Manal Mohamed Matwally SOBIHA

Petroleum engineer

College of engineering

Cairo University

manalmfa@ hotmail.com

Background of the invention has behind over forty years of commercial experience and research. Although methanol has been widely

Methyl Tertiary Butyl Ether (MTBE) has been accepted manufactured for use in solvents and chemical production, worldwide as an octane booster and it is being blended it has also been successfully used for extending gasoline with gasoline up to 15 volume percent. The demand for supplies in many gasoline markets around the world. MTBE is growing rapidly and it is the fastest growing Unlike some other alcohols, methanol blending in gasoline chemical in use nowadays because it has replaced lead has been economical without government subsidies or fuel alkyl compounds in gasoline. The use of lead and other blending mandates.

metal containing compounds e.g., tetraethyl lead (TEL), Following the crude oil price shocks of the 1970's, tetramethyl lead (TML) and methyl-cyclo-pentadienyl methanol blends for use in the on road vehicle fleet began manganese tricarbonyl (MMT) as gasoline additives for extensive studies in the later 1970's and the 1980's. Based octane boosting is being discouraged. The emission of on this early research, methanol blends containing up to 15 their combustion products from vehicle exhausts creates percent by volume (Ml 5), were successfully operated by atmospheric pollution causing serious health hazards. automakers or oil companies in a number of large vehicle United States and some European countries have imposed fleet trials ( ~ 1000 vehicles each) in Sweden, Germany, a complete ban on the use of such compounds. New Zealand and China during that time.

Consequently, other blending agents are required to

increase the octane of gasoline in order to replace the metal

based agents presently in use in order. To have lead free Summary of the invention

high octane gasoline, one can use various components such

as methanol, tertiary butyl alcohol (TBA), secondary butyl The objective of the present invention is to provide a alcohol (SBA), tertiary amyl methyl ether (TAME) and gasoline blend of high octane number and ensuring methyl tertiary butyl ether (MTBE). Among these environmentally safe performance. The blend contains possibilities, MTBE appears to be an effective choice MTBE and methanol rather than MTBE only. because its physical, chemical, and thermal properties are According to the blending trials done, the obtained octane compatible with that of gasoline, especially in the boiling numbers of MTBE and methanol are very sensitive to the range where gasoline typically shows lowest antiknock composition and the octane numbers of the unleaded characteristics. gasoline. The octane number of MTBE and methanol blending generally rises-when base gasoline octane number

MTBE has exhibited the highest growth over the past decreases, MTBE and methanol concentration in the decade among all oxygenates being blended in gasoline as gasoline decreases or the saturate content of the gasoline octane improvers: world capacity of MTBE has increased increases. Further addition of MTBE and methanol approximately over ten-fold in this period and expected to increases the research octane number (RON) and motor increase further in the near future. Currently, MTBE world octane number (MON) of a gasoline.

production totals 12 million tons per year, with a

projection that this figure will increase to 20 million tons The effects of using both MTBE and methanol on the per year. This increased use of the MTBE is due to the antiknock properties of three types of base gasoline phasing out of lead from gasoline mandated by the samples of different octane numbers were determined. Environmental Protection Agency; EPA has permitted the MTBE and methanol in the concentration levels of 10 and addition of MTBE in the gasoline. 15 volume percent respectively were used. Increase in

RON and MON happened for all gasoline blends. The

Methanol is a clean burning, high octane blending gasoline samples having higher RON and MON were component for gasoline that is made from alternative non- found to have less increase in their octane numbers as petroleum energy sources such as natural gas, coal and compared to gasoline ¹ ^ with lower octane numbers. The biomass. Methanol with co-solvents has been sensitivity (RON-MON) was higher for gasoline having commercially blended into gasoline (petrol) at various higher- octane numbers. In addition to the effect of MTBE times and locations since the late 1970's; this technique and methanol on gasoline octane numbers, there are other properties that MTBE and methanol positively influenced. Most notable are the Reid vapor pressure (RVP) and distillation temperatures, used to control both hot and cold drivability performance. The RVP of MTBE-methanol- gasoline blend are within the specifications of gasoline.

Regulations regarding reduction in the use of lead in gasoline have had significant impact on the octane requirements of the gasoline pool. The use of MTBE and methanol has several advantages: increasing in octane number, improving engine efficiency in low speed acceleration, being soluble in hydrocarbons, being insensitive to lead level in the gasoline, improving tolerance to water; Other advantages for gasoline like toxicity, storage stability, no adverse health effects, no unusual problems in drivability, vapor lock tendency, fuel consumption, corrosion and fuel system material compatibility, reduction of catalytic reforming severity and reduction of carbon monoxide and hydrocarbon emissions. Also, on the operational level, this lend does not require additional precautions in the existing gasoline distribution system.

Detailed description of the invention

On volume basis, the final blend consists of 10% MTBE and 15% methanol. MTBE- methanol-gasoline blends show no phase separation in distribution systems in the presence of water. The tables show that there aren't any water separation even F adding water up to 0.7%

Test of water separation for gasoline blend at 10° and 35°