Overview
ISO 2096:1972 - "Glycerols for industrial use - Methods of sampling" sets out standardized procedures to obtain representative samples of crude or refined glycerol (glycerine) during filling or from drums and fixed/transportable tanks. The standard emphasizes sampling during filling where possible, describes special precautions for glycerol’s very hygroscopic nature, and defines the sampling principle: take equal aliquots at regular intervals during filling, mix/homogenize the successive grabs, then prepare laboratory samples.
Key topics and technical requirements
- Sampling principle: successive, equal-quantity grabs distributed uniformly during filling; combine and homogenize these grabs to form the global sample, then take laboratory sub-samples.
- Preferred timing: sample during filling whenever feasible to minimize heterogeneity caused by settling or stratification.
- Hygroscopic precautions: protect all samples and equipment from moisture and humid air; use hermetically closable containers and keep them closed between operations.
- Sample containers and sealing:
- Laboratory bottles: chemically resistant glass with ground-glass stoppers; where appropriate, screw caps lined with polyethylene or aluminium are allowed. Lab bottles should be sealed by the sampler (e.g., sealing wax).
- For lots with suspended solids, fill bottles to two-thirds to aid homogenization; otherwise fill completely.
- Apparatus examples:
- Discontinuous “ladle” (300–500 ml), brass for crude glycerol or stainless steel for refined grades.
- Tubular probe / sampling device for continuous sampling through the filling line; collector vessels (glass or stainless steel) with vents to avoid moisture ingress.
- Weighted bottle, probe with opening/closing mechanisms, and bung wipers for drum/tank sampling.
- Sample sizing:
- Global sample recommendations: ≈1 kg of global sample per tonne of glycerol, with a maximum around 50 kg.
- Laboratory sub-samples: typically about 500 g each.
- Handling of deposits: when solid deposits are present, sample the liquid phase and the deposit separately; re-suspend deposits by warming/rotation where possible, and record deposit mass and nature in the sampling report.
Applications and users
- Quality control laboratories and testing laboratories verifying glycerol quality.
- Producers and refiners documenting product lots during filling and dispatch.
- Buyers, inspectors and transport operators performing acceptance sampling on delivered drums or tank shipments.
- Arbitration and dispute resolution where sealed buyer/seller/arbiter samples are required.
Related standards
- ISO 2096 complements other ISO guidance and national standards on sampling liquids and chemical products. Users should consult relevant ISO and industry standards for complementary testing methods and safety handling.
Keywords: ISO 2096, glycerol sampling, glycerine sampling, industrial glycerol, hygroscopic handling, tank sampling, drum sampling, laboratory samples, homogenization.