ICP-AES Determination of Potassium in Oil Field Oil Sludge

ICP-AES was applied to the determination of potassium in oil field oil sludge. The water,oil and slag in the oil field oil sludge sample were separated with Soxhlet extraction (heating reflux time found was 1 h after clarification of the extract), and then the slag was digested with hydrochloric acid, nitric acid, hydrofluoric acid and perchloric acid. Linear relationship between values of emission intensity and mass concentration of potassium was obtained in the range of 1.0-80 mg·L^-1, with detection limit (3s) of 3.03 μg·L^-1. On the base of oil sludge samples from station of ZW and T83, test for recovery was made by standard addition method and values of recovery found were 98.4%, 102% respectively, with RSD's (n=5) of 0.69%, 0.63% respectively.