Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
D2359-24 – Standard Test Method Technical Guide
ASTM D2359-24 specifies the requirements for refined benzene-535, a high-purity aromatic hydrocarbon used as a precursor in numerous chemical syntheses. This standard provides a comprehensive framework for quality control, incorporating multiple test methods to ensure product consistency and purity. The standard is crucial for industries like pharmaceuticals, plastics, and rubber manufacturing.
📐 Specification Scope and Referenced Standards
The scope of D2359-24 defines benzene-535 as having a solidification point of 5.35°C. It requires adherence to SI units and mandates rounding of test values per Practice E29. The standard references over 20 ASTM methods for evaluating properties such as acid wash color, solidification point, chloride content, and trace impurities. Notable among these are D848 for acid wash color, D852 for solidification point, and D7504 for trace impurities by gas chromatography. These references ensure consistent testing protocols across the industry.
⚙️ Test Methods for Quality Assurance
A variety of test methods are prescribed to verify the quality of refined benzene-535. The table below outlines key methods and their purposes:
| 🟦 Standard | 📏 Property | 📐 Application |
|---|---|---|
| D848 | Acid Wash Color | Assesses color reaction to detect impurities |
| D852 | Solidification Point | Determines purity via freezing point measurement |
| D4735 | Thiophene Content | GC analysis for trace sulfur compounds |
| D5194 | Chloride Content | Trace chloride determination in liquids |
| D5386 | Color | Color measurement using tristimulus colorimetry |
| D7504 | Trace Impurities | GC detection of monocyclic aromatic impurities |
These methods collectively ensure that benzene-535 meets stringent industrial purity standards.
📊 Physical and Chemical Property Requirements
Refined benzene-535 must achieve a solidification point of at least 5.35°C per D852 or D6875. The standard imposes limits on thiophene, chloride, and color, as determined by respective test methods. All results must be rounded to the nearest unit in the last digit of the specification limit, following Practice E29. Safety compliance with OSHA and local regulations is mandatory.
⚠️ Warning: Benzene is a hazardous chemical. Always consult Safety Data Sheets and adhere to regulatory guidelines for safe handling.
💡 Tip: For accurate conformance testing, ensure all instruments are calibrated per the referenced ASTM methods and samples are handled as per Practice D3437.
❓ Frequently Asked Questions
🔍 What is the meaning of “refined benzene-535”?
The term “535” refers to the minimum solidification point of 5.35°C, which is a key specification for purity in this grade of benzene.
💡 How do I determine conformance with D2359-24?
Conformance is confirmed by testing using the specified ASTM methods and rounding the results to the nearest unit as per Practice E29 to compare with the specification limits.
⚡ What are the main safety concerns with benzene?
Benzene is known to be carcinogenic and highly flammable. Users must follow OSHA regulations, use personal protective equipment, and ensure proper ventilation.
📌 Which standard is used for testing chloride in refined benzene?
Several methods are available, including D5194 for trace chloride, D5808 for microcoulometry, D7359 for combustion ion chromatography, and D7536 for X-ray fluorescence.