Gasoline INDEX

Reforming technology Reformulated gasoline Refraction Refractive index Refractive indexes... 

It is not surprising that the data produced as total petroleum hydrocarbons (EPA 418.1) suffer from several shortcomings as an index of potential ground-water contamination or health risk. In fact, it does not actually measure the total petroleum hydrocarbons in the sample but rather, measures a specific range of hydrocarbon compounds. This is caused by limitations of the extraction process (solvents used and the concentration steps) and the reference standards used for instrumental analysis. The method specifically states that it does not accurately measure the lighter fractions of gasoline [benzene-toluene-ethylbenzene-xylenes fraction (BTEX)], which should include the benzene-toluene-ethylbenzene-xylenes fraction. Further, the method was originally a method for water samples that has been modified for solids, and it is subject to bias. 

Uses Determining refractive index of minerals paint diluent dyed hexane is used in thermometers instead of mercury polymerization reaction medium calibrations solvent for vegetable oils alcohol denaturant chief constituent of petroleum ether, rubber solvent, and gasoline in organic synthesis. 

Colorless liquid burns with orange flame with green margin refractive index 1.5198 density 1.653 g/mL at 20°C insoluble in water slightly soluble in ethanol soluble in benzene, toluene, gasoline, and petroleum ether. 

The reported octane number for a gasoline is actually a calculated average of the RON and MON. This value is called the Antiknock Index and is stated as follows ... 

Remarkable increases in the aromatics content of gasolines and the octane number were obtained with synthetic-aluminum-silicate-supported catalysts (43), as shown in Table XXI. The experiments were made at 250 atm. pressure with petroleum gas oil of 0.846 sp. gr. and a boiling range of 187° to 330°C. Temperatures around 400°C. were used and were adjusted to obtain approximately the same conversion for both catalysts. The silicate catalyst is less active. The high aromatics content obtained with the aluminum silicate catalyst is especially evident in the higher fractions. The amount of branched-chain paraffin hydrocarbons is not greatly different, as shown by the octane number of the aromatic free fractions, used as an index. 

Theoretically, the possible aromatics yidd is much higher if the feed contains a larger amount of direct precursors N + 2A normally varies from 30 to 80). With present-day catalysts, however, a high yield can be achieved, even for gasolines with a low V +14 index. The factor Kuqp fr related to N +14 by the following empirical equation ... 

Over all of the products, the production cost is 7.19/GJ. This produces ethane at 373/t. However, if the natural gasoline is sold according to the prevailing crude oil price (assumed to be 70/bbl) then this will generate by-product credit of 556 million this is based on valuing the gasoline as naphtha with oil at 70/barrel. The basis of this oil price as a reference (index) price is discussed in the Appendix. This approach reduces the production costs and hence the unit ethane and LPG costs. The ethane production cost is 341/t. 

Xylene is one of the organic compounds found in gasoline, and high concentrations have been measured at gasoline stations. If the yearly average concentration of. xylene at a neighborhood gas station is 220 pg/ni, wl it is the hazard index associated with long term exposure Likew ise, if the peak 1-hour concentration near the pumps is 1,000 (.lg/m wliat is tlie hazard index for short term exposure Note die clu-onic and acute response exposure levels for xylene are 300 ).ig/ni and 4,400 pg/m, respectively. 

In 1974, it was reported that "for meeting the challenge of unleaded gasoline, U. S. refiners have built up their octane making capability to the highest level in history, A rough index of this is the combined catalytic reforming and alkylation capacity as a percent of crude capacity. That number has risen from about 25% ten years ago to 30% in 1974". It is understood that... 

Four types of REY zeolite (Si/Al = 4.8) with different crystal sizes and acidic properties were used. The physical and chemical properties of the fresh zeolites are given in Table 6.4. Polyethylene plastics-derived heavy oil, shown in Table 6.2, was used as the feed oil. The cracking reaction was conducted in a tubular reactor filled with catalyst particles under the following conditions time factor W/F = 0.2-3.0 kg-catkg oil h and reaction temperature = 300-450°C. The lumping of reaction products were gas (carbon number 1-4), gasoline (5-11), heavy oil (above 12), and a carbonaceous residue referred to as coke. The index of the gasoline quality used was the research octane number (RON), which was calculated from Equation 6.1 [31]. 

The catalytic cracking of polypropylene waste in a flnidized-bed reactor was reported by Ji [12]. It gave a yield of liquid product of 50%, the research octane number of the gasoline prodnced from plastic waste was 86, and the cetane index of the diesel fuel produced from the plastic waste was 43. 

Besides feed properties and operational variables, the type of catalyst has a profound effect on hnal olehns level in the gasoline prodnct. Catalysis with better metal tolerance, especially to nickel and vanadium, are most suitable for olehn reduction. Catalyst capacity to saturate olehns and to form corresponding paraffins depend upon the hydrogen transfer index (HTI). 

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