Hydrogen Chloride, HCI, and Hydrochloric Acid

Hydrogen chloride and its aqueous solution, hydrochloric acid [337], are two of the most important basic industrial chemicals. Very pure HCI gas is formed by the direct synthesis of the gaseous elements 

The reaction of concentrated sulfiiric acid with common salt or potassium chloride 5 produces sodium or potassium sulfate, and as a by-product, HCl. 

Huge quantities of HCl are obtained from the chlorination of organics by substitution 

The amount of hydrogen chloride produced as a by-product exceeds by far the demand of the market for hydrochloric acid. Therefore most producers in the chlorine consuming industry try to recirculate the HCl into the production process, as far as it is economically feasible, e.g. by the oxychlorination process in the vinyl chloride production 

The management of the hydrochloric acid streams plays a decisive role for the equilibrium of the chlorine balance of an economic region. It is estimated, that in Europe one third of the total chlorine demand is covered by HCl [338), see Chapter 14.8. 

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