Active Standard ASTM D7423 | Developed by Subcommittee: D02.D0.04
Book of Standards Volume: 05.04
Significance and Use
The determination of oxygenates is important in the manufacture of ethene, propene, 1-3 butadiene, C4 hydrocarbons, and C5 hydrocarbons. Alcohols, ethers, aldehydes, and ketones are trace impurities in these hydrocarbons. Oxygenates decrease catalyst activity in downstream polymerization processes.
1.1 This test method covers the gas chromatographic procedure for the quantitative determination of organic oxygenates in C2, C3, C4, and C5 matrices by multidimensional gas chromatography and flame ionization detection. This test method is applicable when the hydrocarbon matrices have a final boiling point not greater than 200°C. Oxygenate compounds include, but are not limited to, those listed in Table 1. The linear working range for oxygenates is 0.50 mg/kg to 100 mg/kg.
1.2 This test method is intended to determine the mass concentration of each oxygenate in the hydrocarbon matrix. Oxygenate compound identification is determined by reference standards and column elution retention order.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
TABLE 1 Oxygenates and Typical Retention Times
|Components||Retention Time (min)|
|Ethyl tert-butyl ether||10.66|
|Methyl tert-butyl ether (MTBE)||10.92|
|Tertiary amyl methyl ether (TAME)||13.19|
|N-propyl alcohol and isopropanol||19.20 (co-elution)|
|Isobutanol, Tert-butyl alcohol, Sec-Butanol||20.24 (co-elution)|
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D1265 Practice for Sampling Liquefied Petroleum (LP) Gases, Manual Method
D1835 Specification for Liquefied Petroleum (LP) Gases
D4175 Terminology Relating to Petroleum, Petroleum Products, and Lubricants
D6299 Practice for Applying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measurement System Performance
D6849 Practice for Storage and Use of Liquefied Petroleum Gases (LPG) in Sample Cylinders for LPG Test Methods
E355 Practice for Gas Chromatography Terms and Relationships
ICS Number Code 71.080.01 (Organic chemicals in general)