop-wise concentrated sulfuric acid (80 mL) to NaCl (100 g). 

A slow flow of anhydrous hydrogen chloride gas is now introduced through the capillary tube E. This hydrogen chloride addition should continue throughout the electrolysis to maintain a saturated solution. A trickle of water is allowed to drip into the porous cup. The rate of water addition determines the voltage requirement of the electrolytic cell. Thus, changes in the rate may be required during the electrolysis, but a convenient initial rate of addition is about 4 1./24 hr. 

A second crop is a also collected from the ensuing filtrate. This product is dissolved in 200 ml chloroform and treated with an excess of anhydrous hydrogen chloride (gas). The precipitate thus obtained is collected and dried at 50°C (in vacuo). It is the penultimate intermediate called 4-methyl-2 -(pam-chlorophenoxy-l-piperazine carhoxanilide hydrochloride (II) having mp 210-213 C. 

Reactions with very large chemical equilibrium constants (e.g., > 10,000) at reactor conditions of temperature and pressure provide an opportunity for approaching 100% conversion during a single pass through the reactor. In addition, when the feed contains stoichiometric proportions of the reactants with no impurities and the reaction leads to only one product, then in principle no separation section is needed. One such situation exists. It is the manufacture of anhydrous hydrogen chloride gas from pure, evaporated chlorine and a stoichiometric amount of pure, electrolytic hydrogen by the reaction ... 

FIGURE MI. Heat capacity of anhydrous hydrogen chloride gas. 

Reagent grade hydrochloric acid contains up to O.03 ppm of lead (S5). Solution of anhydrous hydrogen chloride gas In purified water Is the usual method of obtaining the pure acid (C0). Scrubbing the gas twice In a bubble tower with triply distilled water before dissolution reduces the lead concentration to O.06 ppb (t6). Very pure hydrochloric acid can also be obtained by Isothermal distillation, e.g., by placing a dish of concentrated hydrochloric acid and a dish of pure water (in platinum, silica, or polyethylene) side by side In an empty desiccator and allowing to stand for a day or so (S5). 

Tantalum is resistant to anhydrous hydrogen chloride gas to at least 250°C. 

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