The Chloralkali Industry

Hydrogen another by-product Is used to produce rocket fuel and for hydrogenation. These products are essential for human life which makes it clear that the chloral’s process is beneficial to people. The chloral’s Industry revolves around three main methods of production. Each method uses an electrolytic cell in which a current is run through brine (saturated NCAA), resulting in chemical reactions at the electrodes and separation of sodium and chlorine. The three cells that are used are the mercury cell, the diaphragm cell and the membrane cell.

Each of these processes differ In the methods of production and also differ in the way the half-reactions are isolated. All three of the cells have efferent environmental impacts; however, the risks associated with the mercury cell and diaphragm cell have led to the membrane cell being the most widely used. The membrane cell Is the most widely used cell and accounts for 52% of chlorine production across Europe because it consumes a low amount of energy, is relatively inexpensive and produces very pure sodium hydroxide.

The cell operates by separating the anode and the cathode with an ion-exchange membrane. Only sodium Ions and a little water pass through the membrane. In the process the concentrated salt solution (An* CLC-) Is pumped Into the section with the anode. Chlorine ions are oxidized to form CO. The positive sodium ions bond with the OH- 1 OFF gas is also produced at the cathode. The Noah has to be concentrated slightly but the amount of steam to do so is small.

The consumption of electric energy is the lowest of the three processes and the amount of steam needed for concentration of Noah is relatively small. The mercury cell is an older cell and its main advantage is producing very pure hydrogen and chlorine as well as producing a high concentration of Noah. In the mercury cell there is a liquid mercury cathode and sodium forms an amalgam with it. The amalgam reacts with the water in a separate reactor known as a decomposer where hydrogen gas and sodium hydroxide are produced.

The mercury cell uses a huge amount of electricity and the use of mercury can cause huge environmental problems because it is very poisonous and it is a bio- accumulative which means once it enters the food chain poisoning from mercury can get worse as it moves up the various atrophic levels. Accidents like the one at Inanimate at Japan affected people greatly and caused poisoning of people. The diaphragm cell is the least widely used cell, with the diaphragm process accounting or only 14% of total European chlorine production, which can be attributed to the huge environmental and health risks that the diaphragm cell poses.

In the diaphragm cell process the anode compartment is separated from the cathode area by a permeable asbestos diaphragm. The asbestos fibers produced from the diaphragm process can cause cancer. The only advantage of the diaphragm process is that it has low electrical energy consumption but not as low as the membrane cell. The chloral’s industry is clearly extremely important and has many benefits to human life. It would be unfeasible to discontinue such a large industry. However, there are big environmental problems associated with the mercury and diaphragm cells.

In order to make the industry more environmentally friendly the membrane cell should be universally used because of its low energy consumption and small environmental affects. Therefore the chloral’s industry is essential to human life and has to be continued. There are environmental impacts associated with the mercury and diaphragm processes but these could be overcome by using the membrane cell. Therefore the advantages of the chloral’s industry far outweigh the active impacts associated with the production processes.