The study of direct electrolysis of water in the Vietnam Sea
in the production of sodium hypochlorite

Summary

Electrochemical sodium hypochlorite is used at water supply facilities all around the world. The use of natural waters containing chlorides as a raw material is very promising since it greatly simplifies the process flow scheme for producing sodium hypochlorite. Direct electrolysis technology can be retrofitted into the existing water treatment schemes without significant changes. The use of natural water containing chlorides eliminates the purchase of salt which reduces the cost of the finished product. The results of studies of direct electrolysis of water in the Vietnam Sea are presented. During the experiments the effect of seawater flow rate and current density on the concentration of active chlorine in the resulting sodium hypochlorite, the change in the current chlorine yield and the specific energy consumption per 1 kg of generated active chlorine were determined. The main process parameters are determined that provide for producing sodium hypochlorite by direct electrolysis of sea water using an iridium-ruthenium oxide titanium anode as electrodes. It was shown that the current chlorine yield reaches maximum values (85–90%) at an active chlorine concentration in the product of 2 ± 0.2 g/dm3 which motivate the technological and economic feasibility of obtaining sodium hypochlorite from sea (ocean) water.

Key words

sodium hypochlorite , chlorides , sea water , direct water electrolysis , current density

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