Study on formic functional group content determination.

In order to control potassium formic quality, detecting method of formic functional content was studied to optimize the ratio of sodium formate to potassium formate, and to make formate drilling fluid exhibits its characteristic fully. Formic functional group content in solid formate and in the filtrate of drilling fluid was introduced respectively, and influences of KMnO 4 concentration and addition on the determination were studied. In addition, formic functional group content of lab fluid and field fluid filtrates were determined. At the same time, effect of drilling fluid additives on the results was also analyzed. Lab data showed that this method is suitble for determining formic group content of formate additives and formate drilling fluid with the result is liable in high accuracy. Finally, the technical index of potassium formate was determined, that is: w(H 2O)≥8.0%, w(KCOOH)(purity)90%, w(K +)≥40.0%, density of saturated salt solution≥1.55 g/cm 3.