Isooctane , Spectrum , 540-84-1
Synonym(s):
2,2,4-Trimethylpentane;2,2,4-Trimethylpentane, Isobutyltrimethylmethane, iso-Octane;Isooctane;TMP
CAS NO.：540-84-1
Empirical Formula: C8H18
Molecular Weight: 114.23
MDL number: MFCD00008943
EINECS: 208-759-1
PRODUCT Properties
| Melting point: | -107 °C |
| Boiling point: | 98-99 °C(lit.) |
| Density | 0.692 g/mL at 25 °C(lit.) |
| vapor density | 3.9 (vs air) |
| vapor pressure | 41 mm Hg ( 21 °C) |
| refractive index | n |
| Flash point: | 18 °F |
| storage temp. | Store at +5°C to +30°C. |
| solubility | water: insoluble |
| form | Liquid |
| pka | >14 (Schwarzenbach et al., 1993) |
| Specific Gravity | 0.692 (20/4℃) |
| color | APHA: ≤10 |
| Relative polarity | -0.4 |
| explosive limit | 1%(V) |
| Odor Threshold | 0.11ppm |
| Water Solubility | INSOLUBLE |
| FreezingPoint | -107.52℃ |
| λmax | λ: 205 nm Amax: 1.00 λ: 225 nm Amax: 0.10 λ: 254 nm Amax: 0.01 |
| Merck | 14,5193 |
| BRN | 1696876 |
| Henry's Law Constant | 3.23 at 25 °C (Mackay and Shiu, 1981) |
| Exposure limits | ACGIH TLV: TWA for all isomers 300 ppm (adopted). |
| Dielectric constant | 2.1（Ambient） |
| Stability: | Stable. Highly flammable. Incompatible with oxidizing agents, reducing agents. |
| LogP | 4.373 (est) |
Description and Uses
Isooctane is a flammable liquid isomer of octane. It is best known for defining the octane
number to rate the antiknock quality of gasoline, which is related to engine performance.
Since 1930, many chemical processes, such as alkylation
and polymerization, have been developed to increase the production of branched compounds
in refi nery operations. High octane numbers in gasoline are those associated with the alkenes
(olefins) and aromatics, especially akyl benzene compounds. For example, 2-pentene has a
RON of 154. Benzene itself has a RON of 98, but 1,3,5-trimethylbenzene has a RON of 170.
The highest octane numbers in gasoline are associated with cyclic alkenes, but these account
for only a minute fraction of gasoline.
In determining octane numbers of fuels; in spectrophotometric analysis; as solvent and thinner.
Safety
| Symbol(GHS) |     GHS02,GHS07,GHS08,GHS09 |
| Signal word | Danger |
| Hazard statements | H225-H304-H315-H336-H410 |
| Precautionary statements | P210-P273-P301+P310+P331-P302+P352 |
| Hazard Codes | F,Xn,N |
| Risk Statements | 11-38-50/53-65-67 |
| Safety Statements | 9-16-29-33-60-61-62 |
| RIDADR | UN 1262 3/PG 2 |
| WGK Germany | 1 |
| RTECS | SA3320000 |
| Autoignition Temperature | 745 °F |
| TSCA | Yes |
| HS Code | 2901 10 00 |
| HazardClass | 3 |
| PackingGroup | II |
| Toxicity | LD50 orally in Rabbit: > 2500 mg/kg |
