ASTM D2421-13

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D2421 −13
Standard Practice for
Interconversion of Analysis of C and Lighter Hydrocarbons
5
1
to Gas-Volume, Liquid-Volume, or Mass Basis
This standard is issued under the fixed designation D2421; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* For 1 mL gas at 15.6°C (60°F), 101.325 kPa (760 mm Hg),
1.1 This practice describes the procedure for the intercon-
version of the analysis of C and lighter hydrocarbon mixtures L 5 ~273.15/288.71! 3 ~M/22414! (1)
5
to gas-volume (mole), liquid-volume, or mass basis.
3 1/ relative density 3 0.999016
@ @ ~ ! ~ !##
1.2 The computation procedures described assume that
25
gas-volume percentages have already been corrected for non-
4.2252 310 3 M/relative density
~ !
idealityofthecomponentsasapartoftheanalyticalprocessby
5millilitres liquid at 15.6°C ~60°F!
which they have been obtained. These are numerically the
same as mole percentages.
where:
1.3 The procedure assumes the absence of nonadditivity
22414 = calculated from V=nRT/P,
corrections for mixtures of the pure liquid compounds. This is n = 1 g-mole,
approximately true only for mixtures of hydrocarbons of the R = 8314.472,
T = 273.15, and
same number of carbon atoms, and in the absence of diolefins
P = 101.325 kPa.
and acetylenic compounds.
2.3 Where ideal gas volumes have been measured at tem-
1.4 The values stated in SI units are to be regarded as the
peratures and pressures different from 15.6°C (60°F) at
standard. The values given in parentheses are for information
101.325 kPa (760 mm Hg), they shall be corrected to these
only.
conditions.
1.5 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
3. Significance and Use
responsibility of the user of this standard to establish appro-
3.1 For custody transfer and other purposes, it is frequently
priate safety and health practices and determine the applica-
necessary to convert a component analysis of light hydrocar-
bility of regulatory limitations prior to use.
bon mixture from one basis (either gas volume, liquid volume,
2. Source of Data
or mass) to another.
2.1 The basic values for the relative density 15.6/15.6°C
3.2 The component distribution data of light hydrocarbon
(60/60°F) of the pure compounds have been obtained from
mixtures can be used to calculate physical properties such as
TRC (formerly the Thermodynamics Research Center, and
relative density, vapor-pressure, and calorific value. Consistent
now part of NIST), except where otherwise noted. The values
and accurate conversion data are extremely important when
for methane, ethylene, and acetylene are not those of pure
calculating vapor, liquid, or mass equivalence.
materials but are assumed to apply as a component of a liquid
4. Procedure
mixture.
4.1 To convert from the original to the desired basis,
2.2 The conversion factors for 1 mL of ideal gas at 15.6°C
multiplyordividethepercentofeachcompoundintheoriginal
(60°F) and 101.325 kPa (760 mm Hg) to millilitres of liquid at
basis according to the schedule shown in Table 1. Perform the
15.6°C (60°F) have been calculated as follows:
calculation, using the corresponding factor indicated in Table
2. Carry at least one more significant figure in all of the
1
calculations than the number of significant figures in the
This practice is under the jurisdiction of ASTM Committee D02 on Petroleum
Products and Lubricants and is the direct responsibility of Subcommittee D02.H0
original analysis.
on Liquefied Petroleum Gas.
4.1.1 The factors or percentages may be multiplied by any
Current edition approved June 15, 2013. Published August 2013. Originally
constant number for convenience (such as moving the decimal)
approved in 1965. Last previous edition approved in 2002 as D2421 – 02 (2007).
DOI: 10.1520/D2421-13. without changing the end result.
*A Summary of Changes section appears at the end of this standard
Copyright ©ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA19428-2959. United States
1

---------------------- Page: 1 ----------------------
D2421−13
TABLE 1 Conversion Factors Scheduled
Factor Column in
Original Basis Desired Basis Operation
Table 2
Gas volume mass multiply by 1
Gas volume liquid volume multiply by 2
Mass gas volume divide by 1
Mass liquid volume divide by 3
Liquid volume gas volume divide by 2
Liquid volume mass multiply by 3
A
TABLE 2 Mass-Volume Data for Liquefied Petroleum Gases and Low Boiling Hydrocarbons
Column 1 Column 2 Column 3
Liquid Volume in mL of
1 mL of ideal gas at Relative Density 15.6/15.6°C
Compound Molecular M
...