Hydrocarbons, C18-C24, iso-alkanes <2% aromatics

Melting point / freezing point

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

melting point/freezing point

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

1. Hypothesis for the analogue approach:
The hypothesis for the analogue approach is that the test substance GTL Gasoil is the starting material from which the registration substance, Hydrocarbons, C18-C24, iso-alkanes, <2% aromatics (GS310), is produced by fractional distillation. The source substance contains constituents of the target substance, Hydrocarbons, C18-C24, iso-alkanes, <2% aromatics, although it covers a wider carbon number distribution. The substances therefore have qualitatively similar properties (RAAF Scenario 2 applies).
2. Source and target chemical(s)
The source substance GTL Gasoil (C8-C26) (C8-C26 branched and linear hydrocarbons – Distillates) is the substance from which the registration substance is produced. GTL Gasoil is composed of linear, branched and cyclic hydrocarbons of chain length C8-C26.
The target substance, Hydrocarbons, C18-C24, iso-alkanes, <2% aromatics, is composed linear, branched and cyclic hydrocarbons of chain length C18-24
3. Analogue approach justification
The constituents of the source and target substances are all hydrocarbons. Identical constituents have identical physicochemical properties.

Reason / purpose for cross-reference:

read-across source

Melting / freezing pt.:

< 253 K

Atm. press.:

1 013 hPa

Reference 2

Endpoint:

melting point/freezing point

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

March 2005

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study conducted to GLP and in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not effect the quality of the relevant results. Read-across is considered to be reliability 2.

Justification for type of information:

See Melting point / freezing point Target record

Reason / purpose for cross-reference:

other: Target record

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

method to determine freezing temperature

Remarks:

Crystallisation point measure

Melting / freezing pt.:

< -20 °C

Atm. press.:

1 013 hPa

Determination 1

Time (s)	Temperature (K)	Time (s)	Temperature (K)
0	294	1260	267
30	293	1290	266
60	292	1320	266
90	291	1350	266
120	290	1380	265
150	289	1410	265
180	287	1440	265
210	287	1470	265
240	286	1500	265
270	284	1530	264
300	283	1560	264
330	282	1590	264
360	282	1620	264
390	281	1650	263
420	280	1680	263
450	279	1710	263
480	279	1740	263
510	278	1770	262
540	277	1800	262
570	276	1830	262
600	276	1860	262
630	275	1890	262
660	275	1920	261
690	274	1950	261
720	274	1980	261
750	274	2010	261
780	273	2040	260
810	273	2070	260
840	272	2100	260
870	272	2130	260
900	271	2160	259
930	271	2190	259
960	270	2220	259
990	270	2250	259
1020	270	2280	258
1050	269	2310	258
1080	269	2340	258
1110	269	2370	257
1140	268	2400	257
1170	268	2430	257
1200	267	2460	257
1230	267	2490	257
2520	257	2880	254
2550	256	2910	254
2580	256	2940	254
2610	256	2970	254
2640	256	3000	254
2670	255	3030	253
2700	255	3060	253
2730	255	3090	253
2760	255	3120	253
2790	255	3150	253
2820	255	3180	253
2850	254	3210	252

Determination 2

Time (s)	Temperature (K)	Time (s)	Temperature (K)
0	294	1080	262
30	292	1110	262
60	290	1140	262
90	288	1170	261
120	286	1200	261
150	284	1230	261
180	283	1260	260
210	281	1290	260
240	280	1320	259
270	279	1350	259
300	277	1380	258
330	276	1410	258
360	275	1440	258
390	275	1470	257
420	274	1500	257
450	274	1530	257
480	273	1560	257
510	272	1590	256
540	272	1620	256
570	271	1650	256
600	270	1680	256
630	270	1710	256
660	269	1740	255
690	268	1770	255
720	268	1800	255
750	267	1830	255
780	267	1860	254
810	266	1890	254
840	266	1920	254
870	265	1950	254
900	265	1980	253
930	264	2010	253
960	264	2040	253
990	263	2070	253
1020	263	2100	253
1050	263	2130	252

Calculation

Measured temperatures were converted from °C to K using the following equation:

T = t + 273.15

where:

T = temperature (K)

t = temperature (°C)

Observations

The test material became increasingly opaque and viscous from approximately 275 K, resulting in a white, opaque, viscous ‘slush-like’ state on completion of the test.

Conclusions:

The true freezing temperature of the test material, that at which it completely solidifies, has been determined to be less than 253 ± 0.5 K. However on cooling, the test material became increasingly opaque and viscous from approximately 275 K, resulting in a white, opaque, „slush-like“ state on
completion of each test.

Executive summary:

The freezing temperature of the test material was determined using EU Method A.1, whereby the following method was used: Crystallisation point measure.

The true freezing temperature, that at which it completely solidifies, has been determined to be less than 253 ± 0.5 K (arithmetic mean of two determinations). However on cooling, the test material became increasingly opaque and viscous from approximately 275 K, resulting in a white, opaque, „slush-like“ state on completion of each test.

Description of key information

pour point of the test material: <253 ± 0.5 K.

Additional information

The pour point of the read-across substance (Distillates (Fischer-Tropsch), C8-26, branched and linear) was determined using Method A1 of Commission Directive 92/69/EEC, and was determined to be<253 ± 0.5 K.