Model 926 Chloride Analyzer
Sherwood model 926 is used to determine chloride ions. The technique is based on ‘Argentimetry’, the traditional titrimetric method that uses silver nitrate as a reagent. Like this classical method, the principle of Model 926 is based on the chemical formation of the insoluble salt silver chloride.
The main problem with the classical method is that the silver nitrate reagent could change during storage by a photometric reaction and that the end point of the titration is visually weak.
The method used in Model 926 is based on an absolute coulometric titration. The silver ions of the reagent are generated precisely and quantitatively at the time of the analysis by a constant current between the donor electrodes. The tipping point is detected by measuring electrodes that measure the change in conductivity when silver ions are present in excess in the solution.
Food and dairy industry
The measurement of the salt concentration (sodium chloride) in this industry is common practice. The ability to directly display the salt concentration makes this instrument a worldwide favourite with lab technicians.
Salt causes serious pollution in industrial processes. The sensitivity of the coulometric method makes it possible to measure in the ppm range of boiler feed water, polymer scrubbing, borehole slurries, as well as soil analysis et cetera. The 926 has proven to be a popular method for many studies on desalination and quality control in general.
The measurement of the chloride ion plays an essential role in monitoring the electrolyte balance of patients. In combination with sodium and potassium, this ion plays an important role in maintaining the balance between cells, plasma and interstitial fluid. Model 926s is also widely used in the diagnosis of Cystic Fibrosis. Model 926s measures samples with a volume of 20µL.
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