Reformulated Gasoline. Reformulated gasoline (RFG) is gasoline blended to burn more cleanly than conventional gasoline and to reduce smog-forming and toxic pollutants in the air we breathe. The RFG program was mandated by Congress in the 1990 Clean Air Act amendments.
Reformulated Gasoline. Reformulated gasoline (RFG) is gasoline blended to burn more cleanly than conventional gasoline and to reduce smog-forming and toxic pollutants in the air we breathe.
In cities with high smog levels, providing a reformulated gasoline option is mandatory, while in other cities it is optional. Approximately 30 percent of the gasoline currently sold in the United States is reformulated.
Reformulated gasoline produces between 5 and 17 percent less pollution than conventional gasoline. Reformulated gasoline is created by using smaller amounts of benzene than in conventional gases. Safeopedia Explains Reformulated Gasoline A reformulated gasoline program was mandated by the US Congress in the 1990 Clean Air Act amendments.
Due to more stringent fuel specifications reformulated gasoline must maintain high octane rating with reduced benzene and aromatic content. The loss of octane rating, due to the reduction of aromatic content of reformate, can partially be compensated by enhanced isomerization activity of new type of multimetallic reforming catalysts. As far as Pt-Re/Аl2 О 3 catalyst is still the most widely used one in naphtha reforming [1], this work was aimed to reduce the yield of benzene and aromatics in the reforming of n-octane and a wide boiling range straight ran sulfur free naphtha over two commercial-bimetallic catalysts via modification with tin tetraethyl using CSR [2].
Oxygenated gasolines have lower heating values because the heating values of the oxygenate components are lower than those of the hydrocarbons they displace. The percent decrease in heating value is close to the mass percent oxygen in the gasoline. Federal reformulated gasoline and California Phase 2 reformulated gasoline must be oxygenated year round to average oxygen content of about 2% by mass. As a result, their heating values are about 2% lower than conventional gasoline. In addition, California Phase 2 reformulated gasoline sets some limits on distillation temperatures and aromatics content, which have the secondary effect of lowering the density of the fuel. This reduces the heating value by about another 1%.
Considerations for gasoline blending are driven primarily by the needs of the automobile engine, the requirements set forth by environmental regulations , and the refiners' economic concerns. In the United States, the 1990 Clean Air Act Amendment (CAAA) encompassed many regulations regarding gasoline, including mandates to reduce gasoline emissions of volatile organic compounds [ 17]. These objectives can be met by reducing RVPs and aromatic content and by adding oxygenated compounds. Reductions in RVP require lower amounts of 4-carbon and 5-carbon compounds in the finished product. Other requirements of the CAAA included strict controls on the permissible amount of benzene in gasoline (maximum 1%) and that there be a minimum amount of oxygen (2% by weight) blended into reformulated gasoline (RFG) [17 ]. In addition to these requirements and because of environmental and health reasons, gasoline blending must also take into account the production of various grades, or octane numbers, of fuel.
Iso-butane is a highly demanded chemical in the refinery industry for the production of alkylates (by alkylation with butenes), and methyl tert-butyl ether (MTBE) (from isobutene and methanol), both important additives for reformulated gasolines. n-Butane isomerization is performed over platinum supported on chlorinated alumina. The chlorine compound which is continuously supplied to the feed in order to maintain the activity [1] is harmful to the environment.
Biofuels have a wide range of properties regarding their impact on the environment and health. The two most common alcohols, methanol and ethanol, are good examples. Ethanol has little or no direct adverse effect; in fact, it is used in medical care and alcoholic beverages. The concern that being massively and cheaply produced for fuel it might encourage alcohol addiction, by direct use from the pump, in beverages, could be an issue. To avoid such a danger, when sold at the pump, ethanol is usually denatured, i.e., mixed with a small amount of gasoline that prevents human consumption. Moreover, ethanol is biodegradable and so leakage from tanks is of minor concern. On the other hand, methanol may be lethal if ingested and contaminates the water table if it leaks from storage tanks. It was used as an oxygenating additive for gasoline in the united states.
Twelve polycyclic aromatic hydrocarbons (PAHs) ranging from naphthalene to benzo (a)pyrene were also measured for both fuels. Gasoline showed a value of 206 mg/m 3, concentrated on naphthalene (116 mg/m 3) and fluoranthene (81 mg/m 3 ), the remainder being negligible or not detected. Ethanol did not produce detectable PAH emissions. Running with gasoline produced twice as much particulate matter as with ethanol.
Contemporary requirements imposed on the quality of petroleum products stipulated an increase in hydrogen consumption for hydrofining process from 0.3 to 1.8 wt. % of the quantity of crude oil consumed by refinery plants [1]. However, the reformulated gasoline program introduced in the USA in the 90s demands for a decline in reforming capacities, which considerably reduces the potential for hydrogen production at refinery plants [2]. The steam conversion of natural gas is a very power-intensive process affording a mixture of CO and H 2, which requires a subsequent separation of components for hydrogen to be utilized in hydroprocesses. The introduction of variable valence metals (nickel oxides) into cracking catalysts containing pentasil zeolites instead of Y-zeolites initiates methane partial oxidation reactions, the continuity of which is ensured by the catalytic cracking technology [3].
Reformulated gasoline is gasoline that has been blended in order to allow it to burn more cleanly and, therefore, emit fewer smog forming and toxic pollutants into the atmosphere .
A reformulated gasoline program was mandated by the US Congress in the 1990 Clean Air Act amendments. Since 1995, the program has been rolling out a reformulated gasoline option at gasoline stations across the United States.
The final RFG regulations, issued on December 15, 1993 (56 FR 7716), did not include procedures for opting out of the RFG program. EPA first adopted procedures that apply to opt-out petitions received through December 31, 1997 (Table 3). These interim procedures allowed States to opt-out 90 days after EPA approval of their petition.
States may implement their own cleaner burning gasoline programs without opting into the federal RFG program. For example, California requires participation of its northern counties in its State-wide reformulated gasoline program run by the California Air Resources Board (CARB) even though these areas are not part of the federal RFG program. Phoenix, Arizona (Maricopa County) opted out of the federal RFG but still requires that all gasoline meet either the federal or CARB reformulated gasoline specifications.