China
Africa
Explore chapters and articles related to this topic
Internal Combustion Engines
Published in Mehrdad Ehsani, Yimin Gao, Ali Emadi, and Fuel Cell Vehicles, 2017
Mehrdad Ehsani, Yimin Gao, Ali Emadi
The compression ratio of an engine is defined as the ratio of the total volume of a cylinder ( V2, as shown in Figure 3.3) to the volume when the piston moves to the TDC ( V1, as shown in Figure 3.3). Generally, a higher compression ratio yields high fuel conversion efficiency. The highest compression ratio of an SI engine is restricted by the octane number of the fuel. A high octane number allows higher compression ratio. For automotive gasoline SI engines, the compression ratio is in the range of 8–10.1 Some additives are usually added to gasoline to enhance its octane number. Typical additives are lead and tetraethyl lead, which are very effective in enhancing the octane number of gasoline and have been widely used. However, lead and tetraethyl lead are very poisonous and have been prohibited in most places in the world. Other gasoline additives include methyl tert-butyl ether (MTBE), tert-amyl methyl ether and ethyl tert-butyl ether. Alcohols, such as methanol and ethanol, are also used as gasoline additives to enhance the octane number of gasoline.
Petroleum Hydrocarbon Environmental Forensics and Remedial Site Investigation
Published in Rong Yue, Fundamentals of Environmental Site Assessment and Remediation, 2018
A modification of Environmental Protection Agency (EPA) Standard Method 8260B can be employed to support fingerprinting efforts in gasoline forensics investigations, age dating calculations, and evaluation of gasoline weathering. While the exact number of target analytes varies depending on the analytical laboratory, the method usually provides quantified data for 140–180 commonly identified volatile hydrocarbons. The analytes are representative of one of five gasoline compound classes: paraffins, isoparaffins, aromatics, naphthenes, and olefins (PIANO). Analysis of volatile gasoline range hydrocarbons is by purge-and-trap gas chromatography and mass spectrometry (GC/MS) operated in a full scan mode (Uhler et al. 2003; Stout et al. 2002; Douglas et al. 2007,2015). Additional target compounds can be added if desired. These include contemporary gasoline oxygenate compounds such as tert-butyl alcohol (tBA), MtBE, di-isopropyl ether (DIPE), ethyl tert-butyl ether (EtBE), and tert-amyl methyl ether (tAME). Other commonly identified compounds include the lead scavengers 1,2-dichloroethane and 1,2-dibromoethane, the gasoline additive methylcyclopentadienyl manganese tricarbonyl (MMT), and volatile sulfur-containing hydrocarbons. Target compound concentrations are normally calculated using external five-point calibration data and reported in micrograms per liter for water samples, micrograms per kilogram dry weight for soil, and milligrams per kilogram for separate phase product or NAPL samples. Chromatograms should be provided for all samples. Also, separate method blank (MB), duplicate (SD), lab control (LCS), and lab control duplicate (LCSD) samples in each processed batch should be prepared and analyzed for quality control purposes.
Catalytic Conversion Processes
Published in Marcio Wagner da Silva, Crude Oil Refining, 2023
Among the additives that were widely applied in the gasoline formulation, it’s possible to highlight oxygenated compounds as the ethers MTBE (tert-butyl ether), ETBE (ethyl tert-butyl ether), and TAME (tert-amyl methyl ether). These compounds, due to their physical and chemical characteristics, raise the gasoline octane number and, in shortage scenarios, can raise the available volume of this crude oil derivative.
Biodegradation of diisopropyl ether, ethyl tert-butyl ether, and other fuel oxygenates by Mycolicibacterium sp. strain CH28
Published in Bioremediation Journal, 2022
Ingrid Zsilinszky, Balázs Fehér, István Kiss, Attila Komóczi, Péter Gyula, Zsolt Szabó
Fuel oxygenates, such as methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), and diisopropyl ether (DIPE) have been increasingly used since the 1970s as octane enhancers to replace lead and induce complete fuel combustion. These chemicals are highly water-soluble with very low sorption capacity to soil particles, so they represent a major threat to aquatic wildlife and potable water supplies. Owing to their stable ether bonds and branched carbon structure they are usually poorly biodegradable in natural ecosystems (White, Russell, and Tidswell 1996; Squillace et al. 1997; Prince 2000) leading to long-term environmental pollutions. Moreover, some of them are classified as animal carcinogens (Hagiwara et al. 2015) or potential human carcinogens (Bogen and Heilman 2015; Romanelli and Evandri 2018), thus remediation of the growing number of polluted sites (Concawe 2012) has grown into an important issue.