Overview
EN 14719:2005 - published by CEN - specifies a laboratory method for the determination of Diisopropylnaphthalene (DIPN) in pulp, paper and board by solvent extraction followed by gas chromatography–mass spectrometry (GC‑MS). Results are reported as mg of total DIPN isomers per kilogram of sample. The method is designed for quantitative determination with a limit of determination of about 0.6 mg/kg and is intended to detect DIPN as an adsorbed or encapsulated contaminant (often occurring in recovered fibres).
Key Topics and Requirements
- Scope & reporting: DIPN content expressed as mg DIPN isomers/kg paper, board or pulp; applicable to adsorbed and encapsulated forms.
- Principle: Solvent extraction (acetone) of test pieces, addition of an internal standard, and analysis by GC‑MS using peak area ratios.
- Reagents & standards:
- Diisopropylnaphthalene (technical mixture) as analyte standard.
- Diethylnaphthalene (DEN) (≥97 % purity) as internal standard.
- Acetone as extraction solvent.
- Sample preparation:
- Test pieces (approx. 2.00 g) extracted in 25 ml acetone with internal standard, ~16 h soak plus ultrasonic bath.
- Duplicate determinations recommended; include blank and control standard.
- Calibration & quantification:
- Two calibration ranges recommended (0.05–1.0 mg/l and 1–10 mg/l equivalents).
- Construct calibration by plotting DIPN/DEN peak area ratio vs mass of DIPN; correlation coefficient ≥ 0.996.
- Example GC‑MS operating conditions and diagnostic ions provided (DIPN ions m/z 155, 197, 212; DEN m/z 169).
- Apparatus: GC‑MS with capillary column (example: 5% phenylmethyl siloxane, 30 m × 0.25 mm × 0.25 µm), ultrasonic bath, microsyringes, PTFE‑lined screw vials.
- Quality control: Blank checks for contamination, control standard recovery within ±8% of true value.
Applications and Users
- Quality control and contaminant monitoring in pulp and paper mills, especially those using recovered fibres.
- Analytical and contract laboratories performing regulatory or customer‑driven screening of paper, board and pulp for DIPN contamination.
- Environmental and safety assessments where DIPN presence needs quantification.
- Product compliance testing for recycled‑fiber products and packaging materials where contaminant transfer is a concern.
Related Standards (applicable)
- Other CEN/TC 172 standards for pulp, paper and board testing and European methods for solvent extraction and GC‑MS analysis. Laboratories should align EN 14719:2005 procedures with national implementations and relevant laboratory accreditation requirements.
Keywords: EN 14719:2005, DIPN, diisopropylnaphthalene, paper testing, pulp testing, solvent extraction, GC‑MS, diethylnaphthalene, CEN, limit of determination 0.6 mg/kg.