Determination of Potassium, Sodium, and Total Alkalies in Portland Cement, Fly Ash, Admixtures, and Water of Concrete by a Simple Flow Injection Flame Photometric System

Table 1

Recoveries of sodium and potassium determined by FI-FES.

Sample	Na concentration found (mg L^−1)			K concentration found (mg L^−1)
	Original sample	With 5 mg L^−1 Na added	% Recovery	Original sample	With 5 mg L^−1 K added	% Recovery
Cement	9.76±0.04	14.35±0.01	91.8	12.37±0.25	16.66±0.09	85.8
Fly ash	4.32±0.05	8.80±0.02	89.6	4.98±0.07	9.31±0.17	86.6
Admixture 1	8.77±0.01	13.86±0.18	101.8	0.00±0.00	5.31±0.08	106.2
Admixture 2	6.19±0.11	10.65±0.05	89.2	1.87±0.18	6.59±0.15	94.4