In ecological chemistry, chemical oxygen need COD checks the dimension of oxygen that is eaten during the examination by specific natural compound. To put it simply the COD examination is used to determine the amount organic matter present in the specific natural compound. Its application is commonly in the dimension of natural contaminants existing in the surface water or river water and also to clean up the water. A typical approach for chemical oxygen need analysis is to respond the strong oxidizing chemical such as potassium dichromate or dichromate ion with the organic matter. Potassium dichromate oxidizes the whole organic matter to co2, ammonia and also water under acidic problem.
Chemical oxygen demand is a crucial criterion for the quality check of the water as it helps to know the result that will certainly released wastewater result will certainly carry the atmosphere. High chemical oxygen need level implies the greater amount of oxidixable raw material which in outcome less quantity of dissolved oxygen in the water. COD is one of the most beneficial test to know the level of pollution, water contains. As it takes long time to oxidizing chemical to oxidize the organic substance we can also utilize UV-VIS modern technology. By using this innovation, we can understand the COD in actual time. This system works with the assistance of UV lights. At specific wavelength the natural substance existing in the water, such as tannin, lignin and also other aromatic substances soaks up the UV rays. By determining wavelengths and making specific calibration we can acquire COD data.
COD WITH POTASSIUM DICHROMATE: mostly every type of natural compounds is oxidizied by means of boiling blend including natural compound with chromic and sulphuric acid. The sample of organic matter is refluxed with potassium dichromate in strong acidic remedy. The unused potassium dichromate used in the process is being titrated with the ferrous ammonium sulphate to know the specific amount of potassium dichromate which had actually been taken in and thus oxidizable issue is computed in terms of the potassium dichromate terms. Some examples with extremely low chemical oxygen demand require to be examined in reproduce to get the exact results.
CONSTRAINTS: it is mostly observed that the oxidation of the offered sample natural substance is about 90% to 95% that of academic worth. Organic compounds such as pyridine and related substance stand up to the oxidation. Volatile organic compounds additionally react symmetrical to which they touch with the oxidant. Straight chain aliphatic organic substance 857730-21-3 can easily be oxidized in the visibility of silver sulphate stimulant. Chloride ions or other halogen ions of bromide, iodide conveniently reacts with silver ion to create the precipitate of silver chloride. This sort of interference is adverse, which have a tendency to restrict the oxidizing activity of potassium dichromate. This leads to an error on the high side.