Study of the interaction of hydrogen chloride and chlorine oxide
Hydrogen chloride, a by-product of the production of organic chlorine products (as well as a number of others), finds it difficult to find useful ways. The hydrochloric acid obtained from it, due to the presence of organic impurities in it, also finds very limited areas of realization. The optimal solution to the problem is the creation of chlorine-balanced processes in which the hydrogen chloride produced in the direct chlorination of the hydrocarbon is used here in the oxidative chlorination stage of the same feedstock to produce the same chlorinated products as in direct chlorination. In practice, the idea of creating a balanced process is realized only when obtaining vinyl chloride from ethylene. For other hydrocarbons (methane, benzene), the process is constrained by the much lower oxidative chlorination stage rates compared to direct chlorination. It is recognized that the limiting stage of oxychlorination is the Deacon process-the oxidation of hydrogen chloride to chlorine by oxygen on a catalyst whose main component is copper chloride. Numerous attempts to improve the catalyst by the reconsideration of metals and their compounds, as well as the modification of carriers for them, did not lead to a significant acceleration of the process. A much greater effect is observed when oxygen is replaced by more active oxidizers: nitrogen oxides, ozone, hydrogen peroxide, especially chlorine monoxide Cl2O. Since the interaction of chlorine monoxide with hydrogen chloride occurs almost instantaneously already at room temperature, it was necessary to create equipment and devices for their production, storage and dosing, as well as methods for analyzing starting materials and products. To study the kinetics of the process, a method of low-temperature infrared spectrophotometry was used that made it possible to directly monitor the rate of consumption of reagents and the accumulation of products, which required the development of a special design cuvette reactor that maintained the required low temperatures for a time sufficient to complete the reaction. According to the IR spectra data, the assumptions about the composition of the reaction products of the oxidation of hydrogen chloride with chlorine monoxide are made, as well as the probable mechanism of this reaction.