IP 501 for Determination of Elements in residual Fuel Oil
IP 501 Determination of Aluminium, Silicon, Vanadium, Nickel, Iron, Sodium, Calcium, Zinc and Phosphorus in Residual Fuel Oil by Ashing, Fusion and Inductively Coupled Plasma Emission Spectrometry
4 Reagents and materials
4.1 General
All reagents shall be of analytical reagent grade or of higher purity and water shall be of at least grade 3 purity as specified in ISO 3696.

4.2 Potassium hydrogensulfate (KHSO4)
Fused solid.

4.3 Ashing agent
Sulfur, 99,9 % (m/m) minimum purity.

4.4 Propan-2-ol

4.5 Toluene

4.6 Toluene/propan-2-ol mixture (1 + 1)
Mix equal volumes of toluene and propan-2-ol.

4.7 Hydrochloric acid
Concentrated, 36 % (m/m) HCl.
4.7.1 Hydrochloric acid solution (1 + 1). Mix equal volumes of hydrochloric acid (4.7) and water.

4.7.2 Hydrochloric acid solution (1 + 2). Mix one volume of hydrochloric acid (4.7) with two volumes of water.

4.8 Flux
Mixture of 90 % (m/m) dilithium tetraborate (Li2B4O7) and 10 % (m/m) lithium fluoride (LiF).

4.9 Tartaric acid
4.9.1 Tartaric acid/hydrochloric acid solution. Dissolve 5 g of tartaric acid in approximately 500 ml of water acidified with 40 ml of hydrochloric acid (4.7) and dilute to 1 000 ml with water.

4.10 Nitric acid
Concentrated, 70 % (m/m) HNO3.
4.10.1 Nitric acid solution (1 + 1). Mix equal volumes of nitric acid (4.10) and water.

4.11 Standard solutions
4.11.1 Aluminium standard solution. Use either a commercially available aluminium standard solution of 1 000 mg/l aluminium content, or prepare in the manner described in 4.11.1.1.
4.11.1.1 Dissolve 1,000 g of aluminium metal wire, of minimum purity 99,9 % Al, in 50 ml hydrochloric acid (4.7) with gentle heating in a 400 ml beaker (5.13). Cool, transfer to a 1 000 ml volumetric flask (5.9), and dilute to the mark with water.

4.11.2 Silicon standard solution. Use either a commercially available silicon standard solution of 1 000 mg/l silicon content, or prepare in the manner described in 4.11.2.1.
4.11.2.1 Fuse 2,140 g of silicon dioxide, of minimum purity 99,99 % SiO2, with 8 g of sodium hydroxide in a zirconium crucible fitted with a close-fitting lid (5.4) at dull re heat until a clear melt is obtained. Cool and dissolve the solidified melt in 100 ml of hydrochloric acid solution (4.7.2) in a 400 ml beaker (5.13). Cool, transfer to a 1 000 ml volumetric flask (5.9), make up to the mark with water, followed by immediate transfer to a plastic bottle (5.15) for longer-term storage.

4.11.3 Vanadium standard solution. Use either a commercially available vanadium standard solution of 1 000 mg/l vanadium content, or prepare in the manner described in 4.11.3.1.
4.11.3.1 Dissolve 1,000 g of vanadium metal, of minimum purity 99,9 % V, in 40 ml of nitric acid (4.10) with gentle heating in a 400 ml beaker (5.13). Cool, transfer to a 1 000 ml volumetric flask (5.9) and make up to the mark with water.

4.11.4 Nickel standard solution. Use either a commercially available nickel standard solution of 1 000 mg/l nickel content, or prepare in the manner described in 4.11.4.1.
4.11.4.1 Dissolve 1,000 g of nickel metal of minimum purity 99,9 % Ni, in 40 ml of nitric acid solution (4.10.1) with gentle heating in a 400 ml beaker (5.13). Cool, transfer to a 1 000 ml volumetric flask (5.9) and make up to the mark with water.

4.11.5 Iron standard solution. Use either a commercially available iron standard solution of 1 000 mg/l iron content, or prepare in the manner described in 4.11.5.1.
4.11.5.1 Dissolve 1,000 g of iron metal of minimum purity 99,9 % Fe, in 40 ml of hydrochloric acid solution (4.7.1) with gentle warming in a 400 ml beaker (5.13). Cool, transfer to a 1 000 ml volumetric flask (5.9) and make up to the mark with water.

4.11.6 Sodium standard solution. Use either a commercially available sodium standard solution of 1 000 mg/l sodium content, or prepare in the manner described in 4.11.6.1.
4.11.6.1 Dissolve 2,542 g±0,001 g of sodium chloride (NaCl) in water in a 400 ml beaker (5.13). Transfer to a 1 000 ml volumetric flask (5.9), make up to the mark with water, and mix.

4.11.7 Calcium standard solution. Use either a commercially available calcium standard solution of 1 000 mg/l calcium content, or prepare in the manner described in 4.11.7.1.
4.11.7.1 Dissolve 2,498 g±0,001 g of calcium carbonate(CaCO3) in water in a 400 ml beaker (5.13) with 100 ml water and add dropwise 10 ml of hydrochloric acid solution (4.7.1). Transfer to a 1 000 ml volumetric flask (5.9), make up to the mark with water, and mix.

4.11.8 Zinc standard solution. Use either a commercially available zinc standard solution of 1 000 mg/l zinc content, or prepare in the manner described in 4.11.8.1.
4.11.8.1 Dissolve 1,000 g±0,001 g of zinc metal in minimum volume of hydrochloric acid solution (1 + 1)(4.7.1) in a 400 ml beaker (5.13). Transfer to a 1 000 ml volumetric flask (5.9), make up to the mark with water, and mix.

4.11.9 Phosphorus standard solution. Use either a commercially available phosphorus standard solution of 1 000 mg/l phosphorus content, or prepare in the manner described in 4.11.9.1.
4.11.9.1 Dissolve 4,264 g±0,001 g diammonium hydrogen phosphate (NH4)2HPO4 in water in a 400 ml beaker (5.13). Transfer to a 1 000 ml volumetric flask (5.9), make up to the mark with water, and mix.