SIST EN 15922:2011

Overview

SIST EN 15922:2011 is a European standard developed by CEN that specifies the procedure for the extraction of soluble phosphorus in fertilizers using Petermann’s method at ambient temperature. This extraction method focuses on phosphorus soluble in cold alkaline ammonium citrate and applies exclusively to disintegrated phosphate fertilizers. The standard ensures consistent and reliable determination of soluble phosphorus content, critical for fertilizer quality control and compliance with EU regulations.

Key Topics

• Scope and Applicability
  The procedure targets phosphorus extraction from disintegrated phosphate fertilizers using an alkaline ammonium citrate solution (Petermann’s solution) under ambient conditions (~20 °C).

• Petermann’s Solution Composition
  The extracting agent consists of:

  • Citric acid monohydrate (173 g/l)
  • Ammoniacal nitrogen (42 g/l) from ammonia
  • pH range of 9.4 to 9.7

• Sample Preparation
  Samples must be prepared according to EN 1482-2, recommending grinding to ensure homogeneity.

• Extraction Procedure

  • Weigh 2.5 g of the prepared sample precisely.
  • Add Petermann’s solution and shake vigorously to prevent lumps.
  • Make up to 250 ml in a graduated flask and close with a stopper.
  • Shake on a rotary shaker at 35–40 turns per minute for 2 hours.
  • Filter immediately using phosphate-free filters and discard the initial filtrate.
  • Collect filtrate for phosphorus analysis as per CEN/TS 15959.

• Reagent Preparation and Quality Control
  Instructions for preparing Petermann’s solution from diammonium citrate or citric acid and ammonia are detailed, including adjustment of ammoniacal nitrogen content verified by EN 15475 methods.

• Normative References
  Includes important related standards such as EN 1482 (sampling and sample preparation), EN 12944 (fertilizer vocabulary), and CEN/TS 15959 (phosphorus determination).

Applications

SIST EN 15922:2011 is essential for laboratories and manufacturers in the fertilizer industry who need to:

• Determine soluble phosphorus content for quality assurance and regulatory compliance.
• Ensure consistent phosphorus extraction under standardized ambient temperature conditions, facilitating product comparison and classification.
• Support regulatory frameworks for fertilizer labeling, composition, and environmental compliance within the European Union and member countries.
• Facilitate research and development of phosphate fertilizer formulations by providing a reliable method for phosphorus solubility assessment.

This standard is particularly valuable for manufacturers involved in phosphate fertilizer production and testing laboratories performing routine or certification analyses.

Related Standards

• EN 1482-2: Fertilizers and liming materials - Sampling and sample preparation - Part 2: Sample preparation
  Provides guidelines for preparing representative and homogenous samples prior to analysis.

• EN 12944-1 and EN 12944-2: Fertilizer Vocabulary
  Defines terms related to fertilizers and soil improvers, ensuring consistent communication in the industry.

• EN 15475: Fertilizers - Determination of ammoniacal nitrogen
  Specifies the method for ammoniacal nitrogen determination, critical to preparing Petermann’s solution correctly.

• CEN/TS 15959: Fertilizers - Determination of extracted phosphorus
  Details the quantitative determination of phosphorus content in extracts obtained from methods like EN 15922.

• Regulation (EC) No 2003/2003
  European Parliament regulation on fertilizers, referencing this and other analytical methods for compliance.

Keywords: SIST EN 15922:2011, Petermann extraction, soluble phosphorus, fertilizers, phosphate extraction, alkaline ammonium citrate, fertilizer testing, fertilizer quality, phosphorus determination, fertilizer standards, CEN fertilizer methods, EU fertilizer regulations.