{
  "url": "https://openlegislation.uk/eu-regulation-2004-648/annex-VIII/division-4/division-4.4/division-4.4.4",
  "json_url": "https://openlegislation.uk/eu-regulation-2004-648/annex-VIII/division-4/division-4.4/division-4.4.4.json",
  "legislation": "eur/2004/648",
  "legislation_title": "Regulation (EC) No 648/2004 of the European Parliament and of the Council of 31 March 2004 on detergents (Text with EEA relevance)",
  "legislation_url": "https://openlegislation.uk/eu-regulation-2004-648",
  "path": "annex/VIII/division/4/division/4.4/division/4.4.4",
  "kind": "division",
  "number": "4.4.4",
  "heading": null,
  "text": "Connect the exchange columns so that the cation-exchange column is placed on top of the anion-exchange column.\nHeat the exchange columns to 50 ° C using thermostatic control.\nHeat 5 000 ml of the solution obtained in item 4.4.2 to 60 ° C and pass the solution through the exchanger combination at a rate of 20 ml/min. Wash the columns with 1 000 ml hot isopropanol/water mixture (4.3.3).\nTo obtain the anionic surface active agents (MBAS), disconnect the KAT column. Using 5 000 ml ethanol/CO2 solution at 50 ° C (4.3.4), elute the soap fatty acids out of the KAT column. Reject the eluate.\nThen elute the MBAS out of the AAT column with 5 000 ml ammonium bicarbonate solution (4.3.5). Evaporate the eluate to dryness using a steam bath or in a rotary evaporator.\nThe residue contains the MBAS (as ammonium salt) and possible non-surfactant anionics that have no detrimental effect on the biodegradation test. Add deionised water to the residue until a definite volume is obtained and determine the MBAS content in an aliquot. The solution is used as a standard solution of the anionic synthetic detergents for the biodegradation test. The solution should be kept at a temperature below 5 ° C.\nRegeneration of ion exchange resins",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eur/2004/648/annex/VIII/division/4/division/4.4/division/4.4.4",
    "retrieved_at": "2026-11-01T14:55:38.850310+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}