Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
D2973-23 – Standard Test Method Technical Guide
ASTM D2973-23 outlines a chemical test method for determining the total nitrogen content in peat materials. The method involves converting nitrogen into ammonium salts via destructive digestion with a hot, catalyzed mixture of concentrated sulfuric acid and potassium sulfate. These salts are decomposed in alkaline solution, and ammonia is recovered by distillation and determined by acidimetric titration. The standard specifies the use of SI units and requires conformance to the significant digits guidelines in Practice D6026.
📐 Specimen Preparation and Types
The test requires a representative specimen from a representative sample, which is air dried following Method B of ASTM D2974. This preparation ensures consistent moisture levels for accurate nitrogen analysis. The specimen must be handled according to the guidelines to maintain representativeness.
| 🟦 Referenced Standard | 📏 Description |
|---|---|
| D653 | Terminology Relating to Soil, Rock, and Contained Fluids |
| D1193 | Specification for Reagent Water |
| D2974 | Test Methods for Determining Water (Moisture) Content, Ash Content, and Organic Material of Peat and Other Organic Soils |
| D3740 | Practice for Minimum Requirements for Agencies Engaged in Testing and/or Inspection of Soil and Rock as Used in Engineering Design and Construction |
| D4753 | Guide for Evaluating, Selecting, and Specifying Balances and Standard Masses for Use in Soil, Rock, and Construction Materials Testing |
| D6026 | Practice for Using Significant Digits and Data Records in Geotechnical Data |
These standards are integral for proper execution and reporting of the test method.
⚙️ Test Procedure and Summary
The test procedure involves destructive digestion of the specimen with a hot, catalyzed mixture of concentrated sulfuric acid and potassium sulfate to convert nitrogen into ammonium salts. These salts are subsequently decomposed in a hot alkaline solution, and the ammonia is recovered via distillation. The ammonia distillate is then determined by acidimetric titration to calculate the mass percent of nitrogen.
| 🎯 Step | ⚡ Details |
|---|---|
| Digestion | Specimen is digested with concentrated sulfuric acid and potassium sulfate catalyst at high temperature. |
| Alkaline Decomposition | Ammonium salts are decomposed in a hot alkaline solution. |
| Distillation | Ammonia is distilled from the mixture. |
| Titration | Ammonia is determined by acidimetric titration to quantify nitrogen content. |
⚠️ Mercury Warning: Mercury is a hazardous material. Handle mercury and mercury-containing products with caution. Consult the applicable Safety Data Sheet (SDS) for additional information. Be aware that selling mercury or mercury-containing products may be prohibited by law in your state or country.
📊 Key Measured Properties and Data Reporting
The key property measured is the mass percent of total nitrogen in the peat material. All observed and calculated values must conform to the guidelines for significant digits and rounding established in Practice D6026. The procedures specified in this standard are considered industry standard for data collection and calculation. Users should consider material variation and purpose when determining significant digits for reported data.
💡 Tip: Always refer to Practice D6026 for guidance on significant digits to ensure compliance with industry standards and to maintain consistency in data reporting.
❓ Frequently Asked Questions
🔍 What is the scope of ASTM D2973-23?
The standard covers a chemical test method for the determination of the mass percent of total nitrogen in peat materials.
💡 What units are used in the standard?
SI units are to be regarded as standard. No other units of measurement are included in this standard.
⚡ What safety concerns are addressed?
The standard includes a warning about mercury, which is hazardous to health and corrosive to materials. Users should follow safety practices and consult the SDS.
📌 How should the specimen be prepared?
A representative specimen is obtained from a representative sample and air dried following Method B of ASTM D2974.