This paper is based uPon the principles of volumetric method for determination of potassium with sodium tetraphenylboron and quaternary ammonium salt. A linear equation was found between volume (V) of quaternary ammonium salt and quantity (K) of potassium in sample. On the basis of this equation,the use of working curves has been suggested. The results of the experiments indicated that the linear relation between V and K is very good when the quantity of potassium in sample is more than 0.Smg. This method is also suitable for determination of potassium in various salt solution. With the increase of concentration of the salt solution, Which has the same amount of potassium, The volume of quaternary ammonium salt solution decreases regularly. The influence of co-existance and interference ions can be eliminated by using this working curve method.As compared with the original method,this method is not only accurate and precise but also rapid, simple and convenient. It has been tested by the determination of potassium in a sea water sample and the standard deviation is found to be≤±0.001mg/ml.
