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Methanol is the simplest saturated fatty alcohol. About 90% of methanol is used in the chemical industry as a raw material for producing formaldehyde, methyl tert-butyl ether (MTBE), acetic acid, methyl formate, chloromethane, methylamine, dimethylformamide, and other substances, while 10% is used in the energy industry. Among the basic organic chemical raw materials, methanol consumption is second only to ethylene, propylene, and benzene. There are currently over 120 types of products derived from the deep processing of methanol, while China has nearly 30 types of products that are processed directly from methanol as a raw material. 1-Methyltert-butyl ether MTBE is produced from methanol and isobutylene. It is produced in a fixed-bed reactor using an acidic catalyst (such as ion exchange resin). Isobutylene can also be replaced in the reaction by a fraction obtained from the steam cracking of crude gasoline after the removal of butadiene. 2 Formaldehyde: Formaldehyde is an important organic chemical raw material that is widely used in the production of polyoxymethylene resins, pentaerythritol, urethane, vinylon fibers, as well as in pharmaceuticals, **, pesticides, and dyes. In agriculture, it can be used to create urea-formaldehyde type slow-release fertilizers. The trend in formaldehyde consumption in our country is toward the forestry processing and chemical industries, which account for about 70% of the total consumption. The costs of producing acetic acid via the vinyl acetate method, acetylene method, and ethanol method are 1.2, 1.4, and 1.8 times respectively those of the methanol carboxylation method. 4 Methyl methacrylate is an organic glass material and a chemical intermediate with various applications, produced from methacrylic acid and methanol. In recent years, it has been widely used in the manufacture of optical fibers, optical discs, and lenses. 5 Methyl formate (and related compounds): A feasible route for producing methyl formate from methanol is: (1) Carboxylation of methanol in the liquid phase in the presence of sodium methoxide, followed by hydrolysis. This is a process that is widely used abroad; companies such as Leonard in the United States, Kemira in Finland, and the former Soviet Union all employ this method. (2) Methyl formate is produced by the dehydrogenation of methanol using copper-based catalysts; this process is already in industrial use abroad. The Southwest Chemical Research Institute in China has carried out technology transfer for this process, and a plant with an annual production capacity of 2,000 tons has now been put into operation. (3) A cobalt metal oxide catalyst is used for the vapor-phase oxidation of methanol to produce methyl formate; for example, methyl formate can be obtained using a V2O3–TiO2 catalyst, with a yield of 20 g/L·h, a ratio of HCOOCH2:CH2O of approximately 20, and an overall selectivity of over 90%. The advantages of this method are high selectivity, stable preparation properties, high yield, and the possibility of large-scale industrial production. Methyl formate can be used to produce formamide, formic acid, ONF, dimethyl methyl glycolate, methyl propanolate, and other substances, in addition to being used as a solvent and insecticide. 6 Methylamine compounds: Methylamine, dimethylamine, trimethylamine and other such compounds are intermediates used in the chemical industry, pharmaceuticals, pesticides, and coatings, and they hold considerable market potential. 7 Dimethyl ether: At normal temperature and pressure, dimethyl ether is a colorless and odorless gas. Due to its oxygen content and simple composition, it has excellent combustion properties and high efficiency; no residues or black smoke are produced during combustion, making it an excellent and clean fuel. Developing production technologies for dimethyl ether as a clean fuel has become a hot topic of research in the fields of energy, environment, and chemical engineering worldwide. The process of producing dimethyl ether from methanol dehydration is relatively simple, requires low investment, though the costs are somewhat high; it is suitable for medium and small-scale production. However, due to its strong dependence on methanol market prices, its cost is subject to uncertainty. In light of China’s national conditions, the Shanxi Coal Chemistry Institute of the Chinese Academy of Sciences proposed the use of dimethyl ether as a fuel for domestic use. This idea has been endorsed by scientists in countries such as the United States and Japan, and collaborative industrial trials on the production of dimethyl ether liquefied gas via methanol dehydration at a capacity of 500 tons per year have been carried out with Shaanxi New Fuel Appliance Company. This method is suitable for small nitrogen fertilizer plants that already have diol facilities, allowing them to use part or all of the methanol to produce dimethyl ether liquefied gas for domestic use. The design of an industrial pilot plant for the production of 10,000 t/a of dimethyl ether from methanol has been completed. With the further expansion of methanol production in numerous domestic plants, it is necessary to find new ways to utilize large quantities of methanol, and the conversion of methanol into dimethyl ether represents a potential application area for it. Dimethyl ether can be produced as a by-product of methanol synthesis, and the production ratio of methanol to dimethyl ether can be adjusted according to market conditions, which will yield good economic benefits. 8 Other chemical applications of methanol: Methanol is widely used in pesticides (such as trichlorfon, dichlorvos, dimethoate, etc.), pharmaceuticals, dyes, plastics, rubber, synthetic fibers, fertilizers, and other fields. This post was last edited by kaisl1314 on 2008-6-9 08:47.]