Sodium hypochlorite, oxidising agent

Precipitate formation can occur upon contact of iajection water ions and counterions ia formation fluids. Soflds initially preseat ia the iajectioa fluid, bacterial corrosioa products, and corrosion products from metal surfaces ia the iajectioa system can all reduce near-weUbore permeability. Injectivity may also be reduced by bacterial slime that can grow on polymer deposits left ia the wellbore and adjacent rock. Strong oxidising agents such as hydrogen peroxide, sodium perborate, and occasionally sodium hypochlorite can be used to remove these bacterial deposits (16—18). 

This is a special chemical effectively used for column bioreactors. It is a volatile compound and strong oxidising agent. It boils at ambient temperature, therefore the solution of ethylene oxide (liquid phase) must be stored in a refrigerator (4 °C). An excellent oxidising agent such as a 3% sodium hypochlorite is used for chemical sterilisation of equipment. 

Several oxidising agents can be used (lead tetraacetate, N-bromosuccinimide, chlorine, etc). A mechanism is illustrated below for alkaline sodium hypochlorite. 

Sometimes bromides or related compounds are added to the hypochlorite liquor to accelerate the bleaching action. It is likely that sodium hypobromite is formed which is a stronger oxidising agent than hypochlorite. 

Sulphenamides can be prepared using a wide variety of oxidising agents. However, commercially, sodium hypochlorite or chlorine are most often used. With the increasing environmental pressure on chlorine oxidants, the industry is looking for alternative clean oxidants. 

Oxidation with relatively mild oxidising agents. Hydrogen peroxide and sodium hypochlorite are often cited, but a low hazard system worthy of testing out is ammonium persulphate,... 

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