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Reagents in EN 14719 (Pulp, paper andboard-Determinationof the DIPN content by solventextraction)

Posted Date:2025/12/30

3 Reagents

3.1 General

All reagents shall be of recognised analytical quality unless otherwise stated.

3.2 Standards

3.2.1 Diisopropyinaphthalene  (DIPN) (technical mixture of isomers)

The purity shall be given by the supplier or 2,6-Disopropylnaphthalene

3.2.2 Diethylnaphthalene (DEN), with a purity of 97 % or more

3.3 Chemicals, Acetone

3.4 Calibration stock solutions

3.4.1 Stock solution of diisopropylnaphthalene (DIPN) in acetone with an accurately known concentration of approximately 1 200 mg/l

Weigh accurately about 30 mg of disopropyinaphthalene (DIPN) (3.2.1) into a 25 ml volumetic flask. Fill the volumetric flask to approximately half the volume with acetone (3.3), shake to dissolve and dilute to the mark with acetone.

Calculate the concentration of diisopropyinaphthalene (DIPN) in mg/l, by using the exact mass taken and the purity.

3.4.2 Standard stock solution (A) with an accurately known concentration of approximately 12 mg/l

Transfer 1 ml of the 1 200 mg/l stock solution (3.4.1) into a 100 ml volumetric flask and dilute to the mark with acetone.

3.4.3 Standard stock solution (B) with an accurately known concentration of approximately 120 mg/l

Transfer 10 ml of the 1 200 mg/l stock solution (3.4.1) into a 100 ml volumetric flask and dilute to the mark with acetone.

3.5 Internal standard stock solution

Stock solution of diethylnaphthalene (DEN) (3.2.2) in acetone with a concentration of approximately 1 000 mg/l.

Weigh accurately approximately 50 mg of diethylnaphthalene (DEN) (3.2.2) into a 50 ml volumetric flask and dilute to the mark with acetone.